Effect of Shear Wall Arrangement and Frame Configuration on the Seismic Response of Vertically Irregular R.C. Building Frames

Abstract

Due to the increasing demand for infrastructure development in Saudi Arabia, high-rise reinforced concrete frames happen to be one of the obvious choices on account of their structural integrity and durability. The R.C. structural systems possess added advantage of reasonable construction as well as maintenance cost as compared to the other systems. R.C. frames are basically a structural network of R.C. beams and columns. These frames should provide the required resistance to both gravity and lateral loads through shear and flexural action between beams and columns. The analysis of the R.C. framed structures necessitates a realistic assessment of lateral loads acting on the structure. Based on the Saudi Building Code, the different location zoning maps of statistical seismic ground motions in Saudi Arabia will help eventually to predict the analytical response of structures during lateral loading action. In this study, a parametric investigation has been undertaken to study the effect of earthquake loads on R.C. frames with irregularities in the vertical plane located in Haql, Kingdom of Saudi Arabia. The lateral load resisting capacity of the structural systems is expected to be improved by using shear walls dual systems. The vertical plane irregularity, shear wall plan distribution, and the overall geometry configuration are the main variables. The focus is on the improvements of the overall stiffness, ductility, and rigidity of R.C. frames and their role in withstanding the lateral loads. Ten geometric configurations presented by five slenderness ratios of 1, 1.5, 2, 2.5, and 3. five aspect ratios of 1.2, 2.4, 3.6, 4.8, 6.0 are considered. The dynamic analysis was undertaken using finite element technique-based commercial software package STAAD Pro. Results reveal that the increase in the slenderness ratios for the regular framesleads to a slight increase in shear response but higher displacements and drift. The increase in plan aspect ratio results in a significant increase in the frames shear response with almost convergent displacements. Also, the regular and irregular frames of smaller slender ratios exhibit higher lower-story displacements and drifts than the frames with higher slender ratios. The bottom soft story frame configurations appear to be more vulnerable as compared to frames having irregularity at the middle and top level. The shear wall frame configurations have shown a significant increase in the lateral deformation behavior of the soft story frame cases. The core walls arrangement emerges as the optimum configuration with better performance over the corner and edge configurations