- shrinkage and temperature reinforcement shall be spaced not farther apart than 5 times the slab thickness, or 450mm
- spacing of prestressed tendons shall not exceed 1.80m
T-BEAM CONSTRUCTION
- the flange and web shall be built integrally or otherwise effectively bonded together
- width of slab effective as a T-beam flange on each side of the web shall not exceed:
* 1/4 the span length of the beam,
* 8 times the slab thickness, or
* 1/2 the clear distance to the next web
- for beams with a slab on one side only, the effective overhanging flange width shall not exceed:
* 1/12 the span length of the beam,
* 6 times the slab thickness, or
* 1/2 the clear distance to the next web
- transverse reinforcement shall be spaced not farther apart than 5 times the slab thickness, nor 450mm
JOIST CONSTRUCTION
- ribs shall not be less than 100mm in width and shall have a depth of not more than 3½ times the minimum width of rib
- clear spacing between ribs shall not exceed 750mm
- slab thickness over permanent fillers shall not be less than 1/12 the clear distance between ribs nor less than 40mm
- when removable forms or fillers are used, slab thickness shall not be les than 1/12 the clear distance between ribs, or less than 50mm
- where conduits or pipes are embedded within the slab, slab thickness shall be at least 25mm greater than the total overall depth of the conduits or pipes at any point
REQUIRED STRENGTH
- dead load and live load
* U = 1.4D + 1.7L
- dead load, live load and wind load
* U = 0.75 (1.4D + 1.7L + 1.7W)
* U = 0.9D + 1.3W
- dead load, live load and earthquake load
* U = 1.3D + 1.1L + 1.1E
* U = 0.99D + 1.1E
STRENGTH-REDUCTION FACTOR
- flexure without axial load, 0.90
- axial tension and axial tension with flexure, 0.90
- axial compression and axial compression with flexure:
* spiral reinforced, 0.75
* tie reinforce, 0.70
- shear and torsion, 0.85
- bearing on concrete, 0.70
- post-tensioned anchorage zones, 0.85
MINIMUM THICKNESS OF NONPRESTRESSED BEAMS OR ONE-WAY SLABS UNLESS DEFLECTIONS ARE COMPUTED (members are not supporting or attached to partitions or other construction likely to be damaged by large deflections)
- solid one-way slabs:
* simply supported, L/20
* one end continuous, L/24
* both ends continuous, L/28
* cantilever, L/10
- beams or ribbed one-way slabs:
* simply supported, L/16
* one end continuous, L/18.5
* both ends continuous, L/21
* cantilever, L/8
- for Fy other than 415Mpa, the values shall be multiplied by (0.4 + Fy/700)
DISTANCE BETWEEN LATERAL SUPPORTS OF FLEXURAL MEMBERS
- spacing of lateral supports for a beam shall not exceed 50 times the least width b of compression flange or face
LIMITS FOR REINFORCEMENT OF COMPRESSION MEMBERS
- minimum number of longitudinal bars in compression members shall be 3 for bars within triangular ties, 4 for bars within rectangular or circular ties, and 6 for bars enclosed by spirals
SPACING LIMITS FOR SHEAR REINFORCEMENT
- shall not exceed d/2 in non-prestressed members and 3/4h in prestressed members or 600mm
SPLICES
- lap splices shall not be used for bars larger than 36mm diameter
- lap splices of bars in a bundle shall be based on the lap splice length required for individual bars within the bundle
- individual bar splices within a bundle shall not overlap
- entire bundles shall not be lap spliced
- bars spliced by non-contact lap splices in flexural members shall not be spaced transversely farther apart than 1/5 the required lap splice length, or 150mm
- splices shall be staggered at least 600mm
WALLS
- minimum ratio of vertical reinforcement area to gross concrete area shall be:
* 0.0012 – deformed bars not larger than 16mm diameter with a specified yield strength not less than 420Mpa, or
* 0.0015 – for other deformed bars, or
* 0.0012 – for welded wire fabric (plain or deformed)
- minimum ratio of horizontal reinforcement area to gross concrete area shall be:
* 0.0020 – deformed bars not larger than 16mm diameter with a specified yield strength not less than 420 Mpa, or
* 0.0025 – for other deformed bars, or
* 0.0020 – for welded wire fabric (palin or deformed)
- in addition to the minimum reinforcement required, not less than 2-16mm diameter bars shall be provided around all window and door openings. Such bars shall be extended to develop the bar beyond the corners of the openings but not less than 600mm
NON-BEARING WALLS
- thickness shall not be less than 100mm, or not less than 1/30 the least distance between members that provide lateral support
MINIMUM FOOTING DEPTH
- depth of footing above bottom reinforcement shall not be less than 150mm for footings on soil, or not less than 300mm for footings on piles
TRANSVERSE REINFORCEMENT (HOOPS)
- the first hoop shall be located not more than 50mm from the face of a supporting member
- maximum spacing of the hoops shall not exceed:
* d/4
* 8 times the diameter of the smallest longitudinal bar
* 24 times the diameter of the hoop bars
* 300mm
- where hoops are not required, stirrups shall be placed at no more than d/2 throughout the length of the member
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