FAILURE INVESTIGATION OF REINFORCED CONCRETE CANTILEVER RETAINING WALLS

Abstract

Failure investigation was carried out on a reinforced concrete cantilever retaining wall using First Order Reliability Method (FORM). Four failure modes of the retaining wall were considered namely: overturning; sliding; bearing capacity and bending moment failure modes. The results of the analysis generally showed that the bending moment mode of failure was the most critical, followed by the sliding, the overturning, and by the bearing capacity modes of failure. Also, as the magnitude of the design load was increased by 50kN/m², the safety of the retaining wall increased by about 5%, 6% and 25% considering overturning, sliding and bearing capacity failure modes respectively. However, the safety of the structure increased by about 18% when the magnitude of steel reinforcement ratio was increased by 0.1%. Again, when the width of backfill was increased by about 15%, the safety of the structure decreased by about 25% and 34% considering overturning and bearing capacity failure modes; and increased by about 33% and 4% considering sliding, and bending moment failure modes respectively.