Code of Practice for Works on Public Streets

GENERAL

This Code is issued under Regulation 12 of the Street Works (Works on Public Streets) Regulations. It sets out the procedure to obtain permission to carry out works affecting public streets. It also stipulates the technical requirements, sets standards of materials and workmanship when carrying out utility services laying work, engineering works and any other works that affect the integrity of any public infrastructure. In the absence of any other technical/engineering requirements, the latest edition of the Authority’s Material and Workmanship Specifications shall prevail.

Nothing in this Code shall derogate or prejudice the Authority’s powers, rights and remedies under the Street Works Act and the Street Works (Works on Public Streets) Regulations, as amended from time to time.

Street Works Act

Street Works (Works on Public Streets) Regulations

Code of Practice for Traffic Control at Work Zone

This Code provides a useful guide on the posting and arrangement of temporary signs. It also contains illustrations on typical signing arrangement.

LTA’s Standard Details of Road Elements

The applicant is advised to consult the Authority on any requirements relating to works on public streets before making any formal application for approval.

Any preliminary consultation with the Authority or submission of plans shall not be taken as approval or disapproval of the proposed works or be construed as having the agreement of the Authority.

Unless otherwise stated, all conditions and comments as stipulated during the consultation process shall form part of the conditions for permit to carry out works affecting public streets.

The applicant shall re-submit the proposal for the comments of the Authority if the proposed works do not commence within 2 years from the date of comments given for the previous consultation.

All applications are to be submitted electronically through the Road Occupation Management Portal "Permit for (LTA.PROMPT)" at the following URL - https://prompt.lta.gov.sg.

For the purpose of this Code, the following definitions shall apply:

“applicant” means any person who makes or has made an application under Regulation 5 of the Regulations and includes a person whose application has been granted by the Authority;

“ASTM” means the American Society for Testing and Materials;

“Authority” means the Land Transport Authority of Singapore established under the Land Transport Authority of Singapore Act;

“BCA” means the Building and Construction Authority of Singapore;

“BS” means the current British Standards;

“Code of Practice” means the Code of Practice issued by the Authority under Regulation 12 of the Regulations and includes any amendment, which may be made to the Code of Practice from time to time;

“contractor” means a contractor who is registered with LTA under the LTA.PROMPT ;

“DIN” means the Deustches Institut fur Normung Standard

“emergency works” means works which must be carried out immediately in order to put end to or prevent the occurrence of any circumstances (whether existing or imminent or which the person requiring the works to be carried out believes on reasonable grounds to be existing or imminent) which are likely to cause serious danger to any person or property;

“LTA.PROMPT” means the Permit for Road Occupation Management Portal;

“major roads” means all roads other than minor roads;

“minor roads” means local access roads of carriageway width 7.4m or less;

“MPC” means the Master Plan Committee;

“no-opening period” means period during which no excavations are allowed on the road concerned. The no opening period is determined as follows:

“professional engineer” means a person who is registered as a civil or structural engineer under the Professional Engineers’ Act and who possesses a valid practising certificate issued under that Act;

“road lines” means any lines or other markings which are required by the Authority to be drawn on the surface of a public street for the guidance or direction of motorists or pedestrians using the public street;

“Regulations” means the Street Works (Works on Public Streets) Regulations as amended from time to time;

“site supervisor” means a person who possesses a Certificate in Pavement Construction and Maintenance Course or holds a degree in civil engineering or holds a recognized diploma in civil engineering with at least 5 years experience in road related works;

“SS” means the current Singapore Standards; and

“works” includes:

1. any construction work on a public street that is likely to affect the structural integrity and safe operation of any public street or road structure;

2. utility works within the meaning of Section 2 of the Street Works Act;

3. street works within the meaning of Section 2 of the Street Works Act;

4. any works for the purpose of construction or repairs of a building that require occupation of a public street or that affect the flow of traffic;

5. any works which are preparatory or incidental to any works referred to in paragraphs (a) to (d), such as the temporary storage or depositing of any building materials or debris or the placing of any equipment or the erection of any temporary structure, on the public street on which the works are to be or are being carried out.

This Code is divided into five main parts as follows:

1. Part I - Introduction

2. Part II - Submission Procedure & Requirements

3. Part III - Technical Requirements

   • Utility Works

   • Engineering Works

   • General Reinstatement

4. Part IV - Demerit Points System

This Code is divided into five main parts as follows:

1. Part I - Introduction

2. Part II - Submission Procedure & Requirements

3. Part III - Technical Requirements

   • Utility Works

   • Engineering Works

   • General Reinstatement

4. Part IV - Demerit Points System

Unless otherwise stated, references to a Regulation number (example, Regulation 12) in this Code are references to the regulations numbered in the Street Works (Works on Public Streets) Regulations, as amended from time to time.

Unless otherwise stated, references to a Regulation number (example, Regulation 12) in this Code are references to the regulations numbered in the Street Works (Works on Public Streets) Regulations, as amended from time to time.

The submission procedures and requirements for obtaining approval for permit to carry out works affecting public streets are stipulated in Part II of this Code.

The submission procedures and requirements for obtaining approval for permit to carry out works affecting public streets are stipulated in Part II of this Code.

The technical requirements for the various types of utility services laying, engineering works and related reinstatement works are set out in Part III of this Code.

The technical requirements for the various types of utility services laying, engineering works and related reinstatement works are set out in Part III of this Code.

Part IV of this Code stipulates the circumstances under which a contractor will be issued with demerit points and/or fined. It also sets out the criteria by which a contractor can be suspended.

Part IV of this Code stipulates the circumstances under which a contractor will be issued with demerit points and/or fined. It also sets out the criteria by which a contractor can be suspended.

WORKS PROPOSAL ON PUBLIC STREETS

This section stipulates the procedures and requirements for obtaining in-principle pre-consultation approval for work proposals that affect public streets and/or road infrastructure before submission of application for permit to commence work.

Eight sets of plans for the following work proposals shall be submitted to the Authority for in-principle pre-consultation approval:

1. Work proposal that requires Master Plan Committee (MPC) adoption;

2. Any improvement or upgrading schemes for utility services;

3. Any excavation works of 4m depth or deeper; and

4. Tunnelling works and engineering works.

The submission should include but not be limited to the following:

1. Proposed extent of works including route alignment and excavation area in relation to public streets;

2. Preliminary impact analysis of the works on public streets or road infrastructure/s;

3. Proposed feasible method of work execution i.e. open-cut, pipe-jacking, etc.; and

4. Letters of clearance from other relevant authorities.

This section stipulates the procedures and requirements for obtaining approval for permit to commence and carry out works that affects the public streets and/or road infrastructure. (Please see Appendix B for the submission process).

Applications for permit to commence and carry out works must be submitted electronically through the “Permit for Road Occupation Management Portal (LTA.PROMPT)” at this URL- https://prompt.lta.gov.sg.

Applicants, who meet the criteria under Regulation 5 of the Regulations, must register online as an applicant with the LTA.PROMPT before they are allowed to make any submissions for permission to carry out works.

An application has to be submitted to the Authority for permission to carry out works on public streets after the necessary pre-consultation approvals have been obtained from the relevant authorities or agencies. The types of works shall be as defined in Section 1.5 (Definitions) of this Code. Examples of these works shall include but not be limited to the following:

1. excavation to lay or repair utility services;

2. soil investigation works;

3. parking of a vehicular crane on the road for the purpose of construction or repairs of a building;

4. external works of developments.

The electronic application shall be accompanied by the soft copy of the following items:

1. Location and site plans of the proposed works to be carried out on the public streets;

2. Pre-condition photographic survey report, including but not limited to, current site photographs (with date and time stamped) of existing roads and related street furniture (including road markings), within the influence zone of work location and etc.;

3. Method statement of works to be carried out;

4. Photographs and schematic diagrams of the extent of the existing road markings where applicable;

5. Notification of emergency openings, where applicable;

6. Engineering evaluation report accompanied by plan for engineering works, where applicable;

7. Certified topographic survey plans that indicate the scale, boundary lines, lot numbers and existing surrounding roads and road structures, etc (only applicable for critical engineering works involving tunnelling, piled foundation, basement construction, etc that are likely to affect the structural integrity of the public streets); and

8. A copy of the Public Liability Policy Schedule/Endorsement(s) for a limit of not less than S$1million (any one accident and unlimited during any one period). The policy shall provide for the Authority's interests to be noted as "Principal". The Public Liability policy shall also include a "cross liability" clause. The policy shall indemnify the Authority against any liability, in respect of personal injury/injuries or damage to property/properties and existing services, caused as a result of the execution of the works. The period shall cover the works duration and defects liability period. All documents, including all endorsements shall be officially signed and stamped by the insurance company.

