考虑渗流、非轴对称荷载作用的隧道围岩塑性区分析  

Analysis of the Plastic Zone of Surrounding Rock Under Seepage and a Non-Axisymmetric Load

作　　者：高召宁[1] 孟祥瑞[1] 王广地[2] 

机构地区：[1]安徽理工大学煤矿安全高效开采省部共建教育部重点实验室,淮南232001 [2]西南交通大学土木工程学院.成都610031

出　　处：《现代隧道技术》2014年第2期70-75,共6页Modern Tunnelling Technology

基　　金：国家自然科学基金项目(51074003,51074005);国家自然科学基金委员会与神华集团有限公司联合资助项目(51174255);中国博士后科学基金资助项目(2012T50567,2011M501037)

摘　　要：文章考虑了渗流体积力,推导了渗流场作用下隧道围岩的应力分布规律和塑性区表达式,并分析了隧道塑性区范围与孔隙水压力、侧压系数,以及岩体强度和初始地应力比值k之间的关系。研究表明:渗流场仅对塑性区范围有影响,对塑性区形状没有影响;随着侧压系数以及岩体强度和初始地应力比值k的不同,渗流对隧道围岩塑性区范围的影响沿不同方向表现出各向异性,且随着侧压系数以及岩体强度和初始地应力比值k的增大各向异性程度逐渐弱化;侧压系数、岩体抗压强度与初始地应力比值k不仅影响塑性区的范围,同时影响着塑性区的形状,当k<1时,侧压系数对隧道塑性区的范围和形状起主要作用;当k>1时,岩体强度对隧道围岩塑性区的范围和形状起主要作用,且随着岩体抗压强度的增大,塑性区范围逐渐减小,在隧道两帮处随侧压系数的减小易出现塑性区。Taking the seepage body force into consideration, this paper derives the rock stress distribution and plastic zone expressions under the seepage field and analyzes the relationships of the plastic zone range to the porewater pressure, lateral pressure coefficient and the ratio K between the rock mass strength and initial geostress. The results show that the seepage field has an effect on the plastic zone range, but not on its shape. With variation of lateral pressure coefficients and K values, the effect of seepage on the plastic zone range presents anisotropy along different directions. Furthermore, the anisotropic degree decreases gradually with the increase of the lateral pressure coefficient and K value. The lateral pressure coefficient and the K value not only affect the plastic zone range, but also its shape. When K〈 1, the effect from the lateral pressure coefficient plays an important role. Whereas, rock mass strength plays the leading role when K〉 1, namely, the plastic zone range decreases gradually with the increase of the rock＇s compressive strength. Additionally, the plastic zone is more likely to appear at the two sides of the tunnel with a decrease of the lateral pressure coefficient.

关 键 词：隧道围岩 渗流 塑性区 侧压系数 

分 类 号：U451.2[建筑科学—桥梁与隧道工程]