Effect of Foundation Soil Flexibility on The Dynamic Behavior of Multi-Story Concrete Buildings

Abstract

During earthquakes in the last few decades, it has been revealed that since earthquakes are one of the most common natural disasters, which affect both human life and property, hence design codes shall study all of its parameters that affect it from all sides. To avoid negative effects of earthquake, the nonlinear response of structures under dynamic loading should be accurately modelled in order to ensure safe and sound design. Reinforced concrete structures designed to withstand earthquakes must have enough strength and stiffness to control deformations and prevent any possible collapse. Recent seismic design codes include response modification factor (R) in definition of lateral forces used for seismic design to reduce the design elastic spectral acceleration to account for its components yielding. Response modification factor (R) reflects the structure capacity to behave in-elastically without collapsing. In fact, the (R) factor is a combined effect of over strength, redundancy and ductility. Response modification factors play an important role in the seismic design. No other parameter, in the design base shear equation, affects the design actions in a seismic framing system similar to the value assigned for R-factor, (Anand & Kumar, 2018). However, it has been revealed that the seismic behaviour of a structure is highly influenced, not only by the response of the superstructure, b