Numerical Evaluation of Seismic Soil Pressures on Rigid Walls Fixed to the Bedrock

Abstract

Seismic soil pressures developed on a 7 m rigid retaining wall fixed to the bedrock are investigated using a finite element model that engages nonlinear soil intended materials available in OpenSees. This allows incorporation of the inelastic behavior of the soil and wave propagation effects in the soil-wall system seismic response. The nonlinear response of the soil was validated using the well-stablished, frequency-domain, linear-equivalent approach. An incremental dynamic analysis was implemented to comprehensively examine the effect of soil nonlinearity and input motion on the induced seismic pressures and to evaluate current code equations/methodologies at different levels of earthquake intensity. The results show that soil nonlinearity and seismic wave amplification may play an important role in the response of the soil-wall system. Therefore, methodologies that rely only on peak ground acceleration may introduce large bias on the estimated seismic pressures in scenarios where high nonlinearity and site amplification are expected.

Keywords:

• Seismic Pressures
• Rigid Walls
• Mononobe-Okabe
• Incremental Dynamic Analysis
• Spectrum Compatible Records
• Site Response

Acknowledgments

The statements, findings, conclusions, and recommendations are those of the authors and do not necessarily reflect the view of the US Nuclear Regulatory Commission.

Funding

This work was performed under awards NRC-HQ-12-G-38-0018 and NRC-HQ-84-14-G-0057 from the US Nuclear Regulatory Commission.

Additional information

Funding

This work was performed under awards NRC-HQ-12-G-38-0018 and NRC-HQ-84-14-G-0057 from the US Nuclear Regulatory Commission.