Theoretical Study and Nonlinear Finite Analysis of Four-Line Restoring Force Model for Double-Superimposed Slab Shear Walls

Abstract

This paper is concerned with the seismic behavior of a superimposed slab shear wall. Based on the test results of the specimens under low cyclic reversal loading, the formulas with respect to the top displacement and capacity of a shear wall in the consecutive loading process are derived. The concrete grade differentiation between the prefabricated layer and the cast-in-site layer of the shear wall is considered to improve the calculating precision. With the help of these equations, the extent of participation of the prefabricated concrete layers in the different loading stages is revealed, demonstrating a great confirmation of the test results. Two ideal conditions, utterly with and without connective effect between a combined interface, are considered to investigate the action of the bond–slip effect. On this basis, the finite element analysis is completed in the framework of OpenSees. Its quadrilinear restoring force model, with the consideration of the stiffness degradation and pinching effect, is established in this paper by various feature points from the theoretical derivation of capacities in different loading stages. The rationality of the restoring force model of the shear wall is testified by the satisfactory agreement of the test results and simulation results.

Keywords

• superimposed slab shear wall
• restoring force model
• pinch effect
• bond–slip effect