An Analytical review of Capacity Based Design of four storied R. C. C. framed Building containing Soft Story at Ground Floor

Abstract

If any storey has less resistance to earthquake forces in comparison to the other storeys, it is known as  a soft-storey. The soft  storey can occur at any storey level. It generally occurs at the ground level where distances between columns are provided for parking or any other use. As per  IS 1893 “A soft storey is the storey in which the lateral stiffness is having less than 70 percent of stiffness in the storey above or having less than 80 percent of the average lateral stiffness of the three storeys above.  Buildings having soft stories are extremely sensitive to earthquake damages. Such   building swings back and forth producing high stresses in column  members. In case, columns are incapable of taking  these stresses or do not posses enough ductile property, they could get damaged. This can  lead   severe damages to the building. This problem is  known as inverted pendulum.

Some major  earthquakes in which damages had been because of soft storey  are : 1. The San Francisco Earthquake occurred in 1906   2. The Bingol, Turkey Earthquake which occured on the the 1st of May 2003  3. 2001 Bhuj earthquake, India