管桩水泥土复合基桩抗拔荷载传递规律试验研究

Experimental study of uplift load transfer mechanism of composite piles of jet-mixing cement and PHC pile

为研究管桩水泥土复合基桩在竖向上拔荷载作用下桩身荷载传递规律,结合现场荷载试验及桩身光纤光栅应力测试,研究各级荷载下桩身轴力、侧摩阻力及变形量的变化特征。经分析得出:管桩水泥土复合桩荷载-上拔量(P-S)曲线变化较缓;管桩主要承担竖向抗拔荷载,在端部上拔荷载作用下,桩身轴力在桩端最大,沿桩身向上逐渐减小,管桩主要依靠桩身下部和中部承担上拔荷载。

The up lift static load and fiber bragg grating stress tests were conducted in construction site to study the uplift load transfer mechanism of the composite pile.By the research on axial force,side friction resistance and the deformation of the composite piles,the test results showed that uplift load-displacement（P-S） curves of piles varied slowly.Pipe pile carried the majority of vertical load in the composite pile.Under the uplift loading,the bottom and middle part of pipe pile beared majority of structural loads and gradually decreased upward along the pile.