Dynamic analysis of concrete coupled wall structures : a parametric study

Abstract

Concrete coupled wall structure is a system that can efficiently dissipate energy under the effect of lateral loads. It has been widely used in medium height buildings for several decades. While researchers have conducted both experimental and analytical investigations in order to improve the performance of concrete shear wall, there is a lack of systematic comparison of coupled wall behavior due to variation of parameters. Therefore, this report will carry out a parametric study by varying the height of the building, the degree of coupling (DC), and the shape of the wall piers. A computer-simulated study was carried out on the performance of coupled wall structures. The research process was divided into two phases with the first focusing on only on the shear wall system and the second on the interaction between the building and the core shear wall structure. Static pushover analysis was applied in Phase I, and acceleration response spectrum was employed in Phase II. The comparison of the results from both phases provided valuable insight on the structural behaviors of shear walls. The Phase I results showed that C-shaped coupled wall were more efficient than rectangular wall piers. From further investigation in Phase II, it was found that C-shaped wall with 15 degree opening could achieve the greatest stiffness. Same-size coupling beams could create DC in shorter buildings in Phase I, but the result was contradicted in Phase II testing. However, both Phases displayed the fact that shear stiffness played a more important role in affecting DC than flexural stiffness.

(cont.) Pushover analysis and response spectrum analysis both suggested that the DC of coupled wall structure decreased after concrete cracked and the horizontal force was then withstood by base moment. While concrete shear wall reduced lateral deflection of buildings, Phase II displayed the fact that floor frames could bend and form a sagging shape when interacting with coupled walls in an earthquake. Further study can be focused on more detailed modeling to investigate the behavior of concrete shear walls for efficient and economic design.