带桩帽桩网加固路堤的模型试验及分析比较

ANALYSIS AND COMPARISON OF MODEL TEST REINFORCED EMBANKMENT BY PILE NET WITH PILE CAP

采用三维模型试验,考虑路堤高度、桩帽宽度、桩净间距、工后固结沉降、桩间土压缩模量、水平加筋体等影响因素,对桩网结构加固路堤的沉降变形和荷载传递规律进行系统的研究,得到一些有益的结论,并且将试验的部分结果与理论解析解进行比较,结果发现:对于三维空间土拱,BS 8006法、改进的太沙基法、Hewlett和Randolph法所计算的结果与试验结果较为吻合,并且随着桩帽尺寸的增加,它们之间的吻合程度越来越好。而改进的Guido法和Carlsson法计算的结果与试验结果差异较大。该研究成果可为桩网结构加固路堤设计提供有益的参考。

The settlement deformation characteristic and load transfer mechanism of pile-net reinforced embankment are studied through the 3D model test, considering the factors of embankment height, width and clear spacing of pile cap, residual consolidation settlement, compression modulus of soil between piles and geotextile. Some useful test conclusions are obtained. The results of model tests are compared with the calculated results of analytical methods. The results show that for 3D situation, the results obtained from BS 8006＇s , adapted Terzaghi＇s and Hewlett＇s methods are in fair agreement with the results of model tests. And the calculated results of analytical methods are well agreed with the results of model tests with the increasing of width of pile cap.However, the adapted Guido＇ s and Carlsson＇ s methods overestimated the efficiency. The conclusions may be a valuable reference for the design of pile net reinforced embankment.