组合支挡作用下桩板墙与悬臂式挡墙协同作用分析研究

Analysis and Research on the Synergy of Pile Sheet Wall and Cantilever Retaining Wall under the Action of Combined Retaining Wall

当路基帮宽受地形条件和建设用地等限制而无法实施时,在路基边坡处增设桩板墙等支挡结构,与既有结构相结合,形成新型组合支挡结构,可以很好地实现路基的帮宽,既不占用新的建设用地,又能够充分利用既有支挡结构。由于组合支挡结构的复杂性,设计了相似比为1:25的路基边坡模型,通过室内模型试验,研究了竖向分级荷载作用下组合支挡结构的受力状态和变形特点。研究结果表明:64 kPa等效荷载作用下,桩身与悬臂墙位移变形比为7:1,最大拉应力和最大弯矩分担比分别为1.67:1和3.77:1,各级荷载下土压力的分担比均接近2:1,既有悬臂墙支挡作用明显,仍有较大的利用价值。

When the subgrade widening cannot be implemented due to the limitations of topographic conditions and construction land, pile sheet wall and other retaining structures shall be added at the subgrade slope to form a new combined retaining structure combined with the existing structure, which can well realize the subgrade widening, not only do not occupy new construction land, but also make full use of the existing retaining structure. Due to the complexity of composite retaining structure, a subgrade slope model with similarity ratio of 1:25 is designed. Through indoor model test, the stress state and deformation characteristics of composite retaining structure under vertical graded load are studied. The results show that under the equivalent load of 64 kpa, the displacement deformation ratio of pile body and cantilever wall is 7:1, the sharing ratio of maximum tensile stress and maximum bending moment is 1.67:1 and 3.77:1 respectively, and the sharing ratio of earth pressure under various loads is close to 2:1. The existing cantilever wall has obvious retaining effect and still has great utilization value.