Reliability Based Design Of Two-Way Slab In Comparison With Design Based On BS 8110 (1997)

This research presents the comparison between Reliability and deterministic design of two-way solid slab in accordance with BS8110 (1997). First Order Reliability Method (FORM) and the theory of Statistics are reviewed and adopted for designing the floor to a pre-determined safety level using a FORTRAN subroutine created and linked with the reliability software (FORM5). Reliability and deterministic design yielded satisfactory results for long span (mid-span and continuous edge) and short span (mid span only) with average safety index of 3.20 in bending and 1.48 in deflection which satisfies the JCSS (2000) code’s requirement. Reliability design yielded an economical section in the other of 10% while deterministic design yielded an unsatisfactory result for short span (continuous edge only). This revealed the weakness in ultimate limit state (ULS) design of the two-way slab along the shorter span (continuous edge only). Correction factor was also proposed to counter this weakness.