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针对有砟轨道加筋路堤计算分析中难以考虑土工格室对碎石填料嵌锁及摩擦作用的现状,在大比尺直剪试验基础上建立考虑填料–格室相互作用的三维计算模型。通过室内模型试验验证该计算的可靠度和优越性,进而系统地分析有/无加筋情况下,填料强度、土工格室刚度及地基压缩性等参数对路堤力学响应的影响。结果表明:土工格室的嵌锁作用使得加筋对路堤响应的影响在其布设层发挥程度更大,该影响通过填料与格室及填料内的摩擦作用向周围传递且不断衰减;填料强度较低或地基较软时能加强土工格室对路堤响应的影响,对于填料内摩擦角为20°和地基变形模量为5 MPa的工况而言,加筋后基床侧向位移峰值分别降低60%和72%,应力峰值亦显著降低且分布区域明显扩大;土工格室弹性模量为0.2~2.5 GPa时,路堤力学响应受其影响较大。
In view of the current situation that the geocell is not suitable for the interlocking and rubbing effect of gravel packing in the calculation and analysis of the reinforced embankment with ballasted orbit, a three-dimensional computational model considering the interaction of filler and lattice is established on the basis of the large-scale direct shear test. Through the indoor model test, the reliability and superiority of the calculation are validated, and the influence of the parameters such as filler strength, geocell stiffness and foundation compressibility on the mechanical response of embankment is systematically analyzed. The results show that the effect of geogrid locking on the embankment is more affected by the embankment response. The influence of embedment on the embankment is greater than that of the embankment. The influence is transmitted to the surrounding by the friction effect between the filler and the cell and the filler. The effect of geocell on the embankment response can be strengthened by low or soft foundation. For the working condition with internal friction angle of 20 ° and deformation modulus of 5 MPa, the peak value of lateral displacement of reinforced bed decreases 60% and 72% respectively. The stress peak also decreased significantly and the distribution area expanded obviously. When the elastic modulus of geocell was between 0.2 and 2.5 GPa, the mechanical response of embankment was greatly affected.