《Journal of Geotechnical and Geoenvironmental Engineering》杂志刊登“液化砂土上建筑物响应的数值模拟”

作者：Shideh Dashti; and Jonathan D. Bray

刊物：《Journal of Geotechnical and Geoenvironmental Engineering》，2013年8月，139卷第8期，1235–1249页

关键词：离心机；液化；减缓；数值分析；沉降；浅基础；土-结构相互作用

摘要：抗震结构的有效设计和液化减缓技术需要对液化的发展和结果有更深入的了解。本文采用液化砂土上具有浅基础结构物的离心试验结果对一种现有的数值工具的预测能力进行评估。在FLAC-2D中执行与UBCSAND模型完全耦合的数值模拟，对于一个大多介于0.7到1.8之间的缩尺输入动作，合理地记录试验中测得的建筑物沉降。土体模型记录了所有的位移分量的分布和局部排水循环荷载作用下的局部体应变。对于较低的地震能量发展速率，此时土体软化和建筑物位移的范围被过高的估计了，因数高达4，该模型主要的局限性变得十分明显。为提供液化砂土上建筑物响应指南和液化补救策略的性能，最后结合了最近一些工程案例的观测结果、试验结果以及数值分析对其进行了深入的探讨。

Numerical Simulation of Building Response on Liquefiable Sand

Authors: Shideh Dashti; and Jonathan D. Bray

Journal: Journal of Geotechnical and Geoenvironmental Engineering, Volume 139, Issue 8(August 2013), 1235–1249

Key words: Centrifuge, Liquefaction, Mitigation, Numerical analysis, Settlement, Shallow foundation, Soil-structure interaction

Abstract: The effective design of earthquake-resistant structures and liquefaction mitigation techniques requires an improved understanding of the development and consequences of liquefaction. In this paper, the results from centrifuge experiments of structures with shallow foundations on liquefiable sand were used to evaluate the predictive capabilities of a state-of-the-practice numerical tool. Fully-coupled numerical simulations with the UBCSAND model implemented in FLAC-2D captured building settlements measured in these experiments reasonably well for one scaled input motion, mostly within factors of 0.7 and 1.8. The soil model captured the overall contribution of deviator displacement mechanisms and localized volumetric strains during partially drained cyclic loading. The primary limitation of the model became evident for slower rates of earthquake energy buildup, when the extent of soil softening and building displacement was overestimated by up to a factor of 4. The observations from recent case histories, the results of the experiments, and the insights gained from the numerical analyses are combined to provide guidance on the evaluation of building response on liquefiable sand and the performance of liquefaction remediation strategies.

原文链接：http://ascelibrary.org/doi/abs/10.1061/%28ASCE%29GT.1943-5606.0000853