Influence of foundation flexibility on overall response and behavior coefficient of structures

The coefficient of behavior depends on various factors such as structural shape, material properties, dampingproperties, nonstructural members participation, structural uncertainty grade and structural overload. In thisresearch, the effect of foundation Flexibility on behavior factor of Concrete moment frame is investigated UsingSAP. Based on the results of changes in the behavior coefficient in terms of the shear wave velocities in the 5-story model, it is observed that, with the increase of the foundation s flexibility, a downward trend for the behaviorcoefficient is recorded. Accordingly, the coefficient of behavior from 6.2 in a steady state reached 4.9 in a flexiblefoundation, a decrease of 21%. Also, based on the results of changes in the coefficient behavior in terms ofdifferent shear wave velocities in the 10-story model, it has been observed that, with the increase of thefoundation s flexibility, a downward trend has been recorded for the coefficient of concrete structure. Thus, thevalue of the behavior coefficient from 6.1 in a steady state reaches 5.8 in a flexible foundation which is a decreaseof 5%. Finally, for the 20-storey model, it is observed that, with the increase of the foundation s flexibility, adownward trend has been recorded for the concrete behavior coefficient parameter. Accordingly, the behaviorcoefficient from 5.7 in the solid state reached 5.3 in a flexible foundation that is a decrease of 7%.

Keywords:

behavior coefficient , concrete frame , foundation flexibility