人工冻结法凿井井口房地基不均匀沉降机理分析  

Mechanism Analysis of the Uneven Settlement of the Foundation around the Wellhead in Artificial Freezing Shaft Sinking

作　　者：纪文杰 汪春芹 姚直书[1] 薛维培 JI Wenjie;WANG Chunqin;YAO Zhishu;XUE Weipei(School of Civil Engineering and Architecture,Anhui University of Science and Technology,Huainan 232001,China;Hefei Design and Research Institute of Coal Industry,Hefei 230041,China)

机构地区：[1]安徽理工大学土木建筑学院,安徽淮南232001 [2]煤炭工业合肥设计研究院有限责任公司,安徽合肥230041

出　　处：《宿州学院学报》2020年第6期80-84,共5页Journal of Suzhou University

基　　金：国家自然科学基金项目(51674006);中国博士后科学基金项目(2018M642502);安徽省自然科学基金青年项目(1908085QE185);安徽省高等学校自然科学研究重点项目(KJ2018A0098)。

摘　　要：为分析人工冻结法凿井井口房地基的不均匀沉降机理,对某矿副井井口房地基的冻融土进行了物理力学性能试验,并对重塑土样冻结前和融化后的物理力学特性进行对比研究,结果表明:经冻融后的土体含水率增加、密度减小、孔隙率增加、粘聚力减小,内摩擦角变化较小,压缩模量减小。通过现场勘探发现:冻结圈内土体力学强度比冻结圈外土体力学强度明显减弱。综合分析表明,土体因冻融而改变了物理力学性质,导致冻结影响范围内的地基承载力降低,并且自冻结圈向外土体受冻融影响程度不同,地层融沉呈漏斗型分布,从而造成井口地基不均匀沉降。In order to research the mechanism of uneven settlement of the foundation around the wellhead in artificially freezing shaft sinking method,physical and mechanical properties of the frozen and thawed soil were tested.Physical and mechanical properties of the unfrozen and melted soil of the remolded sample were compared.The results show that the moisture content of the frozen and thawed soil increases;the density decreases and the void ratio increases.At the same time,the cohesive force of frozen and thawed soil decreases;the internal friction angle does not change much,and the compressive modulus decreases.Through field exploration and discovery,it finds the mechanical strength of soil in frozen circle is weaker than that of the outside.The comprehensive analysis shows that the physical and mechanical properties of soil is changed by freezing and thawing,which results in the decrease of foundation bearing capacity in the influence scope of freezing.Moreover,the influence of freezing-thawing on the soil varies in different levels of the freezing-thawing circle,and the thawing settlement is funnel-shaped,which results in the uneven settlement of the foundation around the wellhead.

关 键 词：冻结法凿井 地基 融沉 不均匀沉降 

分 类 号：TD223[矿业工程—矿井建设]