9. Letters of development / planning clearances, where applicable.

The Authority may also require a Banker’s Guarantee, of an appropriate amount to be determined by the Authority, to be submitted if it deems fit. (Please see sample formats as shown in Appendix C & D).

Applicants are advised to visit the LTA.PROMPT website for more information on the electronic application and the recommended formats of the attachments.

For works with no traffic lane reduction, the permit will be revoked if no works are commenced within 28 days (herein referred to as the “validity period”) from the date approved by the Authority for the commencement of the works.

For works involving traffic lane reduction, the applicant shall ensure the affected roads are fully reinstated by the approved permit completion date.

Upon completion of the works, the applicant must notify the Authority of the actual completion date through LTA.PROMPT within 7 days. The applicant shall also submit in the same notification a post condition photographic survey report which contains relevant site photos (with date and time stamp) of reinstated works and the surrounding roads, including lane markings.

If the works cannot be completed by the approved permit completion date, the applicant must submit for extension of time through LTA.PROMPT, before the approved permit completion date.

Otherwise, any works beyond the approved permit completion date shall be considered as unauthorized works.

For works involving traffic lane reduction, if the applicant is unable to complete the works by the approved extended completion date, the applicant may submit a new application to continue with the remaining works subject to the road affected by the earlier work being fully resurfaced at the end of the approved extended completion date.

The applicant is required to submit the reinstatement test report where excavation and/or engineering work are involved, through the LTA.PROMPT to the Authority, as and when required by the Authority. The Defects Liability Period or DLP to be imposed will be determined by the Authority depending on the type of works and depth of excavation. There will be no DLP imposed for works that involve lane closure only e.g. parking of mobile crane to carry out hoisting work, etc.

Upon expiry of the DLP, the applicant shall apply for the handing-over of the reinstatement works to the Authority through the LTA.PROMPT.

The applicant shall ensure the works, for which a permit has been granted by the Authority are according to the statutory and technical requirements, guidelines and Codes of Practice for all relevant authorities and agencies and any other conditions as specified by the Authority.

The applicant shall also ensure that appropriate traffic control plans, according to the Code of Practice for Traffic Control, are implemented on site. He shall also ensure that appropriate information signs informing road users of impending works are posted strategically on site at least 1 week in advance of the commencement of works. The signs shall contain information such as the type of works, agency responsible for the works, the start and end dates of the works and the contact numbers for enquiries.

Applicant has to notify the Authority if there is a change in applicant, contractor and/or supervisor.

Applicant shall provide daily update of road works, which involves lane/road closures, to LTA via LTA.PROMPT system upon commencement and cessation of the works.

In the event of an emergency works, the applicant must inform the Authority immediately through telephone to LTA CALL CENTRE (1800-CALL-LTA) and follow up with official notification via email or facsimile within 3 working days of the emergency opening duly endorsed by an authorized officer. The application must be submitted through the LTA.PROMPT Portal within 7 working days.

Barring the Authority’s approval, the applicant shall fulfil the statutory requirements of other relevant authorities before commencement of works on public streets. The applicant shall also liaise and co-ordinate with all other relevant agencies or persons whose operations or utilities may be affected by the carrying out of the works.

Where the works are carried out for a building development, the applicant shall liaise closely with the Qualified Person of the development to ensure that all works on public streets including utility services connections are arranged such that they can be completed with minimum inconvenience to the public. The permanent reinstatement works shall be carried out after all the necessary works and utility services connections are completed or deem necessary by the Authority.

Where scheduled bus routes are affected by the works, the applicant shall liaise with the relevant bus operators to ensure minimum disruption to the bus services.

The applicant shall make himself/herself readily contactable at the contact information given in the application, any time of the day during the duration of the actual work.

In accordance with Regulation 14, the person for whom the works to be carried out shall appoint a suitably qualified site supervisor to supervise the carrying out of works

He shall be responsible for the overall site safety and site management and provide full-time supervision on site to supervise the works and receive directions from the Authority where necessary.

The site supervisor shall also ensure that the appropriate traffic control plan is being implemented on site.

Without prejudice to Regulations 14, 15 and 18, the contractor shall be responsible for the safe execution of the works in strict compliance with the requirements as stipulated in this Code and the permit issued by the Authority.

The contractor shall ensure that appropriate traffic control plans are implemented on site.

The contractor appointed by the applicant to carry out any works on any public street shall be registered with the Building and Construction Authority. Please refer to Appendix F on the approved categories of registered contractors for works on public streets.

The Authority may consider other categories of registered contractors to perform works on public streets that do not involve opening up of the public streets. Examples of such works are lane closure for lifting, hoisting activities and maintenance of building facade (i.e painting or washing).

The Defects Liability Period (DLP) is a warranty period that starts after the completion of a satisfactory permanent reinstatement. The applicant shall ensure that the reinstatement work is maintained in a defect-free condition during the DLP. The applicant shall monitor the condition of the reinstatement work and any defect which appears during the DLP shall be promptly rectified.

The DLP shall only begin when the Authority is satisfied with the permanent reinstatement. The DLP shall run for:

1. 1 year for works where the depth of excavation is 1.5m or less; and

2. 2 years for works where the depth of excavation is more than 1.5m.

This section stipulates the additional procedures and requirements for obtaining in-principle planning approval to commence engineering works within the public streets.

Engineering works refer to any construction work that is likely to affect the structural integrity and safe operation of any public streets or road structure.

The applicant or the appointed professional engineer is encouraged to initiate a consultation meeting with the Authority to discuss his proposal before submitting the engineering work proposal to the Authority.

Upon clearance of engineering work proposal, the applicant or the appointed professional engineer shall submit an application for permit to carry out the engineering works through the “Permit for Road (LTA.PROMPT).

The requirements given in the written directions of the engineering works proposal shall form part of the conditions for the permit to carry out the engineering works.

No engineering work shall commence on site without the approval by the Authority issued through the LTA.PROMPT.

The Authority may impose any other requirements deemed necessary for safeguarding of the public streets and road structures.

An application for engineering works proposal shall be submitted by the applicant or the appointed professional engineer and accompanied by the following items:

1. Plan for engineering works;

2. Engineering evaluation report;

3. Instrumentation proposal;

4. Method statement of work;

5. Contingency plans & Emergency procedure;

6. Pre-condition survey report;

7. Construction schedule;

8. Traffic control plan, where applicable; and

9. Relevant documents indicating planning approval from the competent authority.

The requirements for the above items are given in Clause 5.3 to Clause 5.11 of this section for compliance.

Plan for engineering works shall be prepared and endorsed by a professional engineer.

Layout plans and cross sectional details shall indicate the following items:

1. Scale of the plans;

2. Location plan of proposed engineering works; and

3. Vertical and horizontal distances of the engineering works (site preparation, substructures and building construction works, etc.) in relation to the existing road reserve line and/ or road structure, where applicable.

Engineering evaluation report shall be prepared and endorsed by the appointed professional engineer. The engineering report shall also be accompanied by the checklist for temporary earth retaining structure (Please see sample format of the checklist as shown in Appendix E).

The above report shall address the following items:

1. Predicted movements of the existing road and/ or road structures due to the proposed engineering works at various stages of construction and at completion of the works. The evaluation shall include the following items:

   1. Detailed examination of the ground conditions at site;

   2. Calculations for the derivations of the predicted movements; and

   3. Appropriate sensitivity analysis to check that the assessment would not be affected by any variation in input parameters and conditions that may occur during all stages of the construction work.

2. Assessment of the likely effects of movement on the existing road structure, where applicable.

3. Proposal for any special measures or advance works needed to minimise the susceptibility of the existing road and/ or road structure to damage and to ensure the safe operation of the public street.

The Authority may specify any other requirement on the engineering evaluation report which are deemed necessary for the safeguarding of the public streets and road structures.

Instrumentation proposal shall be prepared and endorsed by the appointed professional engineer.

