作　　者： (何杰）; (高建喜）; (孟森松）; (王忍）;

机构地区： 湖南工业大学土木工程学院,湖南株洲412007

出　　处： 《湖南工业大学学报》 2017年第1期35-40,共6页

摘　　要： 通过模型试验研究了循环荷载作用下土工格栅、土工格室及纯碎石垫层在软土地基上的承载特性;分析不同工况下沉降、桩身应变及桩土应力比随循环次数、峰值荷载的变化规律。研究结果表明:在动载条件下,加筋碎石垫层能有效地限制垫层的位移,显著减小复合地基的累计沉降;加筋后的碎石垫层强度和刚度均得到增强,能有效调节桩-土应力分布,改善碎石垫层的受力特性,大幅度提高桩-土应力比,有效减小桩身应变;同等条件下,土工格室碎石垫层对于减小桩顶沉降、提高桩-土应力比和降低桩身应变的性能略优于土工格栅碎石垫层,并随着循环峰值荷载增加,两者的作用效果更好。 Based on a model testing,a research has been conducted on the load-bearing characteristics of geogrids,geocells and pure gravel cushion on the soft soil foundation under cyclic loading.An analysis has been made of the change regulation of the settlement,the strain of pile and the stress ratio of pile and soil along with cycle times and peak load under different working conditions.The research results show that under the condition of a dynamic loading,the reinforced gravel cushion can effectively limit the displacement of the cushion,and significantly reduce the cumulative settlement of the composite foundation.The strength and stiffness of the reinforced gravel cushion are enhanced,which helps to effectively regulate the distribution of pile-soil stress,improve the stress characteristics of the gravel cushion,and the stress ratio of pile and soil as well,and effectively reduce the strain of the pile.Under the same conditions,the performance of the geocell gravel cushion is slightly better than that of the geogrid gravel cushion in reducing the settlement of pile top,improving the stress ratio of pile and soil and reducing the strain of pile.Meanwhile,with the increase of the cyclic loading,both exhibits much better performance than before.

关 键 词： 软土地基 土工格栅 土工格室 桩 土应力比 循环荷载