浙赣线提速路基基床承载力评估及加固措施

Studying the Bearing Capacity and Treatment Methed of Subgrade for Speed-raising Subgrade Reconstruction of Zhejiang-Jiangxi Railway Line

首先根据路基不同深度处的动应力衰减规律和浙赣线既有路基状况，提出了路床土强度控制条件为：基床表层0—0．3m和0．3～0．6m应分别满足160kPa和110kPa的承载力要求，并采用轻型动力触探（N10）对基床土承载力进行了检测和评估，结果表明，不满足基床土强度控制条件地段约占非改线全段的20％。其次，根据基床土承载力检测结果和基床土填料情况，提出了土工布封闭结合土工格室、换填的加固方法，而换填厚度取决于承载力大小和选取用的格室高度，为浙赣线200km／h提速改造提供了依据。

Based on the dynamic stress attenuation nile at different depth and the existing subgrade quality status in Zhe- Jiang-Jiangxi Railway Line, the subgrade strength control condition is suggested. The bearing capacity of subgrade soil should separately satisfy 160 kPa and 110 kPa at the depth of 0 -0.3 m and the depth of 0.3 -0.6 m. The bearing capacity of subgrade soil is studied by using light sounding test blow court （ N10 ）, The result shows that the percent of dissatisfactory subgrade strength control condition is about 20% on the whole unchanged line. According to the bearing capacity and filled soil type of subgrade, the treatment method that geotextile blocks out geocell and ground soil is replaced is put forward. The soil replacement thickness is decided by the bearing capacity and the geocell height. This will provide a basis for speed-raising subgrade reconstruction of ZheJiang-Jiangxi Railway Line at 200 km/h.