Ensuring Building Safety In An Urbanised Environment Singapore s Perspective. Ong See Ho Deputy CEO & Commissioner of Building Control

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1 Ensuring Building Safety In An Urbanised Environment Singapore s Perspective Ong See Ho Deputy CEO & Commissioner of Building Control

2 Outline BUILDING CONTROL ECO-SYSTEM WHAT DRIVES OUR STRUCTURAL SAFETY POLICIES DESIGN STAGE CONSTRUCTION STAGE COMPLETION OF CONSTRUCTION

3 Regulatory systems Design stage (pre-construction) Construction stage Completion Planning Approval Structura l Plan approval Permit to Commence Work Constructi on supervisio n Submissio n of asbuilt record plan Temporary Occupation Permit Development Control system Building Control system BCA is the agency responsible for goal-keeping within the Building Control system

4 Professionals involved (structural safety) Qualified Persons Professional Engineer (PE) (registered by Professional Engineers Board) Specialist PE in Geotechnical Engineering (registered by Professional Engineers Board) Accredited Checker (registered by BCA) Qualified Site Supervisor (registered by Institution of Engineers/Association of Consulting Engineers) Resident Engineer Resident Technical Officer

5 Qualifications For Professional Engineer (PE) A recognised civil/structural engineering degree (equivalent to a 4-year full-time undergraduate program) Minimum of 4 years of practical experience Passed 2 written exams and a professional interview For Specialist PE (Geotechnical) A PE in civil/structural engineering Minimum 7 years of practical experience Minimum 4 years of practical experience in geotechnical engineering

6 Qualifications For Accredited Checker 10 years of professional experience as PE, with experience in the design or construction of highrise buildings, precast, prestressed and steel structures buildings

7 Qualifications For Resident Engineer A recognised civil/structural engineering degree (4 years full time) For Resident Technical Officer a diploma in civil engineering from a recognised polytechnics

8 Parallel submission system Qualified Person Development Control (URA) Building Control (BCA) Other Agency Clearances Obtain provisional permission Obtain structural plan approval & permit Fire safety (SCDF) Obtain planning permission Obtain building plan approval Obtain completion certificates & occupation permit Drainage & sewerage (NEA) Roads & transport (LTA) Parks & trees (NParks) Others, e.g. services, ida etc.)

9 Structural safety policy drivers BUILDING SAFETY complex construction works are getting deeper and higher and closer to existing buildings Construction of KPE

10 Structural safety policy drivers BUILDING SAFETY events that shaped our safety regulations local failures (e.g. no supervision and peer review) 33 Dead Hotel New World

11 Structural safety policy drivers BUILDING SAFETY events that shaped our safety regulations local failures (e.g. underground building works) 4 Dead Nicoll Highway

12 DESIGN STAGE structural plan approval Structural plan approval Planning permission has been obtained Qualified Person (QP) - only a Professional Engineer (in the field of civil/structural engineering) can submit the plan An accredited checker (AC) from an Accredited Checking Organisation (ACO) will perform independent set of calculations (for project value > S$10 million) If there is excavation exceeding 6m deep, geotechnical aspects to be provided by specialist PE in geotechnical engineering BCA will also conduct random audit on QP and AC s submission

13 DESIGN STAGE structural plan approval Standards/Codes of practice Mainly British Standards and Singapore Standards From Apr 2013, structural design using Eurocodes is allowed Details to be shown on structural drawings Structural layout, with imposed load and dimensions of structural members Rebar details Connection details (welded or bolted) Specifications of the materials to be used Type of foundation to be used

14 DESIGN STAGE structural plan approval Details to be shown on pile layout drawings the types of piles and the specification of materials to be used; the location of piles and site investigation boreholes; the estimated pile penetration depth for each design zone; the minimum embedded pile length into competent stratum, where applicable; the unit skin friction and unit end bearing resistance for pile designs; the allowable pile bearing capacity before and after deduction of negative skin friction (if applicable) and details of pile joints; the allowable total and differential foundation settlement; the allowable vibration limit during pile installation; and the sectional details of piles and number and type of pile load tests and the location of ultimate pile load tests

15 DESIGN STAGE structural plan approval Details to be shown in structural design calculations Design Information Sheet giving a summary of important design information such as the design loads, codes of practice and assumptions Detailed analysis and Design of Structural Elements, including i. Foundation ii. all structural elements resisting horizontal forces iii. all vertical load bearing structural elements iv. transfer beams or plates v. typical beams and slabs vi. steel structure and critical connection details vii. any shaft, tunnel or cavern structure viii. retaining walls and supporting structures ix. the overall structural system under wind loads inputs and outputs from the computer analysis and design programme

16 DESIGN STAGE permit to commence work Joint application by the developer, Qualified Persons (Structural & Architectural) and builder A QP (Supervision), who is a PE, to be appointed to supervise the construction of structural works QP to appoint at least a Qualified Site Supervisor (either a Resident Technical Officer or a Resident Engineer) to assist him in supervising the structural works. A full time resident engineer is needed for project value > S$15million

17 CONSTRUCTION STAGE Builder s duty Construct according to approved plan Perform construction tests under the direction of QP (Supervision) Erect protective hoardings around the site and provide measures to protect the foundations of nearby building and excavation within the site Inform BCA if instrumentation readings exceeds critical values

18 CONSTRUCTION STAGE QP(Sup) & RE/RTO Supervise critical structural works, e.g. casting, piling, welding, etc Witness various construction tests, e.g. pile load test Keep site records such as material testing records, inspection records, attendance records, etc Report to BCA if instrumentation readings exceeded critical levels

19 CONSTRUCTION STAGE BCA officers BCA will conduct ad-hoc inspection during critical stages of construction, e.g. piling, excavation, demolition Check records on site and spot any contravention to Building Control Act and Regulations Revoke Permit or stop work for serious contravention

20 CONSTRUCTION STAGE Changes to design Major changes, e.g. removal of columns, reduced beam depth, change in structural layout, changes to unit skin friction parameter for piling, etc Submission of amendment plan is required. Changes cannot be effected on site until amendment plan is approved Minor changes, e.g. pile eccentricity within tolerance, minor change in beam dimension in localised area Submission of amendment plan is not required. Changes to be captured in record plan submission on completion

21 COMPLETION submission of record plans and apply for occupation permit To submit record plan upon completion of building works To capture minor changes during construction which do not require amendment plan Upon submission of record plans, developer could apply for Temporary Occupation Permit (TOP) in order for the building to be occupied. A joint inspection will be required before the grant of TOP

22 Thank you