卵石层钢板桩插打的引孔回填料设计与成桩试验研究  

Design of backfill materials for driving steel sheet piles and pile forming tests in gravel layer

作　　者：蔺鹏臻[1] 马俊军 LIN Peng-zhen;MA Jun-jun(School of Civil Engineering,Lanzhou Jiaotong University,Lanzhou 730070,China)

机构地区：[1]兰州交通大学土木工程学院,甘肃兰州730070

出　　处：《岩土工程学报》2022年第1期187-193,共7页Chinese Journal of Geotechnical Engineering

基　　金：国家自然科学基金重大项目(11790281);甘肃省建设科技项目(JK2021-03)。

摘　　要：为解决河道卵石层地质钢板桩插打施工的难题,结合工程现场实际开发了一种以粉质黏土、膨润土、锯末、水泥等材料组成的新型引孔回填料。通过多因素正交试验研究了新型回填料的材料组分对凝固体抗压、抗剪和抗渗性能的影响规律,给出了满足设计要求的施工配合比。通过现场钢板桩的对比试验,分析了新型引孔回填料的嵌固效果。研究结果表明:粉质黏土掺量对回填料凝结体黏聚力和抗压强度的影响最为显著,锯末掺量对回填料凝结体内摩擦角和抗渗性能的影响最为显著;在最大水平荷载作用下,采用新型引孔回填料后钢板桩的桩顶平均水平加、卸位移、压应力和地基水平反力系数的比例系数分别是采用现场渣土回填后钢板桩的46%,28%,1.39%,2.8%,证明采用新型回填料后的土体刚度更大,抵抗变形的能力更强,对钢板桩的嵌固效果更好。该新型引孔回填料具有取材方便、施工便捷和材料性能好的综合优点,可在同类型工程施工中推广应用。In order to solve the construction problem of inserting and driving steel sheet piles in pebble layer of rivers,a new type of lead-through backfill made of clay,bentonite,sawdust,cement and other materials is developed.Using the multi-factor orthogonal test method,the influence law and mechanism of the components of the new backfill materials on the compression,shear and impermeability properties of the backfill-solidified body are studied,and the construction mix proportion meeting the design requirements is given.The actual embedding effect of steel sheet piles is verified through the field comparative tests.The research results show that the content of silty clay has the most significant effect on the cohesion and compressive strength of the backfill aggregate,while the sawdust content has the most significant effect on the friction angle and impermeability of backfill aggregate.Under the maximum horizontal load,the average horizontal loading displacement,unloading displacement,compressive stress and proportional coefficient of horizontal reaction coefficient of foundation at the steel sheet pile top after using the new type lead hole backfill are 46%,28%,1.39%,and 2.8%,respectively,of the steel sheet pile after backfilling with on-site muck,which proves that the new type of backfill has greater soil stiffness and stronger resistance to deformation.The actual embedding effect of the piles is better.The new type of lead backfill has the comprehensive advantages of convenient material acquisition,convenient construction and good material performance,and can be popularized and applied in the construction of the same type of projects.

关 键 词：钢板桩 卵石层 引孔回填料 正交试验 桩基试验 

分 类 号：TU470[建筑科学—结构工程] U445[建筑科学—土工工程]