托桩的荷载传递机理分析及实例验证

Analysis Of Load Transfer Mechanism of Bottom-loaded Piles and Its Verification

本文基于荷载传递函数概念，建立了托桩摩阻力传递机理的力学模型。结果表明：托桩桩身轴力、位移沿桩身分布呈上弯分布，与压桩的下弯分布相反。随剪切比刚度β增大，轴力分布越来越集中在荷载作用处，向上传递的荷载不断减小，桩身各截面位移也相应减少。此外该模型也可便于考虑多层土中托桩摩阻力性状。最后举了一工程实例进行了验证。

Based on load transfer function, a load transfer model of frictional resistances of bottom-loaded piles is set up. The results indicate that the distribution curves of axial forces and sectional settlement are protuberant, which is contrary to top-loaded piles. With the increase of shear ratio stiffness, the axial forces are concentrated on load action spot more and more; the load and settlement transferred upwards shaft decrease correspondingly. Moreover, the model can take frictional resistances of layered soils into consideration. Finally an actual engineering case is given to verify it.