Abstract In design, internal stability of EPS lightweight fills are provided either by applying load distributing mechanisms (thick pavements or concrete slabs) or using more strong lightweight material through denser EPS geofoam blocks. However, unit weight of the EPS geofoam is a limited parameter. As an attempt to improve the mechanical properties of EPS geofoam, geocell-geofoam composite (GGC) is introduced in this study. Geocell mattresses were infilled with solidified geofoam beads in the factory to fabricate GGC. The EPS geofoam and GGC samples were tested using a large-scale shear test apparatus of size measuring 1 m3. Results indicate that inclusion of the geocell leads to a considerable increase in the shear strength and a great decline in the compressibility of the geofoam. In comparison with EPS blocks, up to 72% rise in the shear strength and 67% decline in the vertical displacement were observed in GGC samples at the normal stress of 35 kPa. In addition, incorporation of the geocell was found to change the resisting mechanism of the EPS geofoam from cohesive to cohesive-frictional. While there was only 4.5% decline in the cohesion, the internal friction angle of the tested geofoam increased six-fold due to the involvement of the geocell.

中文翻译：

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土工格室-土工泡沫复合材料的剪切行为

摘要 在设计中，EPS 轻质填料的内部稳定性通过应用载荷分配机制（厚路面或混凝土板）或通过更密集的 EPS 土工泡沫块使用更坚固的轻质材料来提供。然而，EPS 土工泡沫的单位重量是一个有限的参数。为了提高EPS土工泡沫的力学性能，本研究引入了土工格室-土工泡沫复合材料（GGC）。Geocell 床垫在工厂中填充固化的土工泡沫珠以制造 GGC。EPS 土工泡沫和 GGC 样品使用尺寸为 1 立方米的大型剪切试验装置进行测试。结果表明，土工格室的加入导致剪切强度的显着增加和土工泡沫压缩性的大幅下降。与EPS块相比，在 35 kPa 的法向应力下，在 GGC 样品中观察到剪切强度增加了 72%，垂直位移减少了 67%。此外，发现土工格室的加入将 EPS 土工泡沫的抵抗机制从内聚到内聚摩擦。虽然内聚力仅下降 4.5%，但由于土工格室的参与，测试的土工泡沫的内摩擦角增加了 6 倍。