中文摘要：

通过现场试验研究了刚柔同轴组合桩（简称CRFC桩）的桩土荷载分担比、地表沉降、深层水平位移等随路堤荷载和时间的变化规律,并与排水固结法和水泥搅拌桩进行了对比。研究结果表明：（1）路堤填筑初期荷载主要由桩间土承担,且填筑期内桩间土压力逐渐向CRFC桩转移,然而路堤荷载较小时,荷载转移不明显;（2）CRFC桩施工引起的超孔隙水压力消散较快,相比较而言复合地基中CRFC桩施工过程及路基填筑过程中上部孔隙水压力变化较大,下部变化不明显;（3）随着路堤荷载的增加,路堤侧向变形速率减低,且侧向变形在监测后期有一定的恢复变形;（4）与其他处理方式相比,CRFC桩复合地基的总沉降量和工后沉降量小,且沉降收敛快,沉降主要发生在路堤填筑期。

英文摘要：

According to the field tests, the variations of pile-soil load share ratio, surface settle- ment, and deep lateral displacement of coaxial rigid-flexible compound pile （CRFC pile） with em- bankment loading and time were investigated, and the comparison was made between drainage consolidation method and treatment method by building cement mixing piles. The following con- clusions can be obtained. （1） The loading in the early stage of embankment filling is mainly sup- ported by the soil between piles, and the soil pressures between piles are gradually transferred to the CRFC pile during embankment filling; however, the loading transfer is not obvious when the embankment loading is relatively small; （2） the excess pore pressure caused by the CRFC pile in- stallation dissipates faster; while the excess pore pressures during the CRFC pile installation and embankment filling in the compound foundation change larger in the upper than those in the lower part （3） the lateral deformation rate of embankment decreases with the increase of embankment loading, and the lateral deformation has certain recovery in the later stage of monitoring; （4） comparing with other treatment methods, the total settlement and post-construction settlement of CRFC pile composite foundation are smaller, and the settlement convergence is faster; in addi- tion, the subsidence mainly occurs during the filling period.