The proposal shall include the following items:

1. Comprehensive monitoring system to monitor the movement of the existing road and/ or road structure and the ground adjacent to it;

2. Layout plans and relevant cross-sections indicating the locations of proposed instruments relative to the road and/ or road structures;

3. Details of the instruments or equipment, including the types, function of instruments, depth of installation, etc.;

4. Frequency of monitoring;

5. Review levels, i.e. trigger, design and allowable for all instruments; and

6. Valid calibration certificates for the instruments proposed, where applicable.

A copy of the initial readings endorsed by the appointed professional engineer shall be submitted to the Authority before the commencement of works.

Method statement for carrying out any engineering works shall be prepared and endorsed by the appointed professional engineer.

The proposal shall be accompanied by the following items:

1. Location plan showing the boundary line of the engineering works relative to the road and/ or road structures;

2. Site layout plan showing the site set-out, movement of machineries and storage of plant & equipment;

3. Write-up and/or plans indicating step-by-step sequence of carrying out each phase of works or activities; and

4. Construction risk analysis to identify potential risk of construction activities on road users and public streets. Both the general construction hazards and geotechnical risks shall be presented with the corresponding risks assessed and precautionary measures to mitigate these risks.

A contingency plan and emergency procedure prepared using the guidelines given in Section 5.8 below shall be endorsed and submitted by the appointed professional engineer.

The contingency plan shall include immediate rectification, temporary traffic diversion/ control plans in the event that roads and/ or road structures are affected due to excessive ground movements.

The emergency procedure shall include the project organisation chart and a list of emergency contact numbers. The reporting procedure for incident and roles of key personnel must be clearly defined.

This section serves as a guide to the preparation of a contingency plan and emergency procedure. It aims to ensure that a set of the contingency plan and emergency procedure is in place for immediate implementation should the need arise at site.

An emergency situation may arise due to various incidents at site, such as:

1. Monitoring results exceed the alert levels / work suspension levels specified by the qualified person;

2. Accidents such as construction material falling onto the public street, crane toppling onto the road structure; and

3. Failure/ collapse of temporary earth retaining structure that affects the structural integrity and/ or safe operation of the public street, etc.

The appointed professional engineer shall prepare an emergency plan stating the immediate actions to be taken in the event of an emergency in order to safeguard the integrity of the public street. In addition, the follow-up actions to be taken after the implementation of control measures at site should also be provided.

The appointed professional engineer shall also identify all possible hazardous situations that may arise due to the proposed works and prepare a contingency plan.

An emergency procedure report shall include the following items:

1. Descriptions of the project and proposed works or activities to be carried out;

2. List of possible hazard/ emergency situations that may arise due to the proposed works or activities;

3. Governing criteria for initiating an emergency procedure;

4. Step-by-step procedure or flow chart showing the actions to be taken by the appointed professional engineer and the project team should an emergency happen. Where applicable, the procedure shall incorporate the steps to review the monitoring results obtained, the re-examination of the method of work, the revision to the predictions, the review of instrumentation provisions, the contingency measures to be implemented, etc.; and

5. Call-up list stating the names and contact numbers of all key personnel including the qualified person, the project manager, the site supervisors, and the instrumentation specialist. A flow chart for the emergency reporting shall also be included.

Condition surveys to be undertaken by a professional engineer or building surveyor shall include physical surveys of road and road structures that comprise existing footpath and drains within the influence zone of engineering works to be carried out.

A topographical survey for road reduced levels, at 3m grid spacing along each traffic lane shall be conducted and certified by licensed land surveyor.

A pre-condition survey report that comprises of both condition and topographical survey of engineering works shall be prepared and endorsed by an independent person who has the appropriate qualifications, for example, professional engineer or building surveyor.

A copy of the endorsed condition survey report shall be submitted to the Authority before commencement of work.

A comprehensive work programme/ schedule shall be submitted. The programme may be in the form of bar/ Gantt charts that indicate the sequence of works and the duration required.

For all works within the public streets, the requirements, specifications and arrangements of the traffic control plans (TCP) shall be in accordance with the LTA’s Code of Practice for Traffic Control at Work Zone.

The applicant shall inform the Authority in writing of the appointed professional engineer or the professional engineer’s assignee to provide full-time supervision on site for the engineering works.

The applicant shall notify the Authority in writing whenever there is a change in the professional engineer / professional engineer’s assignee appointed for supervision.

The Authority will issue a letter of clearance in writing to the applicant upon approving the relevant engineering work proposal.

Once the letter of clearance is obtained, the applicant shall submit an application through the “Permit for Road Occupation Management Portal (LTA.PROMPT)” for the permit to commence and carry out works on public streets.

In accordance with Regulation 21, amendment plan shall be submitted to the Authority for approval if any engineering works depart or deviate from the approved plan.

An application for approval of amendment plans shall be accompanied by one set of the following documents prepared, signed and submitted by the qualified person:

1. A copy of the amendment plans showing the amended proposal; and

2. Engineering evaluation report accompanied by plans for engineering works, if applicable.

No person shall carry out any engineering works in departure or deviation from the approved plan unless the amendment plan has been approved.

UTILITY WORKS

This section stipulates the technical requirements, sets standards of quality of materials and workmanship when carrying out utility works within the public streets.

“Restricted area” refers to any public street where no breaking up or opening up of a street is allowed. The objective of the restriction is to enhance road safety and reduce inconvenience to road users.

There shall be no openings or works allowed on “restricted areas”. These areas include:

1. Road reserves of expressway;

2. Carriageways with ‘specially treated’ areas such as rigid pavement, semi-rigid pavement, enhanced school zone, street print, etc.;

3. Bridges and underpasses; and

4. Roads which are under “no-opening period”.

Trial holes are usually dug up to detect existing utilities and determine the available space for new utility.

A maximum of only two (2) trial holes sre permitted to be opened up at any one time on carriageway along the same road.

All trial holes shall be properly backfilled and affected road surface shall be reinstated to the Authority’s requirements.

All utilities shall be laid at a minimum depth as prescribed in Table 6.1 below. The minimum depth of utility laid below the public streets shall be measured from the road surface/ sidetable to the top of utilities pipes/cables.

Table 6.1 Minimum depth requirements for laying of utility

Utility owner may consider the alternative depth requirements for fibre optic cables (FOC) laying only, subject to compliance with the following conditions:

1. Telecommunication companies (Telcos) /cable owners to look into necessary safeguarding measures and identification markers to protect their cables from damage.

2. No one after taking reasonable precautions should be held liable for damaging cables laid at shallow depth.

3. Telcos/ Cable owners to bear diversion costs when their cables laid at revised shallow depth are affected by public infrastructure works.

4. Telcos/Cable owners to ensure that their cable route meets the statutory requirements of other utility agencies/service providers e.g. no new services are currently allowed to be laid over other existing services.

All utilities laid shall have a lateral clearance from the rigid pavement. The minimum lateral clearance is 2.0 metre or the depth of the utilities, whichever is greater, from the edge of rigid pavement.

Utility owner shall seek planning approval from LTA Road Works Regulation & Licensing Division (RWRL) for laying of services over / under-crossing culverts and other road structures.

All utilities laid shall also comply with the statutory requirements of other utility owners.

There shall not be any new manholes, inspection chambers or valves constructed on road or on ramps of footpath and cycling track.

There shall not be any new Over-Ground (OG) boxes, fire hydrants or any other apparatus erected on footpath and cycling track.

OG boxes shall be located with lateral clearance of at least 2m away from the kerb line along the major road, so as to allow adequate sight distance for drivers exiting the minor road.

In the event that the requirement in 6.5.3 cannot be achieved due to site constraints, OG Boxes shall be located with lateral clearance of at least 0.6m away from the kerb line with the minimum offset distance from the minor road as summarized in Table 6.2, depending on the design speed of major road. Please refer to Figure 6.1 – Illustration to locate OG Box.

Notes:

¹ Desirable (m) – In-line with Intersection Sight Distance values in LTA Design Criteria

² Absolute Minimum (m) – In-line with Stopping Sight Distance values in LTA Design Criteria

The placement of OG Boxes should meet the desirable offset distance from the minor road. Absolute minimum offset distance may be considered if there are valid reasons, e.g. site constraints such as short length of sidetable between road intersections, presence of existing objects or objection from 3rd party, etc.

