Advanced Precast Concrete System (APCS) is a construction method that:
- Shall adopt precast slabs.
- Applies 4 features (each with ≥ 65% coverage) under the ‘3S’ principles of Standardisation, Simplicity and Single integrated elements (refer to Table 1).
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Table 1: Features under the 3S principles
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Ref.
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Prefabricated components
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Denominator (project level)
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Unit
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1
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Integrated precast components comprising at least 2 structural / architectural elements (e.g. double bay façade-wall, beam-facade wall, multi-tier column/wall, precast household shelter, precast refuse chute, prefabricated bathroom unit, prefinished façade walls)
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All column/wall/façade wall/HHS/refuse chute/bathroom
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No./m
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2
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Mechanical connection for precast column/ precast wall (horizontal joints)(e.g. column shoes, grouted sleeves, spiral connector)
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All columns/walls
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No.
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3
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Mechanical connection for precast beam (e.g. telescopic beam connector, grouted sleeves) / Integrated prefabricated column and beam junction (e.g. Lotus Root system, slim floor system (e.g. Deltabeam))
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All beams
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No.
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4
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Mechanical connection for precast wall (vertical joints)(e.g. flexible loops)
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All walls
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No.
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5
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Mechanical connection for other precast components(e.g. mechanical connections for parapet walls, staircases*)
*Staircase flight and landing slabs shall be in precast concrete)
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All parapet walls / staircase flights
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No.
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6
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Large precast panel slab (e.g. panel size optimised for transportation, hollow core slab 2.4m width, double T slabs ≥ 2.4m width)
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Total project floor area
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m2
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Why use APCS
What to consider when using APCS
- Designed to handle stresses– The design of the precast concrete elements should take into consideration all stresses induced by the worst possible loads, movement, creep and shrinkage during the intended design life. The elements and their inserts or fixings should be capable of resisting stresses induced during manufacturing, lifting/handling, demoulding, transportation, storage and erection.
- Designed to be self-supporting– Precast concrete systems should also be designed to be self-supporting when placed in position, or to be safely supported in position with minimal falsework. Where falsework and temporary bracings are used, do ensure that these provide sufficient support to the precast concrete system to safely withstand loads which they may be subjected to.
- Fabrication – To facilitate transportation, precast concrete elements should be designed and fabricated into smaller elements and combined into bigger components whenever possible.
- Early contractor involvement– The project management team should consult with suppliers for training of erection crews before actual work begins. This is important as different connection systems may require specific tools, work methods and installation sequence to join and erect precast concrete components.
- Site / project management– As some of the proprietary products may have a long lead time, it is a good to exercise prudence by ordering such items well in advance with some contingency quantities.
Compliance to Regulation
- The design and construction of a building, including the precast concrete system, joints and connections, must comply to performance requirements prescribed in the Building Control Regulations.
Good practices on connection design and detailing, efficient automated production, and key considerations for production planning and site management.
Figure 1: Mechanical connections
Figure 2: Integrated beam-column junction connection