超孔隙水压力引起的压桩力变化  

Change of pile pressing force caused by excess pore water pressure

作　　者：张飞[1] 王东[1] 欧明喜[1] 潘紫伟 段玲玲 ZHANG Fei;WANG Dong;OU Mingxi;PAN Ziwei;DUAN Lingling(Faculty of Civil Engineering and Mechanics,Kunming University of Science and Technology,Kunming Yunnan 650500,China)

机构地区：[1]昆明理工大学建筑工程学院,云南昆明650500

出　　处：《工业安全与环保》2023年第8期1-6,共6页Industrial Safety and Environmental Protection

基　　金：国家自然科学基金(51968036)。

摘　　要：在静压管桩施工过程中,沉桩引起的超孔隙水压力可能造成后续沉桩困难。传统的压桩力都是通过现场压桩试验或者采用静力触探试验数据来估算得到,并未考虑超孔隙水压力对沉桩的影响。通过超孔隙水压力产生和消散过程中土体应力的变化,得到基于超孔隙水压力消散的静压桩压桩力的估算方法。通过与工程实例相对比,计算得出的沉桩终压力符合实际施工中的沉桩终压值,为沉桩终压的判断和静压桩桩机的选择提供依据。针对沉桩困难情况,提出用设置桩间应力释放孔方式来减少超孔隙水压力。研究表明:应力释放孔能够有效的隔断超孔隙水压力的传递路径,合理的应力释放孔能使后续沉桩位置的超孔隙水压力减少40%~60%,为群桩的连续施工提供可能。In the process of static pressure pipe pile construction,the excess pore water pressure caused by pile driving may cause the subsequent pile driving difficulties.The traditional pile driving force is estimated by field pile driving test or static penetration test data,without considering the influence of excess pore water pressure on pile driving.In this paper,we obtain the estimation method of piling force of hydrostatic pile based on the dissipation of super pore water pressure during the process of generation and dissipation.By comparing with engineering examples,the calculated final pile pressure accords with the final pile pressure value in actual construction,which provides a basis for the judgment of final pile pressure and the choice of static pile piling machine.In view of the difficult situation of pile driving,the method of setting stress release holes between piles is proposed to reduce the excess pore water pres-sure.The research shows that the stress release holes can effectively cut off the transfer path of excess pore water pres-sure,and the reasonable stress release holes can reduce the excess pore water pressure in the subsequent pile driving position by 40%~60%,which provides the possibility for the continuous construction of pile group.

关 键 词：静压桩 超孔隙水压力 压桩力 应力释放孔 FLAC3D 

分 类 号：TU473.1[建筑科学—结构工程]