Seismic Reliability of the Shallow Footings against Bearing Failure of the Soil

Abstract

The paper presents the reliability of Reinforced Concrete (RC) shallow footings designed following the provision of Bangladesh National Building Code (BNBC) 2006. The principal objective of the study is to evaluate the reliability and corresponding failure probability of shallow footings designed following BNBC 2006. To achieve the objective of the study, three model buildings having different number of stories have been designed following the BNBC 2006. The bearing failure of soil has been used as performance function only. The statistical parameters of the design variables have been selected from available literatures. Monte Carlo Simulation (MCS) method has been used in the study. From the analytical investigation, it is found that the reliability of shallow footings highly depends on the Coefficient of Variation (COV) of bearing capacity of soil. The reliability index varies from 2.29 to 2.46 for COV of soil of 0.40 using a factor of safety of 2.50 under earthquake load. Reliability of footing increases with the decrease of COV of soil. It is also found that the performance of RC shallow footings designed using BNBC 2006 is poor under the earthquake load.