The Authority may consider waiver of the requirements in this sub-section on a case by case basis. The applicant is required to submit valid reasons in writing to the Authority for consideration. If the waiver is given, the applicant shall ensure that

• the apparatus shall not be placed on the carriageway in a way that will affect the riding quality of the road e.g. manholes shall not be constructed in a cluster or along the wheel path of vehicles;

• the apparatus shall not be placed on the footpath in a way that will obstruct road-related facilities or endanger road users. The minimum passable width of 1.5m along the footpath must be maintained;

• the owner shall be responsible for maintaining the apparatus so as to ensure the safety of the road users and the riding quality of the road; and

• the owner shall bear the cost of raising, lowering or relocating the apparatus as and when required by the Authority.

The applicant shall seek concurrent approval from relevant authorities for erection of new Over-Ground (OG) boxes, fire hydrants or any other apparatus at back lane and service road.

The applicant shall take measures to protect all road carriageways, road structures, apparatus and road-related facilities during the course of work on public streets. Any damages caused by the work shall be reinstated immediately.

For works above road structures, excavation by mechanical means shall not be allowed within 500 millimeters from the top of the structure.

Road structures includes the followings:

1. Vehicular flyovers, viaducts and bridges;

2. Box-culverts;

3. Road tunnels and underpasses;

4. Pedestrian overhead bridges; and

5. Pedestrian underpasses.

   The applicant shall propose a system to monitor the integrity of all road structures and to detect any damages or defects to these road structures. The applicant shall submit regular monitoring reports to the Authority once the system is approved. Notwithstanding the regular reports, the applicant shall inform the Authority immediately of any defects that appear in the course of work.

Road related facilities include traffic signs, traffic lights, railings, traffic light controllers and poles, street light posts, etc. The applicant shall ensure that these facilities are not damaged, moved, removed, or being obstructed as a result of the work.

All temporary earth retaining structures (TERS) for excavation works must be structurally safe and robust. For excavation exceeding 1.5m deep, the applicant shall ensure that the TERS is designed and endorsed by a professional engineer. The professional engineer and contractors shall take adequate precautions & considerations to ensure the safety of the public and the workers, and to protect the adjoining road carriageways and road structures in his design and construction of the TERS. The technical requirements for TERS are set out in Section 7 of this Code.

All construction materials used for the temporary earth retaining system such as sheetpiles, walers and struts shall be removed completely upon completion of the works.

The requirements, specifications and arrangements for temporary traffic control shall be in accordance with the latest edition of LTA’s Code of Practice for Traffic Control at Work Zone.

The applicant/ contractor shall seek clearance from LTA’s Intelligent Transport Systems Operations Divison (ITS Operations) before commencing works on major arterial roads and/ or near traffic junctions.

For contractors who need to carry out works on public streets, the occupation of carriageway for these works shall be restricted to only one (1) traffic lane width at any one time.

The roads (including slip roads) are not allowed to be closed completely at any time for any works.

Traffic lane shall not be occupied during the peak hours; the applicant is required to use construction methods such as covering trenches with steel decking, pipe jacking and tunnelling to avoid the occupation of the lanes. Otherwise, the Authority may require the applicant to temporarily provide an alternative to replace the affected traffic lane.

Traffic lane shall not be occupied such that it affects traffic in two or more directions e.g. traffic junctions.

The Authority may consider waiver of the requirements in this sub-section on a case by case basis. The applicant is required to submit valid reasons in writing to the Authority for consideration. The submission should include a study on the proposed utility works with traffic impact assessment of the affected road and the proposed traffic control plan. The submission shall be duly endorsed by a traffic consultant.

For maintenance of greenery on expressway, temporary lane occupation shall be limited to a maximum distance of 300m or before next slip road entry of expressway, whichever is shorter. The applicant shall submit a notification to LTA’s Intelligent Transport Systems Operation Division (ITS Operations) via the LTA. PROMPT prior to commencing works.

Lane occupation for works on public streets is not permissible during the traffic peak hours, which may vary depending on the traffic condition.

Traffic peak hours are generally as follows:

A listing of roads with different traffic peak hours is available on LTA.PROMPT system via URL – https://prompt.lta.gov.sg and will be updated from time to time.

Occupation of bus-lane for works shall not be allowed during the bus-lane operation hours.

The applicant shall obtain permission from National Environment Agency (NEA) and to notify all the affected stakeholders including residents, hotels, grassroot organizations, etc before the commencement of works.

The applicant shall also notify NEA-Call Centre and LTA-Call Centre if the work has to be carried out from 7pm to 7am on weekdays or the entire day on weekends and public holidays.

There shall be no noisy night work allowed in residential areas, hotels, hospitals, etc.

Notwithstanding the Peak Hours requirement, the affected traffic lane shall be restored and re-opened timely to traffic if the continuation of work is likely to cause traffic to pile up and the road to reach its optimal level of service.

The contractor shall provide adequate standby materials, equipment and necessary resources to effect remedial action and re-open the affected traffic lane when any of the following situations is observed:

1. traffic tailback of more than 200m; or

2. motorists take 3 or more traffic cycle to clear traffic junction.

The contractor shall plan and limit the extent of excavation work according to the availability of his resources such that the affected traffic lane can be re-opened to traffic should the need arises.

Steel decking shall be used to cover trenches on public streets to allow traffic flow while works are being carried out beneath. The decking shall be laid flush with the road level, all joints between steel decking panels shall be firmly fixed by welding or by other appropriate means, with no gap between steel decking panels, adjacent road surface and road kerb, all affected road markings reinstated over steel decking and to ensure proper installation to avoid noise generation.

The applicant shall submit the following items prior to opening of the completed temporary decking for traffic use:

1. design calculations and construction drawings, duly endorsed by the professional engineer; and

2. a letter certified by the professional engineer on his inspection of the Temporary Steel Decking System as constructed fully in accordance with his design calculations and details. This certificate shall be submitted within 3 days of completion of the temporary decking and prior to opening for traffic use.

3. Letter of clearance from BCA on the temporary steel decking system.

The professional engineer shall ensure that the steel decking is designed to relevant code and standard to carry the traffic loading, and to maintain a skid resistance value of not less than 65 (BPN) as per BS EN 13036-4, at all times.

Before installation of new decking, physical testing shall be carried out on two deck panels or 5% of the total number of deck panels, whichever is greater, to demonstrate that the required skid resistance value is complied with. All testing shall be carried out using the Portable Skid Resistance Tester and according to the operating procedure defined in standard BS EN 13036-4.

Upon deploying temporary steel decking system onsite, the applicant/ contractor shall conduct weekly visual inspection of the steel decking in the presence of the professional engineer or his/her representative. Inspection report shall include:

1. Photographs and descriptive appraisal of temporary decking physical condition (e.g. report any defects/damages).

2. Surface conditions – to maintain a minimum skid resistance value of 65 BPN as per BS EN 13036-4 and road markings, where affected.

3. Condition of the structural integrity

4. Remedial actions taken (if any)

The inspection report shall be submitted to the Authority as and when required by the Authority.

The applicant shall apply and obtain clearance of the Authority's Development and Building Control Division (Rail Section) to carry out the restricted activities describe in the Rapid Transit Systems (Railway Protection, Restricted Activities) Regulations and any subsequent amendments within the Railway Protection Zone and Railway Safety Zone.

The applicant shall comply with the Authority's latest Code of Practice for Railway Protection in carrying out these works and services laying within the Railway Protection Zone. The Applicant may refer to the 'Guide to Carrying out Restricted Activities within Railway Protection and Safety Zones' published by the Authority for guidance.

The cleanliness of the public streets within the vicinity of temporary road access and work site, shall be supervised and maintained during the entire duration of works.

Immediate remedial actions must be taken to clear any spillage onto the surrounding public streets resulting from the works, failing which the Authority may clear the spillage and recover all cost incurred from the applicant.

There shall not be any parking of vehicles or deposition of debris, building materials, skip, etc. on the public streets including sidetable and footpath.

At locations where the footpath is affected, a safe alternative temporary footpath of equivalent standard to the permanent footpath shall be provided for pedestrians at all times.

Any damages to the footpaths, road pavement, lane markings and other road furniture caused by the works shall be made good immediately.

This section stipulates the technical requirements for compliance at the design and construction stages of engineering works being carried out on public street.

