大厚度湿陷性黄土地区风电扩底灌注桩单桩承载力试验分析

摘要

In order to study the load-bearing characteristics of wind turbine under-reamed bored pile in large-thickness collapsible loess area,the vertical load test of single pile is carried out by using slow-loading method for a wind farm in Dingbian,Shaanxi Province.The analyses on test data show that,(a) the axial force of pile body at same horizontal section is gradually increased with the increase of load,and the axial force of pile body is gradually decreased from top to bottom with the increase of buried depth of pile under the action of same load;and (b) during the process of loading,the pile side resistance is slightly decreased with the increase of buried depth of pile,and the pile side resistance at same horizontal section is gradually increased and then tends to a stable value with the increase of load.%为了研究大厚度湿陷性黄土地区风电扩底钻孔灌注桩的承载特性,结合陕北定边某风电场试桩过程,采用慢速维持荷载法进行单桩竖向抗压静载试验,对试验结果进行分析.结果表明:随着荷载等级的不断增加,同一水平断面处桩身轴力逐渐增加,在同一荷载等级的情况下,随着桩入土深度的增加,桩身轴力由上到下逐步减小;施加荷载的过程中,桩侧阻力随着桩入土深度的增加而略微减小,随着荷载等级的增加,同一水平断面处,桩侧阻力逐级增加,增加到一定程度后趋于稳定值.