Effect of Soil–Structure Interaction on Nonlinear Dynamic Response of Reinforced Concrete Structures

Abstract

Investigating the nonlinear dynamic response of reinforced concrete (RC) structures is of significant importance in understanding the expected behavior of these structures under dynamic loading. This becomes more crucial during the design of new or the assessment of the existing RC structures that are located in seismically active areas. The numerical simulation of this problem through the use of detailed 3D modeling is still a subject that has not been investigated thoroughly due to the significant challenges related to numerical instabilities and excessive computational demand, especially when the soil–structure interaction (SSI) phenomenon is accounted for. This study aims at presenting a nonlinear simulation tool to investigate this numerically cumbersome problem in order to provide further inside into the SSI effect on RC structures under nonlinear dynamic loading conditions. A detailed 3D numerical model of full-scale RC structures considering the SSI effect through modeling the nonlinear frame and soil domain is performed and discussed herein. The constructed models are subjected to dynamic loading conditions and an elaborate investigation is presented considering different type of structures, material properties of soil domains and depths. The RC structures and the soil domains are modeled through 8-noded hexahedral isoparametric elements, where the steel bar reinforcement of concrete is modeled as embedded beam and truss finite elements. The Ramberg–Osgood constitutive law was used for modeling the soil domain. It was shown that the SSI effect can significantly increase the flexibility of the system, altering the nonlinear dynamic response of the RC frames causing local damages that are not observed when the fixed-base model is analyzed. Furthermore, it was found that the structures founded on soft soil developed larger base-shear compared to the fixed-base model which is attributed to resonance phenomena connected to the SSI effect and the imposed accelerograms.

The Effect of Soil-Structure Interaction (SSI) on Structural Stability and Sustainability of RC Structures

“…Soft soil is more significantly affected by SSI than medium or hard soil. A variation of Winkler's springs was used by numerous researchers to simulate soil-structure interaction [15]. Winkler's approach, while straightforward, is inaccurate because it does not accurately record deflections, particularly for the sub-structure.…”

Investigating the behaviour factor and seismic response of structural wall systems in low- to medium-rise buildings when soil-structure interaction is considered

“…Including soil-structure interaction (SSI) in the analysis may be essential to more accurately compute the building dynamic response (e.g. Mourlas et al 2020). SSI inclusion can improve the computed seismic response of a structure by period lengthening, kinematic effects, additional damping caused by soil hysteric damping and radiation damping.…”

Buckling Analysis of Thin-Walled Circular Shells under Local Axial Compression using Vector Form Intrinsic Finite Element Method

“…The stress-strain relationship in the plastic stage is complex, and it is difficult to accurately simulate the complete stress-strain relationship of materials. Generally, the hardening stage during plastic is commonly simplified as ideal elastoplasticity, the bilinear hardening model [19][20][21], the power hardening model [22,23], and the Ramberg-Osgood model [24][25][26]. Different hardening models have different characteristics, among which is ideal elastoplasticity, which will not harden after the material enters the plastic stage, and the stress-strain curve is parallel to the strain axis.…”