Abstract Plate loading tests were conducted to investigate the effect of a bottom boundary condition on the pressure-settlement behavior of a footing on sand with a limited thickness involving geosynthetics. Seven boundary materials including geosynthetics were used to create different boundary conditions at the bottom of the sand. Interface direct shear tests were conducted first to determine the interface friction angles between these boundary materials and sand, followed by plate loading tests to determine their pressure-settlement curves. Test results show that the sand with a limited thickness by a rigid bottom boundary had a higher bearing capacity than that with a larger thickness. The ultimate bearing capacity of the footing on the sand with a limited thickness generally increased with the increase of the interface friction angle. Geosynthetics provided better lateral restraint than other materials. An equation was developed to describe the relationship of the bearing capacity ratio of the sand with a limited thickness to that with a large thickness versus the soil thickness and the interface interaction coefficient. The effect of the boundary material on the back-calculated modulus of the sand was also evaluated.

中文翻译：

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土工合成材料有限厚度地基土压力沉降行为边界效应的室内研究

摘要 进行了板加载试验，以研究底部边界条件对土工合成材料有限厚度沙子上基础的压力沉降行为的影响。包括土工合成材料在内的七种边界材料被用来在沙子底部创造不同的边界条件。首先进行界面直剪试验以确定这些边界材料与沙子之间的界面摩擦角，然后进行板加载试验以确定它们的压力-沉降曲线。试验结果表明，刚性底部边界限制厚度的砂比具有较大厚度的砂具有更高的承载力。有限厚度沙子上的基脚的极限承载力一般随着界面摩擦角的增加而增加。土工合成材料比其他材料提供更好的横向约束。建立了一个方程来描述有限厚度砂与大厚度砂的承载力比与土壤厚度和界面相互作用系数的关系。还评估了边界材料对砂的反算模量的影响。