桩承式加筋路堤土拱及格栅受力模型试验研究

Experimental Study on Behaviors of Soil Arch and Geogrid in a Pile-supported Reinforced Embankment

介绍了桩承式加筋路堤足尺模型实验装置,该实验装置利用PVC材料水袋模拟桩间软土,从而在一定程度上能够控制桩土差异沉降。路堤填筑过程中测试了路堤内部土压力以及格栅拉力,并且重点分析了桩帽和桩间不同位置处土压力以及格栅拉力随填筑高度的变化规律。实验结果表明,路堤在填筑过程中发生了明显的土拱效应,路堤填筑完成后桩土应力比约为8.46,土拱高度约为1.125倍桩间净距;单向土工格栅能够进一步将桩间上方土压力传递到桩顶上方;随着路堤填筑高度的增加,格栅拉力增长并不大,路堤横向滑移引起的格栅拉力可以忽略不计。

This paper describes a full-scale experiment installation of pile-supported reinforced embankment. A water-bag made of PVC material was used to model the soil surrounding the pile caps and it is possible to control pilesoil differential settlement. The earth pressure and geosynthetic tensile force were measured during the construction of the embankment. The relationship between the height of embankment and the earth pressure or the geosynthetic tensile force at different positions of pile caps and subsoil is analyzed in detail. The results of the experiment show that an arching effect was formed evidently during the construction of embankment. The ratio of pile-soil pressure is about8. 46 and the height of soil arch is 1. 125 times of pure distance between pile caps. The embedded geogrid could transfer soil pressure to pile caps in further. The geosynthetic tensile force had a rather small increment during the construction. So the geosynthetic tensile force induced by the spreading force could be ignored.