Controlling settlement and earth pressure behind retaining wall in soft soil area are ongoing practical problems for the construction and operation of highway, which are mainly caused by the poor nature of soft soil. To reduce the pushing force on retaining wall and subgrade settlement, the authors propose the use of lightweight foamed concrete as subgrade filler behind the buttressed earth-retaining wall. However, the mechanical properties and deformation behavior of the buttressed earth-retaining wall remain unknown when lightweight foamed concrete is used as a backfill behind the wall. To solve this problem, a scale model of the subgrade filled with lightweight foamed concrete behind the buttressed earth-retaining wall is established to determine its stress and deformation characteristics under different factors. Lateral earth pressures and wall displacements at different elevations of the retaining wall model were monitored during the tests. Then, a series of orthogonal experiments are conducted to analyse and compare the effects of overload, density, and replacement thickness of lightweight foamed concrete on the earth pressure and displacement of this retaining wall. The results show that the size of earth pressures at the same position of retaining wall is affected by overload, density, and replacement thickness of lightweight foamed concrete, but its change of distribution form is only related to the replacement thickness of this backfill. Additionally, the primary-secondary relations of different factors’ influence extent on the forces and deformation of the buttressed earth-retaining wall filled with lightweight foamed concrete as backfill are obtained by using range analysis method.

中文翻译：

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轻质泡沫混凝土回填材料对支墩挡土墙应力变形的影响

控制软土地区挡土墙后的沉降和土压力是公路建设和运营中持续存在的实际问题，主要是由于软土性质差造成的。为了减少挡土墙的推力和路基沉降，作者建议使用轻质泡沫混凝土作为支撑挡土墙后面的路基填料。然而，当轻质泡沫混凝土被用作墙后的回填物时，支撑式挡土墙的力学性能和变形行为仍然未知。为解决这一问题，建立了支护挡土墙后填充轻质泡沫混凝土路基的比例模型，以确定其在不同因素下的应力和变形特征。在测试过程中监测了挡土墙模型不同高度的侧向土压力和墙体位移。然后，通过一系列正交试验，分析比较了轻质泡沫混凝土超载、密度、置换厚度对挡土墙土压力和位移的影响。结果表明，挡土墙同一位置的土压力大小受轻质泡沫混凝土的超载、密度和置换厚度的影响，但其分布形式的变化仅与该回填土的置换厚度有关。此外，