大直径三岔双向挤扩灌注桩及其应用

对三岔双向挤扩灌注桩在衡水某工程中的应用进行了总结,并与普通灌注桩施工方案进行了经济效益比较.分析了三岔双向挤扩灌注桩的优势,其应用提高了单桩承载力,减少了桩数,使桩位布置更合理.通过分析沉降观测数值,证明三岔双向挤扩灌注桩应用的合理性.对《三岔双向挤扩灌注桩设计规程》JGJ171-2009中关于大直径单桩竖向极限承载力标准值的计算提出了建议.

Application of Large Diameter Cast-in-place Piles with Expanded Branches and Bells By 3-way Extruding Arms

The authors summarize application of cast-in-place piles with expanded branches and bells by 3-way extruding arms of some project in Hengshui,make comparison with common piles and analyze the advantages of cast-in-place piles with expanded branches and bells by 3-way extruding arms.Application of cast-in-place piles with expanded branches and bells by 3-way extruding arms can improve bearing capacity of single pile,reduce the number of piles,and make the pile arrangement more reasonable.According to the analysis of the settlement observation value,the rationality of the application of cast-in-place piles with expanded branches and bells by 3-way extruding arms can be proved.The authors give advice on calculation of ultimate bearing capacity of the large diameter single pile in Design specification for cast-in-place piles with expanded branches and bells by 3-way extruding arms JGJ171—2009.