Lateral Load Response of Reinforced Concrete Buildings Constructed on Clay Soil with Weak Zones

Abstract

Buildings in some conditions suffer from structural issues caused by foundation soilinhomogeneity. The main cause of an inhomogeneity in soil profile is the presence of voidsor very weak large pockets. The present paper deals with the structural behavior of concretebuildings, exposed to transverse loading such as seismic loads, when constructed on claysoil with predefined weak zones (voids). The finite element program ANSYS was used tostudy the effect of an underground void of different sizes and locations. A comprehensivestudy of various parameters was conducted on six structures of different widths and heights,considering the underground void diameter and void location. The effects of undergroundvoids on building natural periods and structural response to static lateral loads wereinvestigated. According to the studied cases, it was found that the void effect in increasingthe differential settlement almost fades at void eccentricity equals 1 to 3 times the structurewidth from the foundation center. Although the void effect in increasing lateraldisplacements at structure floor levels fades at void eccentricity equals 1 to 1.75 timesstructure width. The void effect approximately vanishes at void depth equals 1 to 3.5 timesthe structure width from the foundation level.

Keywords

• lateral loads
• underground void
• critical locations
• building width
• soil structure interaction