This Section shall be read in conjunction with Section 6 of the Code with respect to the requirements/ conditions for occupation of carriageway.

Engineering works refer to construction works that are likely to affect the structural integrity and safe operation of any public streets.

The Authority reserves the right to impose any additional requirements deemed necessary to safeguard the road infrastructures.

The applicant and/ or the appointed professional engineer shall also ensure full compliance with the relevant regulations e.g. Building Control Act, Rapid Transit System (RTS) Act and Regulation, etc.

All TERS shall be designed and executed to minimize ground movements.

The design of temporary and permanent Works shall comply with LTA’s traffic loading as stipulated in the Civil Design Criteria Chapter 3.

All TERS designs shall be carried out and endorsed by a professional engineer.

All TERS works which fall within the public street shall be designed for removal upon completion of works.

TERS shall be designed such that there is no risk of damage to the adjoining road and road structures during removal.

All voids left in the ground due to the extraction of TERS shall be immediately filled with grout. The grout mix and method of grouting shall be proposed and endorsed by the appointed professional engineer.

The ground shall be monitored for changes in ground conditions and movements which may result from the proposed works.

Typical ground instruments such as water standpipes, inclinometers, piezometers, borehole extensometers and settlement markers shall be provided where applicable.

The type of ground instrument to be provided shall be appropriate for the ground conditions.

Ground settlement points shall be installed such that the movement of the ground can be measured. Where points have to be installed on road carriageway, then the ground settlement points shall be anchored into the ground below the road pavement. Sleeves shall be provided through the road pavement so that the measured settlement is not affected by the presence of the road pavement. A grid of surface points to monitor heave or settlement shall be established with spacing between points in both directions shall not be more than 5m.

The monitoring shall extend along the full length of the work, and cover the zone of influence for excavation work and engineering works.

Adequate monitoring instruments shall be provided. The spacing of instruments shall be such that adverse changes in the ground conditions can be captured. The frequency of monitoring must tie-in with the criticality of the stage of works. Instrumentation proposal shall be submitted to the Authority for approval.

Before termination of monitoring, the engineering works must be completed, the ground conditions and monitoring readings both shown to have stabilized and thereafter no further change is expected in the long term.

Upon cessation of monitoring works, all instruments installed within public streets shall be removed and the ground and any affected road and road structure shall be made good to the acceptance of the Authority.

Intervention value defines the maximum severity of a defect at or before which remedial action must be taken.

The intervention values for movements of road carriageway are as follows:

Preventive measures shall be taken during construction stage of engineering work to prevent any damage to the existing road and road structures.

The appointed professional engineer shall be responsible to:

1. ensure that the works comply with the construction method statements and good engineering practice;

2. monitor compliance of criteria;

3. ensure that contingency measures are implemented in a timely manner; and

4. take any other necessary measures to ensure that at no time shall the work being carried out pose any danger to the safety of the public.

The professional engineer shall exercise due diligence and reasonable care in monitoring the effects of engineering works on the road and road structures. He shall analyse the monitoring results, predict the likely trends and notify the Authority of any deviation from the predicted results and trends. He shall also make proposal to change the method of working or to implement contingency measures as a result of monitoring.

Once the monitoring readings are taken, they shall be submitted to the Authority as required. A report of the review of the monitoring results endorsed by the professional engineer shall be submitted to the Authority within a week from the date of monitoring.

All monitoring results shall be analysed and compared with the alert and work suspension levels specified by the professional engineer. The report shall also include description on progress of works and conditions of road infrastructures.

During the progress of the works, should it become apparent from the monitoring results that the ground movement and/or the structural movement are likely to exceed the limits; the Authority may revoke the permit. The constructor shall take immediate measures to control movements within the acceptable limits, all at the cost and expense of the contractor. The work will only be allowed to resume if it can be demonstrated that the continuity of works will not adversely affect the public street and/ or road structure.

During the progress of the works, should it become apparent from the monitoring results that the ground movement and/or the structural movement are likely to exceed the limits; the Authority may revoke the permit. The constructor shall take immediate measures to control movements within the acceptable limits, all at the cost and expense of the contractor. The work will only be allowed to resume if it can be demonstrated that the continuity of works will not adversely affect the public street and/ or road structure.

In the event of an incident relating to the works, the applicant shall notify LTA Call Centre (1800-2255582) and LTA RARL Division immediately. The interim incident report must reach LTA RARL within the next 12 hours. The detailed incident report must be submitted within the next 7 working days. (Incident report)

Condition surveys of the public streets shall be carried out upon completion of the proposed works or at intermediate stages as directed by the Authority. Defects found shall be highlighted and compared with the findings of precondition survey.

A proposal on making good of all defects arising from the work found in the public streets prepared and endorsed by the professional engineer shall be submitted to the Authority for prior approval.

Making good of defects arising from the work shall be completed to the satisfaction of the Authority. The contractor shall bear all direct or indirect costs arising from the rectification works. A report on the remedial work done shall be submitted upon completion of all remedial work.

Defects and damages rectified shall be highlighted with photograph and compared with those found after the completion of work indicated in the final condition survey report.

The general technical requirements as in section 6.7, 6.8, 6.9, 6.10, 6.11, 6.12 and 6.13 of the Code shall be complied with for carrying out engineering works on public streets.

The Applicant shall carry out the reinstatement of the affected public streets upon completion of works according to the current practices, requirements and standards of the Authority. The existing condition of the public streets may not be taken as the standards of the Authority.

For road pavement, the reinstated work shall comply with the permitted materials and layer thickness as specified in Figure 8.1 – Pavement Reinstatement Details.

The reinstatements of public streets with the use of unsuitable materials, insufficient depth of backfilling, improper compaction and settlement or cave in of public streets arising from works are not acceptable. These defective reinstatements shall be rectified to the requirement of Authority at the expense of the applicant. Section 9 of Part III lists the characteristics and requirements for the reinstatement of public streets.

The edges shall be neatly cut with straight edge and the finished level flush with the existing road surface even if the surface is to be resurfaced for permanent reinstatement later on. Depending on site condition, the Authority may allow the finished level of the interim reinstatement with tolerance of not more than 5mm higher than the surrounding road surface – see Appendix G for illustation.

Surfacing works by methods such as milling-and-patching or hot in-place resurfacing for the permanent reinstatement shall complete by the approved permit completion date, or by the deadline as directed by the Authority.

The applicant shall notify the affected residents/developers of the scheduled resurfacing works before commencement.

The applicant shall bear the cost for lowering/raising of utilities manhole/s on public streets as and when required by the Authority and shall also liaise with the respective utilities owners on the lowering/raising of affected utilities manhole/s on public streets.

The following are conditions for the type of reinstatement that is required for carriageway. Notwithstanding these conditions, the Authority may specify any other conditions as and when it deems necessary.

Milling and patching/ hot in-place resurfacing of asphalt concrete to the carriageway shall comply with the following:

• Minimum thickness of 50mm for W3B and 75mm for steel slag is to be laid.

• The area shall cover the full width of the affected lane within this area.

• If any two or more openings are less than 30 metres apart, the mill-and-patch/ hot in-place resurfaced area shall include the area between these openings. The area shall form a rectangular segment at full lane width covering the affected lanes.

• For opening that affects yellow box, pedestrian crossing or road hump, the full extent of the road markings shall be re-marked.

• For temporary road diversion, full width carriageway shall be resurfaced when the affected carriageway is realigned to the permanent alignment.

• For openings in front of entrance driveway and side roads, the milling and patching/ hot in-place resurfacing shall cover full width of affected entrance driveways and side roads/accesses. (“STOP” line shall be taken as reference for side roads / access).

Longitudinal profile of the top surface of the reinstated trenches shall meet the International Roughness Index (IRI) values specified in the Material & Workmanship (M&W) Specification published by LTA.

For reinstatement of cross trenches, the reinstatement of the road surface shall be completed so that it is flat and flush with the surrounding adjacent surface. A 3-meter straight edge shall be used to check the flatness of the completed surface with the surrounding adjacent surface. The construction tolerances at the edges and the surface of the reinstatement shall not exceed ±5mm.

The reinstatement of footpath shall meet the following requirements:

• The reinstatement shall cover the full width of the footpath according to details as shown in the latest issue of LTA’s Standard Details of Road Elements.

