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目前对土工格室加筋路堤研究主要集中在静载条件下,动载条件下研究的比较少。为研究分级循环荷载下土工格室加筋路堤的力学性能,采用USTX-2000的动力加载装置进行加载,对土工格室加筋路堤在不同加筋层数、格室高度、格室焊距等工况下进行一系列模型试验。对分级循环荷载下路堤的竖向变形和坡面法向变形进行研究,并与固定振幅循环荷载及静载作用下的路堤进行对比分析,研究不同加载方案路堤力学性能的差异性。试验结果表明,土工格室加筋能显著提高路堤承受分级循环荷载的能力和减小竖向累积沉降量,在加筋间距一定的情况下,两层及以上加筋效果比单层加筋效果更显著,格室高度增大和格室焊距减小均可不同程度提高路堤承受分级循环荷载能力并减小竖向累积沉降量;加筋可减小路堤分级循环荷载下的坡面法向变形,格室高度增大和格室焊距减小在分级循环荷载幅值相同时均能减小坡顶和坡中处的法向累积变形;分级循环荷载作用下,当振次≥8 000或幅值≥80 k Pa时,路堤竖向累积沉降量超过固定振幅循环荷载,当振次≥9 000或振幅≥90 k Pa时,路堤坡顶法向累积变形超过固定振幅循环荷载;分级循环荷载作用下,路堤竖向和坡面法向累积变形均大于静载,加筋可有效减小分级循环荷载和静载作用下坡面法向累积变形差。
At present, the researches on geogrid-reinforced embankment mainly focus on static loading conditions, and there are few studies under dynamic loading conditions. In order to study the mechanical performance of geocell-reinforced embankment under cyclic load, the dynamic loading device of USTX-2000 was used to load the geocell reinforced embankment in different reinforced layers, cell height, A series of model tests were carried out under operating conditions. The vertical deformation of the embankment and the normal deformation of the slope under cyclic loading are studied, and compared with the embankment under constant cyclic loading and static loading, the differences of mechanical properties of embankments under different loading schemes are studied. The test results show that geogrid reinforcement can significantly improve the ability of embankments to withstand cyclic loading and reduce the cumulative vertical settlement. Under the condition of certain reinforcement spacing, the reinforcing effect of two or more layers is better than that of single-layer reinforcement More significant, the increase of the cell height and the decrease of the welding space of the cell room can all improve the cyclic load capacity of the embankment to a certain extent and reduce the vertical cumulative settlement; the reinforcement can reduce the normal deformation of the slope surface under the graded cyclic loading of the embankment , The height of cell room increases and the welding space of cell decreases. When the magnitude of cyclic loading is the same, the normal cumulative deformation at the top and the slope can be reduced. When the cyclic loading is greater than or equal to 8000 When the value is ≥80 kPa, the cumulative vertical settlement of the embankment exceeds the cyclic loading of fixed amplitude. When the vibration amplitude is more than 9000 or the amplitude is greater than or equal to 90 kPa, the normal cumulative deformation of the embankment slope exceeds the fixed amplitude cyclic loading. , The cumulative normal deformation of vertical embankment and slope is larger than static load. Reinforcing can effectively reduce the cumulative normal deformation of slope under cyclic loading and static loading.