竖向荷载对砂土中大直径桩水平加载反应的影响

Effect of Vertical Loads on the Lateral Loaded Response of Large Diameter Pile Foundations in Sandy Soil

大直径桩基础,因为兼备优良的水平和竖向承载性能,经常作为大型海上风力发电机组和海上塔楼的基础同时承受水平和竖向荷载。但在进行桩基础承载力设计时,水平承载力和竖向承载力通常分开进行,并假定二者不存在相互作用。实际上,目前已经进行了很多针对二者相互作用的研究,研究表明竖向承载力和水平承载力之间存在耦合效应,但研究结论并不一致。本文通过室内模型试验对砂土中大直径单桩在竖向和水平联合加载下的水平响应进行研究,试验中通过控制不同的竖向和水平荷载加载比例考察竖向荷载对大直径单桩水平响应的影响。试验结果表明砂土中竖向力的作用增加了大直径单桩的水平承载力。

Large diameter pile foundations with their high lateral and vertical bearing capacity are usually used to support offshore wind turbines and offshore towers subjected to both horizontal loads and vertical loads. However,the pile foundation design is carried out separately for vertical bearing capacity and horizontal bearing capacity,and assuming that there is no interaction between these two loads. Actually,there have been many research on the interaction between these two loads at present,which shows that there is coupled effect between these two loads,but conclusions are not consistent. The main purpose of the present work is to investigate the effect of vertical loads on lateral behavior of large diameter pile foundation under loads combined of vertical and horizontal loads in sandy soil through laboratory model test. In the model test,we consider the influence of different ratios of vertical loads to horizontal loads on the lateral behavior of the pile foundation. Results show that the presence of vertical loads strengthens the lateral bearing capacity of the pile foundation.