• The length of the footpath reinstatement shall be at least 1 metre. However, if there is more than one reinstatement within a single 6 meter stretch, the area between them has to be reinstated.

  

• The new tiles to be used for reinstatement to the footpath shall match existing colours and texture of surrounding tiles. If such tiles are not available/out of production, the applicant shall propose an alternative design for the Authority's approval prior to commencement of works.

• The tiled footpath shall cover 6 metre length or to the nearest joint, whichever is shorter, at full width of the footpath, forming a rectangular segment.

• The reinstatement of footpath ramp shall be in accordance with the current standards of the Authority for barrier-free accessibility.

All rigid pavement of carriageway shall not be opened. If the opening is unavoidable, the applicant has to reinstate the rigid pavement according to details shown in the latest issue of LTA’s Standard Details of Road Elements.

Rigid pavements are to be constructed in panel of individual full lane width at minimum length 10 meter measured from the nearest expansion joint, or the full length between nearest expansion joints, whichever is shorter.

The road lines affected by road openings shall be restored with thermoplastic road marking materials within 3 days upon completion.

However, the critical road lines including the ‘STOP’ lines, pedestrian crossing and arrow markings shall be restored immediately upon completion of works and before the reinstated area is opened to traffic.

For interim reinstated areas that require surfacing works such as mill-and-patch works at a later date, stick on materials or any other materials approved by the authority may be used to temporarily restore the affected road lines.

The Road Works Regulation & Licensing Division (RWRL) must be notified in advance of the commencement of the works if any pavement markings for school zone e.g. Street Print are affected by works.

The Deputy Director, ITS Operations Division, must be notified in writing 7 days in advance of the commencement of the works if any traffic detector loops/ feeder cables for traffic lights/ intelligent road studs are affected by the works. Please refer to section 8.6.4 for address.

For emergency opening, the applicant has to notify the Deputy Director, Traffic, Street and Commuter Facility Lighting Division via fax (fax no. 63328127) and telephone (at tel no. 63328129/ 63328130/ 63328131) immediately if detector loops/ intelligent road studs are affected.

Any accidental damage to detector loops/ feeder cables for traffic lights/ intelligent road studs must also be reported immediately in writing and by fax to:

LTA Traffic, Street and Commuter Facility Lighting Division

181, River Valley Road

ITS Operations, Level 4

Singapore 179034

The Deputy Director, Road Pricing Systems Division (RPS), must be notified in writing 14 days in advance of the commencement of the works if any Electronic Road Pricing (ERP)’s structure/ associated infrastructure (i.e. controller housing, OG box and black & white strips) are affected by the works.

The applicant must report to LTA Road Pricing Systems Division in writing via email address: ERP_Ops_Support@lta.gov.sg or phone (92957316) immediately for any incidental damage to ERP’s structure/ detector loops, etc.

The Authority has used special materials for the roads and footpaths where necessary. If the Applicant's works affect such roads and footpaths, the Applicant shall reinstate with the same material or materials specified by the Authority. Thus the applicant shall have to satisfy the Authority that he has the expertise and the materials available to do a satisfactory reinstatement of such roads and footpaths before commencement of works.

For road pavement on reclaimed land at Tuas, the reinstated work shall comply with the permitted materials and layer thickness as specified in Figure 8.2 Pavement Reinstatement Details for Road Pavement on Reclaimed Land at Tuas.

This section stipulates the basic standard of quality of materials and workmanship required by the Authority. In the absence of any other technical requirements, the latest edition of the LTA’s Standard Details of Road Elements and/ or the Material and Workmanship Specifications published by LTA shall prevail.

Unless otherwise specified, all materials, fittings, workmanship, construction and installations for the Works, shall comply with the appropriate standard issued by the Standards, Productivity and Innovation Board (SPRING Singapore). If such a standard does not exist, then the appropriate standard issued by the British Standards Institution shall be used. Where relevant provision does not exist, the Contractor shall submit appropriate equivalent standard to the approval of the Engineer.

Applicant is required to check and declare that the condition(s) of final reinstatement work is in full compliance with the prevailing regulatory requirements, Code of Practices, Standard Details of Road Elements and/ or the Material and Workmanship Specifications, published by the Authority. In the event that the final reinstatement is not in compliance with requirements, the Authority reserves the right to require Applicant to carry out necessary rectification accordingly to the Authority’s satisfaction.

All backfill materials within the road carriageway shall be granular material (see Section 9.2.2), flowable concrete, or foamed concrete.

Any other materials not stipulated above are unsuitable materials and shall not be used for back-filling. Unless otherwise approved by the Authority, materials indicated below are not acceptable:

1. material from swamps,

2. peat, logs, stumps, perishable material and soft clay,

3. material susceptible to spontaneous combustion,

4. soil of liquid limit exceeding 70 and/or plasticity index exceeding 35,

5. excavated asphalt concrete from existing road.

Granular materials that are used as backfill materials shall conform to the following characteristics:

1. Not more than 35% fines passing through sieve 75µm,

2. The fraction passing through sieve 75µm shall have plasticity index (maximum) and liquid limit 35 (maximum),

3. Dry density to be 1760 kg/ m³ (minimum).

All aggregates used for foamed concrete shall pass a 3.75mm BS sieve and shall not contain more than 5% by weight of clay contamination, determined in accordance with BS 882:1983 Clause 5.4.

All foamed concentrates shall be diluted in accordance with the manufacturer's recommendations and aerated using an appropriately designed foam generating system. Foam concentrates and diluted solutions shall be stored according to the manufacturer's recommendations and used within the recommended shelf life.

Subject to experience of their suitability that is obtained by prior development testing, all accelerators, plasticisers, water reducing agents and other admixtures shall be used in accordance with the manufacturer's recommendations.

Foamed Concrete mixes shall be prepared using a ready - mixed base mortar delivered to site, and in accordance with a mix formulation proven by prior development testing.

The foamed concrete shall achieve a minimum density of 1050kg/m³. Plastic sheeting, etc., shall be provided to protect the existing utility apparatus so that foamed concrete is prevented from flowing into and blocking any damaged apparatus that exist within, or are immediately adjacent to the excavation.

Reinstatement of the surface layers shall not be carried out until the foamed concrete has attained sufficient strength to allow compaction of the asphalt materials.

Ready-mix flowable fill is a mixture of Portland cement, aggregates, water and mineral admixtures. Flowable fill has a cementitious content that is lower than that of Portland cement, and has a reduced strength development for easy removal. Chemical admixtures may also be used to modify the fill's performance properties in strength, flow, set and permeability.

The mix shall be prepared using a ready-mix base mortar delivered to site. Mineral admixtures shall be pozzolanic materials used in standard ready-mix concrete production.

Chemical admixtures shall be liquid or powder form used in standard ready-mix concrete production or other permissible products as follows:

1. High air generators specifically designed for flowable fill to lower unit weights, reduce shrinkage and subsidence, and to control compressive strength.

2. Air entraining admixtures conforming to ASTM C-260.

3. High-range water-reducers conforming to ASTM C-494 Type F or G.

4. Accelerating admixtures conforming to ASTM C-494 Type C such as calcium chloride. However where metals are present in concrete or embedded members, accelerators that are non-chloride and non-corrosive shall be used.

Pipes and all other members to be encased in the flowable fill shall be temporarily secured in place to prevent displacement during the flowable fill placement. To reduce hydrostatic pressure and limit displacement potential, a high air generator admixture in the flowable fill mixture is recommended to lower unit weights.

Cement used for public streets shall be ordinary Portland cement, rapid hardening Portland cement complying with SS26, sulphate resisting Portland cement to BS4027, Supper- sulphated cement to BS4248 or low heat Portland-blast-furnace cement to BS4246.

Cement of different manufacture and of different types shall not be used in the same mix.

Cement that becomes lumpy or has deteriorated shall not be used for concreting and shall be removed from site immediately.

Fine aggregate shall be natural sand or crushed stone sand complying with the requirements of SS31. Coarse aggregate shall be gravel or stone complying with SS31.

Water shall be clean fresh water free from chemical and organic impurities.

Concrete mixes shall generally comply with the specification in Table 9.1.

Table 9.1 Specifications for Concrete Mix for different grades of concrete.

