中文摘要：

为研究桩承式加筋路堤填土中竖向应力分布和土拱效应临界高度的变化规律,依托塑料套管现浇混凝土桩（TC桩）承式路堤现场试验,在填筑预压期对桩帽、桩间土及不同填土高度处土压力进行全过程监测,分析了路堤填筑及预压过程中桩土间的荷载传递规律,同时结合土拱设计高度计算方法,研究填土中竖向应力分布和土拱效应临界高度的变化规律,对多种土拱形式的假定进行了现场试验验证分析,并基于试验结果,开展了路堤土拱形成的参数讨论。研究结果表明：填土高度约达到0.5倍桩间距时,桩帽上压力实测值大于该处路堤荷载,且桩土应力比大于1,表明路堤载荷开始从桩间土向桩体转移,路堤内土拱初步形成;填土高度约达到0.9倍桩间距后,后续填土对桩间土压力变化影响较小,说明路堤已形成完整稳定的土拱;观测到的土拱等沉面的高度为1.2-1.5m,大于德国EBGEO规程计算值,小于英国BS 8006规范计算值;与滑动面为沿桩顶轮廓线向上的假定与应力扩散理论相比,路堤中竖向土压力分布趋势与圆形土拱假定计算结果相符,但试验所得土压力测量值仅为理论计算值的50%和30%。因桩承式加筋路堤中桩间土压力随其距桩的位置不同会有明显不同,故建议采用桩土应力比联合桩帽上土压力大小综合判定桩承式加筋路堤的土拱形成。

英文摘要：

In order to research the vertical stress distribution in filling and critical height of soil arch effect, the stress of pile cap, soil between piles and fill at different height were monitored and recorded, on the basis of field test on plastic tube cast-in-place concrete pile （TC pile）-supported embankment, the load transfer during the periods of embankment filling and preloading was analyzed. Meanwhile, vertical stress distribution in filling and critical height of soil arch effect was studied, assumptions about the soil arch was compared with the test results. Based on the experimental results, parameters of embankment soil arch were also discussed. The results show that the pile-soil stress ratio is more than 1 and the measured values of earth pressures on pile cap is bigger than the embankment load when the filling height of embankment approaches to 0.5 times of pile spacing, which indicates that embankment load begins to transfer from soils to piles and soil arching is initially formed. When height of the embankment is close to 0.9 times of pile spacing, the corresponding earth pressures in soils change little, which reveals that the complete and stable soil arching has been produced, the change range of soil arching root be carried as the reason. The measured height of equal settlement plane is between the calculated values of EBGEO and BS 8006. The monitoring of earth pressures in embankment demonstrates that soil arching is in a shape of semicircular. However, the measured values of earth pressures on pile cap and cushion are 50% and 30% of the calculated results from semicircular soil arching theory. Pile-soil stress ratio with the value of earth pressure on pile is suggested to judge the formation of soil arch in pile-supported reinforced embankment. 2 tabs, 7 figs, 22 refs.