Location

San Diego, California

Presentation Date

29 Mar 2001, 4:00 pm - 6:00 pm

Abstract

In this paper, focusing on the caisson type quay wall, which is a typical gravity type of shore structures, the seismic behavior of the structures was discussed when the liquefaction occurs, by applying the dynamic response analysis and a simplified prediction method which was proposed by the authors. Firstly, a simplified and reasonable method for predicting the seismic behavior of shore structures during earthquakes was proposed. In the proposed analytical method, the structure is replaced by a simplified model, and the ground contacting the structure by subgrade springs. There are two types of subgrade springs employed as elasto-plastic spring and liquefied spring. Secondly, the seismic behavior of shore structures in liquefied areas was evaluated through case study by dynamic response analysis. As the result, it was elucidated that the residual horizontal displacement of structures depends on the maximum horizontal acceleration acting at the center of structures, and the duration of earthquake motion is closely related to the residual horizontal displacement. It is also confirmed that the residual horizontal displacement of irregular seismic wave is 1/3 to 2/3 times smaller than that of regular seismic wave. After then, in order to confirm the applicability of the proposed simplified prediction method, a case study was performed to compare the result of the simplified analysis with that of the dynamic response analysis. As the result, the relationships between the horizontal acceleration at ground surface and the residual horizontal displacement by both analyses without liquefaction showed a similar trend, while those with liquefaction showed different trends, which was due to the difference of evaluating the semi-liquefaction, It was confirmed that the proposed simplified prediction method was applicable to predicting the actual seismic behavior of shore structures with good accuracy by adequately adjusting the reduction ratio of liquefied spring in the semi-liquefaction condition.

Department(s)

Civil, Architectural and Environmental Engineering

Meeting Name

4th International Conference on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics

Publisher

University of Missouri--Rolla

Document Version

Final Version

Rights

© 2001 University of Missouri--Rolla, All rights reserved.

Creative Commons Licensing

Creative Commons License
This work is licensed under a Creative Commons Attribution-Noncommercial-No Derivative Works 4.0 License.

Document Type

Article - Conference proceedings

File Type

text

Language

English

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Mar 26th, 12:00 AM Mar 31st, 12:00 AM

Analytical Evaluation for Seismic Behavior of Shore Structures on Liquefied Area During Earthquakes

San Diego, California

In this paper, focusing on the caisson type quay wall, which is a typical gravity type of shore structures, the seismic behavior of the structures was discussed when the liquefaction occurs, by applying the dynamic response analysis and a simplified prediction method which was proposed by the authors. Firstly, a simplified and reasonable method for predicting the seismic behavior of shore structures during earthquakes was proposed. In the proposed analytical method, the structure is replaced by a simplified model, and the ground contacting the structure by subgrade springs. There are two types of subgrade springs employed as elasto-plastic spring and liquefied spring. Secondly, the seismic behavior of shore structures in liquefied areas was evaluated through case study by dynamic response analysis. As the result, it was elucidated that the residual horizontal displacement of structures depends on the maximum horizontal acceleration acting at the center of structures, and the duration of earthquake motion is closely related to the residual horizontal displacement. It is also confirmed that the residual horizontal displacement of irregular seismic wave is 1/3 to 2/3 times smaller than that of regular seismic wave. After then, in order to confirm the applicability of the proposed simplified prediction method, a case study was performed to compare the result of the simplified analysis with that of the dynamic response analysis. As the result, the relationships between the horizontal acceleration at ground surface and the residual horizontal displacement by both analyses without liquefaction showed a similar trend, while those with liquefaction showed different trends, which was due to the difference of evaluating the semi-liquefaction, It was confirmed that the proposed simplified prediction method was applicable to predicting the actual seismic behavior of shore structures with good accuracy by adequately adjusting the reduction ratio of liquefied spring in the semi-liquefaction condition.