The lateral pressure exerted by expansive soils on retaining walls constructed with expanded polystyrene geofoam blocks (EXRW-EPS), upon water infiltration to saturation, is crucial for designing these structures. In this study, model tests were employed to examine the behavior of EXRW-EPS subjected to water infiltration, with concurrent monitoring of deformation and lateral pressure. The results showed that the compressive deformation of the expanded polystyrene (EPS) geofoam block facilitated swelling deformations of the backfilled expansive soil, effectively mitigating the lateral pressure experienced by the retaining wall. Upon saturation of the backfilled expansive soil, the total lateral force on the wall decreased by approximately 44% by the EPS geofoam block with a density of 12 kg/m. A practical method for predicting the lateral pressure on EXRW-EPS upon water infiltration to saturation was developed based on the relationship between the EPS geofoam block and the backfilled expansive soil. The reliability of this method was corroborated by the model test results. Additionally, the effects of the density and thickness of the EPS geofoam block on the lateral pressure of EXRW-EPS were analyzed using the prediction method.

中文翻译：

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水渗透时膨胀土对膨胀聚苯乙烯土工泡沫块挡土墙侧压力的室内研究与理论分析

当水渗透至饱和时，膨胀土对由膨胀聚苯乙烯土工泡沫块（EXRW-EPS）建造的挡土墙施加的侧向压力对于设计这些结构至关重要。在本研究中，采用模型试验来检验 EXRW-EPS 在水渗透下的行为，同时监测变形和侧压力。结果表明，膨胀聚苯乙烯（EPS）土工泡沫块的压缩变形促进了回填膨胀土的膨胀变形，有效减轻了挡土墙所承受的侧压力。回填膨胀土饱和后，密度为12 kg/m的EPS土工泡沫块使墙体上的总侧向力降低了约44%。基于 EPS 土工泡沫块与回填膨胀土之间的关系，开发了一种预测水渗透至饱和时 EXRW-EPS 侧压力的实用方法。模型试验结果验证了该方法的可靠性。此外，利用预测方法分析了EPS土工泡沫块的密度和厚度对EXRW-EPS侧压力的影响。