输电线路大直径人工挖孑L扩底桩基础的承载力试验研究

为在我国西南山区全方位高低腿基础设计方案中采用大直径人工挖孔扩底灌注桩基础，进行了1基直线塔和1基转角塔单腿人工扩底灌注桩基础施加水平、上拔、下压荷载试验。试验结果表明，高低腿基础采用人工挖孔扩底灌注桩基础因充分利用了原状土良好的力学特性而具有较高的承载能力，并表现出刚性短桩的工程特性。根据试验荷载与基础位移关系所确定的单桩承载力可以满足线路基础的承载稳定性要求。

Field Test on Bearing Capacity of Man-made Hole Pedestal Pile with Large Diameter for Foundations in Power Transmission Line

In order to apply the foundations of man-made hole driven cast-in pedestal pile with large diameter in design of transmission foundations with legs at different heights in southwestern mountain areas of China, 3 kinds of tests, including application of horizontal, uplifting and compressive loads have been carried out on the man-made pedestal piles of an angle tower and a tangent tower. The tests have proved that the foundations with legs at different heights have a good capability of high bearing capacity due to good mechanical property of the undisturbed soil applied by the man-made hole driven cast-in-place pedestal piles and present the engineering features of stiff short piles. The bearing capacity of the single pile determined by the relations of testing load to the foundation displacement can meet the bearing stable demand of transmission foundation.