ABSTRACT

Assessment of liquefiable soils strength is a challenging task in engineering practice especially when a structure is founded on top of the liquefied soil. While it has been addressed and studied in the literature, the lack of practically feasible approaches to calculate the bearing capacity of soil in such a condition is tangible. In this study, simple analytical equations have been proposed to calculate the bearing capacity of liquefiable soils under shallow foundations. The equations have been developed for two cases, separated based on the thickness of liquefiable soils and width of foundation, each of which acting with different mechanisms. The proposed approach was evaluated versus field observations from the 1964 Niigata, the 1990 Luzon, and the 1999 Adapazari earthquakes, in addition to an assessment against numerical simulations. It was shown that the methodology is capable of estimating the bearing capacity of liquefiable soils under shallow foundations. The obtained results reveal that decreasing the thickness of the liquefiable layer as well as increasing foundation width leads to a higher bearing capacity. Finally, an easy to use design charts and simple equations have been derived for use in engineering practice.

摘要

液化土强度的评估在工程实践中是一项具有挑战性的任务，尤其是在液化土上建立结构时。虽然在文献中已经对其进行了讨论和研究，但缺乏实际可行的方法来计算这种条件下土壤的承载力是有形的。在这项研究中，已经提出了简单的解析方程来计算浅地基下液化土的承载力。方程已针对两种情况开发，分别基于可液化土壤的厚度和地基的宽度，每种情况都以不同的机制起作用。除了针对数值模拟的评估之外，还针对 1964 年新泻、1990 年吕宋岛和 1999 年阿达帕扎里地震的现场观测对所提出的方法进行了评估。结果表明，该方法能够估算浅地基下液化土的承载能力。所得结果表明，减小液化层厚度以及增加地基宽度会导致更高的承载力。最后，导出了一个易于使用的设计图表和简单的方程，用于工程实践。