挖钻孔柱基底沉渣对基础承载力的影响  

Analysis and research on the influence of the sediment on the bearing capacity of the foundation

作　　者：李智平 张红[2] 龙建辉 LI Zhiping;ZHANG Hong;LONG Jianhui(Shanxi Metallurgical Rock-Soil Engineering Investation Co.,Ltd,Taiyuan 030002,China;The Third Geological Exploration Institute of China Metallurgical Geology Bureau,Taiyuan 030002,China;Taiyuan University of Technology,Taiyuan 030024,China)

机构地区：[1]山西冶金岩土工程勘察有限公司,山西太原030002 [2]太原理工大学,山西太原030024 [3]中国冶金地质总局第三地质勘查院,山西太原030002

出　　处：《粘接》2022年第2期112-115,共4页Adhesion

基　　金：山西省自然科学基金项目(项目编号:201801D121033)。

摘　　要：针对传统灌注桩基础施工过程中产生沉渣影响桩基承载力发挥的问题,提出用荷载传递性状现场测方法,对单桩极限承载力、桩端阻力和桩端侧摩阻力受沉渣影响的机理。试验结果表明:桩的破坏形式受到沉渣厚度的影响,沉渣厚度大,桩破坏形式为刺入破坏;沉渣厚度小,桩破坏形式为桩端土压缩变形。相同桩顶荷载条件,沉渣厚度与桩顶沉降量成正比,与单桩极限承载力成反比。当沉渣厚度较大时,端阻最大损失可达80%,侧阻损失可达70%,压密后,桩端阻力慢慢的接近正常桩。处理沉渣的有效方式为反循环清渣工艺结合桩底高压注浆工艺。In view of the problems that sediment is produced in the construction of traditional cast-in-place pile foundation,which affects the bearing capacity of pile foundation,the paper puts forward the method of static load test and field test of load transfer characteristics of pile,and analyzes the influence mechanism of sediment on ultimate bearing capacity,pile end resistance and side friction resistance of pile end.The results show that the thickness of sediment has an impact on the failure form of pile.The thickness of sediment is large,the pile failure is the penetration failure,the thickness of sediment is small,and the pile end soil is compressed;under the same pile top load condition,the sediment thickness is proportional to the settlement of the pile top,which is inversely proportional to the ultimate bearing capacity of a single pile;when the thickness of sediment is large,the maximum loss of end resistance can reach 80%,and the side resistance is up to 80%.The loss can reach 70% and the resistance at the end of pile can be close to the normal pile after compaction;the reverse circulation slag cleaning technology and the high pressure grouting technology at the bottom of the pile are the effective ways to deal with the sediment.

关 键 词：沉渣 沉渣厚度 极限承载力 桩端阻力 桩侧摩阻力 

分 类 号：TU473.11[建筑科学—结构工程] TU473.14[建筑科学—土工工程]