Concrete shall be thoroughly mixed in a batch type mechanical mixer. No concrete shall be mixed by hand. For amount in excess of 3 m³, no in-situ mixing is allowed. Ready-mixed concrete, conforming to SS 119 and the specification as listed in Table 9.1, might be used.

The reinforcement shall be either (i) steel complying with SS 2, (ii) steel complying with SS 18, or (iii) steel fabric complying with SS 32.

Coarse Aggregates for asphalt concrete shall be clean, wellgraded, angular, crushed stone or steel slag of approved quality. They shall be free from dust, dirt and other deleterious materials; and there shall not be an excess of flat, elongated or weathered pieces. The properties of coarse aggregates shall conform to the requirements in Table 9.2 and 9.3.

Fine aggregates for asphalt concrete shall consist of clean, sound durable, angular particles produced by crushing stone, slag or gravel and shall be free from coatings of clay, silt or other deleterious materials. They shall meet the soundness and wear requirements as specified for coarse aggregate.

Filler, in addition to those naturally present in the aggregate, shall meet the requirements of ASTM D242.

Table 9.2. Requirements for Properties of Coarse Aggregate (Granite Stone)

Table 9.3. Requirements for Properties of Coarse Aggregate (Steel slag). Granite filler may be used if steel-slag filler is not available.

Bitumen Emulsion shall be homogeneous and rapid-setting cationic bitumen that conforms to the requirement of Table 9.4.

Bitumen shall be approved type petroleum bitumen of 60/70 penetration grade. No mineral matter other than that naturally contained in such bitumen shall be present. The bitumen shall be homogeneous, free from water and shall not foam when heated to 175 °C. The bitumen shall conform to the requirements of Table 9.5.

Table 9.4 : Requirements for Cationic Emulsified Asphalt

Table 9.5 : Requirements for Bitumen

For Mix Design, the aggregate grading for various types of mix design shall be in accordance with the mix design specification of Table 9.8.

Temperature of Hot Asphalt Concrete shall not be lower than 130°C at the time of laying.

Cold Instant Premix that conforms to BS4987: 1988 may be used in cases where the area is small (less than 1 tonne of premix required). The binder used shall be bitumen based; and shall contain resin, adhesive, polymers, and solvent. The mix design for base course of the aggregate grading and bitumen binder content shall conform to Table 9.6 and the following:

• Bitumen Binder Content: 3.6% to 4.2%

• Type of aggregate: Grit stone

  BS Sieve Passing	Percentage by mass
  28.00mm	100
  20.00mm	95 - 100
  14.00mm	65 - 85
  10.00mm	55 - 72
  6.30mm	39 - 55
  3.35mm	32 - 46
  300µm	7 - 21
  75µm	3 - 8

Table 9.6 Grading of Aggregates for Mix design for Base Course of instant premix

The mix design for wearing course of the aggregate grading and bitumen binder content shall conform to Table 9.7 and the following:

• Bitumen Binder Content : 5.0% to 6.0%

• Type of aggregate : Dolerite

  BS Sieve Passing	Percentage by mass
  10.00mm	100
  6.30mm	80 - 100
  3.35mm	25 - 45
  1.18mm	10 - 30
  75µm	2 - 9

Table 9.7 Grading of Aggregates for Mix design for Wearing Course of instant premix.

* Note: Only steel - slag aggregate is permitted. The use of granite filler is permitted if there is insufficient steel slag filler available.

The graded RCA shall be free from harmful contamination and conform to the following requirements.

1. Coarse aggregate shall consist of sound, tough, durable particles, free from adherent coatings of clay, organic matter and other deleterious substances. The properties of coarse aggregate shall comply with the following requirements:

2. The gradation of RCA and the liquid limit, plasticity index and linear shrinkage of fine aggregates shall comply with the requirements as shown in Table 10.3 and Clause 10.3.2.3 of the LTA’s Materials and Workmanship Specification (Revision A8, 2008).

Table 9.9. Requirements for Properties of Recycled Aggregate

* Fine is particle size fraction of an aggregate which passes the 0.063 mm sieve

** Impurities such as ferrous and non-ferrous metal, brick, plastic, wood, ceramic, asphaltic material and soil shall be removed. The percentage of impurity by mass shall not exceed 5%.

Recycled concrete aggregate (RCA) dust is produced from the processing of construction and demolition waste. It shall be produced from a proper processing plant. The processing shall include but not limited to the following processes:

1. Crushing via primary and secondary crushers into the required particle sizes

2. Removal of ferrous metals via magnetic separator

3. Removal of foreign materials such as brick, ceramic, wood, plastic and asphaltic material

4. Sieving of RCA into the required sizes

RCA dust shall consist of mainly granite aggregate and cementitious materials such as cement paste and mortar. It shall contain no more than 5% (by mass) of impurities such as metal, brick, ceramic, wood, plastic and asphaltic material. The gradation of RCA dust shall comply with the grading limits as shown in the Table below:

Note: Based on LTA Materials & Workmanship Specification for quarry dust (2001)

In addition, RCA dust shall have a minimum soaked California Bearing Ratio of 30% when tested in accordance with BS 1377, using the dynamic compaction method with a 4.5kg rammer at the dry density and moisture content likely to be achieved in the field.

The semi-rigid pavement shall consist of an open graduated asphalt with a void between 25 % to 30 % by volume (Marshall), flood filled with high strength cementitious mortar possessing high fluidity and internal cohesion. It shall achieve a compressive strength of 7-10 MN/m² at 28 days and a flexural strength of approximately 3.5 MN/m². The components of the open graduated asphalt are listed in Table 9.10.

Table 9.10. Components of open-graduated asphalt.

Coarse aggregates of semi-rigid pavement shall consist of clean, angular, crushed granite stone of approved quality, free from dust, dirt and other deleterious materials; and free from an excess of flat, elongated or weathered pieces. The proportion of the coarse aggregates shall conform to Table 9.11.

Table 9.11. The proportion of the coarse aggregates in semirigid pavements

Lime filler used shall be hydrated lime.

Cellulose Fibres shall be raw cellulose, long fibres and grey possessing the following properties:

• Cellulose Content : Approximately 80%

• Average fibre length : 1,100um

• Average fibre thickness : 45 um

• Bulk density : 20g/l to 40g/l

• Residue on ignition: approx. 15%(at 850°C,4 hrs)

• pH - value: 7.5±1

  Air jet sieve analysis (DIN 53734) shall have the following residue on the screen:

  Size of Interior Mesh Aperture	Max % of residue
  300 μm	Max 60%
  32 μm	Max 99%

Table 9.12. Air - jet Analysis of Cellulose Fibres.

High Strength Cementitious Mortar shall consist of a dense packing of cementitious inorganic material and shall be mixed with water to form a free flowing mortar having a high internal cohesion. It shall conform to the following requirements:

• Compressive strength:

  1 day: 55 MN/m²

  28 days: 110 MN/m²

• Flexural strength: 15 MN/m³

• Density: 2200kg/m³

• Water Absorption (DIN 52103): 6.9 by weight %

• Water Absorption ( drying-out of concrete at 20°C and 65% relative humidity): 0.5 by weight %

• Chemical resistance: 3 to 5 times more resistance than grade 50 concrete

• Setting time : 8 to 12 hours

Mixing of Open Graduated Asphalt-The components shall be added in the following sequence:

1. Crushed aggregates and cellulose fibres

2. Lime filler

3. Bitumen

The mixing temperature shall be approximately 165°C at a mixing time of between 39 and 45 seconds per batch. Storing of mix in the silo is not allowed.

Mixing of High Strength Cementitious Mortar - Amount of water to be added shall be approximately 4.7 kg per 25 kg of high strength cementitious mortar dry powder, or the water/binder ratio shall range between 0.266 and 0.278.

Concrete surface paving on footpath shall be approved sprayed-on acrylic modified UV stable pigmented cementitious topping with minimum thickness of 1 mm, minimum cured compressive strength of 45 N/mm² and skid resistance not less than 50.

Concrete Surface paving on carriageway shall be approved spray-on acrylic modified UV stable pigmented cementitious topping with minimum thickness of 1mm, minimum cured compressive strength of 60 N/mm² and skid resistance not less than 65.

Thermoplastic materials shall be used for all road markings. The material and site performance requirements for hotapplied white, yellow, red and black thermoplastics road marking materials and their constituents shall comply with Singapore Standard SS 589: 2013 - "Specification for hotapplied thermoplastics road marking materials - Materials, performance and application" or the latest Singapore Standards (SS).

