Model tests and numerical analyses of stepped reinforced retaining wall were performed to investigate the effects of rheology of backfill and creep of geogrids on the long-term performance of the structure.The geogrid...Model tests and numerical analyses of stepped reinforced retaining wall were performed to investigate the effects of rheology of backfill and creep of geogrids on the long-term performance of the structure.The geogrid tensions,soil pressures,wall deformations and foundation pressure were measured during model construction and loading.A visco-elasto-plastic model and an empirical nonlinear visco-elastic model were utilized to simulate the stresses and deformations of geogrid-reinforced earth-retaining wall under long-term loads.By comparing test data with numerical results,it is shown that the foundation pressure distribution is nonlinear,and the lateral constraint of geogrids for backfill can cause a redistribution of foundation pressure.The curve of soil pressure is outside convex at each step initially,and it is close to the distribution for the case of vertical wall subsequently.The variation trend of geogrid tensions at different heights is obtained.Moreover,the failure mechanism and development mode of potential slip surface in retaining wall are proposed.展开更多
The collapsibility of loess, which can be effectively eliminated by the dynamic compaction, does great harm to the safety of constructions. The effect of the dynamic compaction is evaluated through the contrast and an...The collapsibility of loess, which can be effectively eliminated by the dynamic compaction, does great harm to the safety of constructions. The effect of the dynamic compaction is evaluated through the contrast and analysis of the physical and mechanical properties of the collapsible loess before and after dynamic compacting. The compacting effect can be divided into three phases along the depth, and the most effective improved depth is from 3 to 8 m.展开更多
基金Supported by National Natural Science Foundation of China (No. 50678032 and No. 90715042)Key Project of Ministry of Education of China (No. 210176)
文摘Model tests and numerical analyses of stepped reinforced retaining wall were performed to investigate the effects of rheology of backfill and creep of geogrids on the long-term performance of the structure.The geogrid tensions,soil pressures,wall deformations and foundation pressure were measured during model construction and loading.A visco-elasto-plastic model and an empirical nonlinear visco-elastic model were utilized to simulate the stresses and deformations of geogrid-reinforced earth-retaining wall under long-term loads.By comparing test data with numerical results,it is shown that the foundation pressure distribution is nonlinear,and the lateral constraint of geogrids for backfill can cause a redistribution of foundation pressure.The curve of soil pressure is outside convex at each step initially,and it is close to the distribution for the case of vertical wall subsequently.The variation trend of geogrid tensions at different heights is obtained.Moreover,the failure mechanism and development mode of potential slip surface in retaining wall are proposed.
基金Acknowledgement The authors of this paper thank the financial support from National Natural Science Foundation of China through project No.50478096.
文摘The collapsibility of loess, which can be effectively eliminated by the dynamic compaction, does great harm to the safety of constructions. The effect of the dynamic compaction is evaluated through the contrast and analysis of the physical and mechanical properties of the collapsible loess before and after dynamic compacting. The compacting effect can be divided into three phases along the depth, and the most effective improved depth is from 3 to 8 m.
