Seismic performance of monolithic wall panel subjected to quasi-static lateral cyclic loading

Abstract

A half-scale of monolithic precast wall panel (4000x1350x125) together with foundation beam (3000x500x465) is designed to emulate the behaviour of a ductile cast-in-place concrete wall and designed accordance to New Zealand Standard (NZ3101). The slenderness ratio of wall panel is 30 and its aspect ratio is 3. The specimen is constructed on strong floor and tested under lateral quasi-static reversed cyclic loading from 0.1% drift up to 3% drift. The flexural strength of monolithic wall depends on the spacing of transverse and longitudinal bars in the potential plastic zone which located one-fifth height of wall. The percentage of longitudinal and transverse reinforcement ratios in this type of wall are 0.84% and 0.25%, respectively. These percentages of reinforcement bars are exceeding the minimum percentage of 0.24% as specified in BS 8110 which provide in both directions. Experimental results show that wall panel starts to crack at 0.25% drift and fully cracks on the surface of the wall at 1.0% drift. Spalling of concrete cover at bottom corner of the wall starts at 2.0% drift and become worse at 2.5% drift. The specimen reduces the strength degradation at 2.5% and longitudinal bars fractured at 3.0% drift. Overall results showed that monolithic precast reinforced wall panel performs well up to 1.0% drift (the wall behaving in elastic region) but performed badly after 1% drift until 3 % drift (under elasto-plastic and plastic regions) where strength degradation occurs.