无面板加筋土路堤变形特征及破坏机理研究

以十房高速公路无面板加筋土路堤为研究对象，结合现场实测数据，采用有限元程序对该类型加筋土路堤的变形破坏特征和破坏模式进行计算分析。在此基础上，对加筋土路堤的加筋刚度、加筋间距进行参数分析。主要结论如下：①加筋土路堤底层填土由于圬工挡墙后部填土厚度较大而出现不均匀沉降，且不同刚度的筋材对其影响不大，施工时需保证圬工挡墙后部填土的压实度。②各层加筋体最大应变值均分布在靠近路堤坡面处，其轴力最大值位于加筋土路堤中下部。③破坏模式为内部破坏，表现为筋材拉断，破坏面靠近加筋土路堤坡面处；圬工挡墙的结构强度和基础稳定性对整个加筋土路堤的稳定性具有重要作用。④随着加筋体轴向刚度的增加和加筋间距的减小，双向位移逐渐减小，而安全系数均相应增大，但加筋体轴向刚度增加到一定程度时，其对加筋土路堤的变形稳定特征影响减弱。研究成果对山区加筋土路堤的设计计算和施工具有一定的理论和借鉴意义。

STUDY ON DEFORMATION AND FAILURE MECHANISM OF NO-PANEL REINFORCED EMBANKMENT

Taking the reinforced embankment of Shifang highway as research object and combing with on-site monitoring data, the deformation and failure characteristics of the reinforced embankment are studied using the elastic-plastic finite element program. On this basis, parametric analysis is carried out on the reinforcement stiffness, reinforcement spacing. The main results show that: ① due to the thick backfill behind the masonry retaining wall, there is an uneven settlement at the bottom of the reinforced embankment, and the reinforcement stiffiness almost has no effect on it, therefore, the compaction degree of the backfill behind the masonry wall should be guaranteed.② maximum strains at all levels of the reinforcement are distributed in the near embankment slope, and the maximum axial force is located in the lower part of the reinforced embankment.③ the failure mode of the reinforced embankment belongs to internal failure, i.e.the reinforcement is pulled off. The failure surface is located near the reinforced embankment slope; the structural strength and stability of masonry retaining wall foundation has an important role on the whole stability of the reinforced embankment.④ with the increasing of the axial stiffness and the decreasing of the reinforcement spacing, the bi-directional displacements are decreased and the safety factor are increased accordingly. However, when the axial stiffness of the reinforced body reaches a certain extent, its influence on the deformation characteristics of the reinforced embankment is greatly weakened. The results have a certain theoretical and reference meaning on the design calculation and construction of the mountaineous reinforced embankment.