用土工织物散体桩加固季节冻土地区沼泽软土地基

Reinforcing the Marsh Wetland Foundation in Seasonal Frozen Area with Geotextiles Repose of Pile

以同抚公路青龙山农场支线试验路段为对象,研究土工织物散体桩加固季节冻土地区沼泽软土地基的应用效果。采用现场钻探得到试验路段沼泽软土的分布厚度,并对在不同深度取得土样进行室内物理力学试验;采用动力触探仪测试土工织物散体桩处理前后的试验路段地基土的强度变化。结果表明：在散体桩施工后,动力触探锥头阻力由0.5~5.0 MPa提升到5~10 MPa,复合地基桩间土的软土地基强度有了明显提升。在试验路段选择2个监测断面,在每个断面两侧路肩、中线位置设置沉降标,监测土工织物散体桩加固处理和路基填筑前后测点地基沉降量。结果表明：绝大部分沉降量发生在土工织物散体桩施工过程中和路基填土施工过程中,在路基填筑施工完成,并经历一个冻融循环后,地基沉降量明显减小,说明试验路段所采用的土工织物散体桩加固处理地基措施效果良好。

Taking Qinglongshan Farm subcircuit regional test section of Tongfu Road as the research object,we studied the application effect of geotextiles medium pile reinforce the foundation in seasonal frozen soil area swampy ground. Using the insitu drilling exploration and dynamic sounding survey,we obtained area distribution of soft soil thickness swamp,and did indoor physical and mechanical test of soil sample on every depth. We used dynamic sounding survey to test the road foundation soil strength changes before and after the geotextiles medium pile treatment. After the repose of pile construction,the dynamic cone head resistance was raised from 0.5-5 MPa to 5-10 MPa,and the strength of soil in the soft layer between piles in composite foundation was improved significantly. We chose two monitoring sections on the road,set monitoring piles on the each section in settlement of subgrade center line and on both sides of the road shoulder to monitor the monitoring piles foundation settlement before and after reinforcement and roadbed filling. The foundation settlement occurred in geotextiles repose of subgrade filling pile construction process and construction process for the most part,the settlement was small after roadbed filling completion,and the adoption of geotextiles repose of the pile foundation reinforcement treatment effect was good by the embankment test section.