Influence of Soil Types and Importance Factors on the Seismic Response of RC Buildings”

Abstract

Experiences from previous earthquakes have shown that level of structural damages depends on soil characteristics where the structure is built on. Also, changing functioning and occupancy of the building after construction increases the scale of these damages. This study aims to investigate the effects of soil types B, C, and D and importance classes II, III and IV, given in the Eurocode 8, on seismic response of reinforced-concrete dual-framed structures evaluated by using linear static analysis. For this purpose, analysis and design of low and mid-rise buildings are considered. The analysis is performed with the equivalent lateral force procedure using Tekla Structural Designer software package. Combinations on analysis and design for different types of soils and different importance factors are done on a 4-storey dual framed and a 7-storey dual-framed structures, representing low and mid-rise buildings respectively. Results are compared considering the required total amount of reinforcement for each building alternative. It is quite clear that the demand for reinforcement of buildings built on soil type D is much higher than those in soil types C and B. Also the demand for reinforcement is much increased for buildings in importance class IV compared to those in Importance class III and II. The increase in reinforcement demand from a building type having Importance class II with soil type B to a building type having Importance class IV with soil type D is 109.8 % for 4- storeys and 134.96 % for the 7-storeys. Comparisons in cost of construction carried out taking in consideration demands for reinforcement of each alternative buildings, show an increase of 39 % for 4 storeys, and 47 % for 7-storeys, from building designed for II-B to building designed for IV-D.