The materials on definitions of coefficient of retro-reflected luminance, luminance coefficient, tables in field performance requirements and sampling are reproduced from SS 589 : 2013 – ‘Specification for hot-applied thermoplastic road marking materials – Materials, performance and application’ with the permission from SPRING Singapore. All rights reserved.

The ratio of the luminance of the field thermoplastic road marking in the direction of observation by the luminance at the perpendicular to the direction of the incident light.

The ratio of the luminance of the field thermoplastic road marking in the given direction by the illuminance on the field under diffuse illumination. The field measurement of Qd value shall be obtained using a portable device complying with ASTM E7170.

The field measurement of coefficient of retro-reflected luminance RL value shall be obtained using a portable device complying with ASTM E1710. The measurement of RL of thermoplastic road marking during wetness shall in accordance with ASTM E2177. The average initial RL values for thermoplastic road markings in dry and during wetness after installation shall conform to Table 9.15. It is generally agreed that the initial measure is best taken approximately one to two weeks after application. This allows time for the waxes, paint dust and coatings to be removed under traffic. It also provides time to test whether markings have been applied successfully and glass bead retention is satisfactory. The number of measurement shall conform to Table 9.14.

Take three portions, each having a mass of not less than 4kg, from the outlet of a preheater or laying apparatus, discarding the first and last 5% of the charge. Combine the three portions in a clean container clearly labelled with the contractor’s name, type of material, site and date. Do not apply heat at any stage of the sampling process once the road marking material has issued from the melting or laying apparatus. Record the temperature of the road marking material at the time of sampling. Keep half the sample for evidence in case of dispute.

Test panels shall be made of aluminium at least 850mm long, 1500m wide, and 0.6mm thick, prepared for test by solvent cleaning. Prepare the panel and apply the paint to the panel to give a dry film thickness of 1.5mm without glass beads.

The type and number of tests shall follow Table 9.13, 914 and 9.15:

Table 9.13 Number of tests required for different length of opening

Table 9.14 Number of measurement for Q_d, R_L and thickness

Table 9.15 R_L for road marking in dry condition and during wetness at initial application and after 5 months

The cost incurred in carrying out the various tests is to borne by the Applicant. All test results shall be submitted to the Authority electronically through the LTA.PROMPT.

The Authority at its own discretion may carry out additional tests whose cost shall be borne by the Applicant.

All tests, except the Depth and Thickness Tests, shall be carried out by Productivity Standards Board or its accredited laboratories.

The depth of utilities and the thickness of the reinstatement materials shall be determined by non-destructive equipment or by the open-cut method. The open-cut method shall be carried out before the milling and patching process.

On completion of the test(s), the Applicant shall submit the result(s) to the Authority indicating the location(s) tested.

The Depth and Thickness Test result(s) shall be endorsed by the Applicant.

The field density of the cored samples shall be used to determine the degree of compaction of the asphalt concrete.

The retro-reflectivity of thermoplastic materials shall be measured in the field by the retroreflectometer. The retroreflection readings shall conform with Singapore Standard SS 589: 2013 - "Specification for hot-applied thermoplastics road marking materials - Materials, performance and application".

The compressive strength of concretes shall be measured by crushing tests on nominal 150 mm cubes. All sampling, curing and testing of cubes shall be carried out in accordance with BS 1881. The compressive strength of concrete shall comply with Table 9.1 of Section 9.3.

Notwithstanding the above, the Authority reserves the right to instruct the Applicant to core any number of samples from any portion of the works for the purpose of determining the concrete compressive strength. The minimum depth of cored concrete sample is 75 mm for footpaths, and 100mm for slabbed-over-drains and rigid pavements. The Applicant shall supply and backfill voids with similar material left by the coring.

The minimum average value of the 28th day in-situ compressive core strength shall not be less than 18 N/mm² for 75 mm thick cast-in-situ concrete footpaths and 22 N/mm² for 125mm thick slabbed-over-drains.

The maximum allowable thickness tolerances for footpath, slabbed-over-drain and rigid pavement is ±5mm.

The quality of all the precast concrete units shall comply with LTA’s prevalent Materials and Workmanship Specification. The number of test(s) required shall conform to Table 9.13 of Section 9.9.1.

For Precast Concrete Slab - When tested in the manner described in Appendix C of BS 368, the average increase in weight of the test pieces from each slab by absorption of water shall not exceed the appropriate values in Table 3 of BS 368.

For Precast Kerbs and Channels - When tested in accordance with Appendix C of BS 340, none of the three specimen absorptions shall exceed the appropriate values in Clause 9.3 of BS 340.

The Extraction Test to determine the bitumen content in asphalt concrete shall conform to Table 9.8 of Section 9.4.6 and the number of test(s) shall conform to Table 9.13 of Section 9.9.1.

The sieve Analysis Test determines the grading of aggregates in asphalt concrete, and shall conform to Table 9.8 of Section 9.4.6.

The skid resistance value shall comply with Materials & Workmanship Specification for Civil & Structural Works, Code of Practice for Works on Public Streets, Singapore Standard SS 589 : 2013 - " Specification for hot-applied thermoplastics road marking materials - Materials, performance and application, or the latest Singapore Standards (SS).

The Authority may require the Applicant to core any number of samples from any portion of the works for the purpose of examination and testing. All cored samples shall be neatly cut by a 100 mm diameter core drill. The Applicant shall supply and backfill all voids with similar materials left by coring.

The cored samples shall be used to determine the field density and for the Extraction Test shall conform to Table 9.8 of Section 9.4.6.

The Authority may require the Applicant to core at the rate of one per 100 m³ of graded RCA laid and at least 3 samples shall be taken for the purpose of examination and testing. For site with more than 400 m³ of graded RCA laid in a day, a maximum of 5 samples shall be taken. All cored samples shall be neatly cut by a 100 mm diameter core drill. The Applicant shall supply and backfill all voids with similar materials left by coring.

The Authority may require the Applicant to take at least 3 samples of RCA dust at each site in a day for the purpose of examination and testing. The samples shall be tested for aggregate grading. These samples shall be marked with the date laid and location identification, and test at an accredited laboratory.

The Authority may require the Applicant to conduct nondestructive tests where appropriate. The type of nondestructive tests may either be required by the Authority or be proposed by the Applicant. When proposing the type of test, the Applicant shall prove to the Authority's satisfaction that the test can:

• determine the thickness of the layers of reinstatement for pavement reinstatement;

• determine the type of apparatus, its depth and location.

ADMINISTRATION OF DEMERIT POINTS SYSTEM

The main objective of the demerit points system is to encourage desirable good performance, quality of works and timely completion of works.

Under Regulation 9 of the Street Works (Works on Public Streets) Regulations, demerit points will be meted out to the contractor who has, in the course of carrying out any works on any public street, committed any of the defaults as listed in the Schedule of the Street Works (Works on Public Streets) Regulation.

The Authority will monitor and assess the contractor’s performance. Contractors who accumulate 200 or more demerit points within a calendar month (i.e. 30 days) will be suspended from carrying out new work on public streets.

Any contractor who has, within any one calendar month been awarded a total of 200 or more demerit points will be suspended by the Authority.

The length of the suspension depends on the number of suspensions that the contractor already had in the past two years. Please see Table below.

During the period of suspension, the defaulting contractor cannot be appointed for any new work application. However, the Authority will allow those ongoing works as listed in the Authority’s record to continue till completion. It is therefore important for the applicants/contractors to notify the Authority of the start of their work as it will have a bearing on the works that can be allowed to continue should the contractor be suspended.

The recipient of the Notice of Road Opening Infringement may appeal to Deputy Director, Road Works Regulations & Licensing Division, for a waiver of the demerit points within 14 days from the date of the Notice.

The appeal must be put in writing to the following address:

LTA Road Works Regulation & Licensing Division

71 Chai Chee Street

Block 1 #03-00

Singapore 468981

Submission Process for Permit to Carry Out Works on Public Streets

Format for use for Banker's Guarantee furnished by the Applicant Please use exact wordings

Format for use for Banker's Guarantee furnished by the Contractor Please use exact wordings

Contractor Category (Workheads/License Types) and Associated Work Type