加筋垫层对桩-网复合地基桩土应力比影响试验

摘要

For tensioned membrane effect of the reinforcing material,reinforced cushion can increase the pile beating load capacity,with a direct impact on arching effect of the upper embankment.Early studies show that reinforced cushion is very crucial in the adjustment of pile-soil stress.By better research in the impact of reinforced cushion on pile-soil stress ratio in pile-net composite foundation under the embankment load,model comparison test is designed,and the soil pressure of cushion bottom and the top surface are continuous observed.The results show that reinforced cushion contributes to improve the piles-soil stress ratio of pile-net composite foundation,especially in the embankment initial stage,and can further weaken the arch effect in the upper embankment.Therefore,reinforced cushion can improve the piles-soil stress ratio of pile-net composite foundation,and can weaken the arch effect in the upper embankment.%由于加筋材料的拉膜效应,加筋垫层不仅加大了桩体承担荷载的能力,对上部路堤填土中的拱效应也有直接的影响.为了较好地研究加筋垫层对路堤荷载下桩-网复合地基桩土应力比的影响,设计了模型对比试验,分别对垫层底面和顶面的土压力进行了连续观测.结果表明,加筋垫层有助于桩-网复合地基桩土应力比的提高,尤其在填筑初期桩土应力比增长较快,并能进一步削弱上部路堤填土中的拱效应.因此加筋垫层可以提高桩-网复合地基桩的应力比,并且可以削弱上部路堤的拱效应.