沉积结构面及其对岩体力学性质的影响  

Depositinonal structure planes and their influence on the mechanical properties of sedimentary rock mass

作　　者：孟召平[1,2] 陆鹏庆[1] 贺小黑[1] 

机构地区：[1]中国矿业大学资源与地球科学系,北京100083 [2]三峡大学三峡库区地质灾害教育部重点实验室,湖北宜昌443002

出　　处：《煤田地质与勘探》2009年第1期33-37,共5页Coal Geology & Exploration

基　　金：国家重点基础研究发展计划(973计划)项目(2007CB209405);国家自然科学基金项目(40772100);全国优秀博士学位论文作者专项资金项目(200247);高等学校博士学科点专项科研基金项目(20050290009)

摘　　要：基于沉积结构面的成因类型,通过理论分析和实验研究,分析了沉积结构面的变形与破坏特征,研究了沉积结构面力学特征及其力学效应,提出了弱面型层理、层系或层系组界面和岩层面以及不整合面均为沉积构造弱面,这些弱面对沉积岩体力学性质产生重要的影响。分析了沉积岩体沿层面方向和垂直层面方向岩体力学性质的差异性。研究表明,垂直层面方向的纵波速度和弹性模量要比平行层面方向低;平行层面方向的抗拉强度要大于垂直层面方向;而平行层面方向的抗压强度与凝聚力小于垂直层面方向。沉积岩体易于产生垂直于结构面方向的张性破坏和沿结构面方向的剪切破坏,在采动影响下顶板岩体易于沿岩层层面产生离层破坏现象,这进一步揭示了沉积结构面变形与破坏机制.Based on the genetic types of depositional structure planes, the deformation and failure characters are analyzed and their mechanical characteristics and mechanical effects are studied through theoretical analysis and experimental investigation. It is shown that the weak plane of sedimentary structure such as the bedding of weak plane type, sets or cosets plane, bedded plane and unconformity interface will produce main influence on the mechanical properties of sedimentary rock mass.The differences of rock mass＇s mechanical properties in parallel and vertical directions of bedding plane are analyzed too. It is displayed that the compressional wave velocity and elastic modulus are lower in vertical directions compared with that of parallel, correspondingly the tensile strength is smaller while the compressive strength and cohesion are contrary. The sedimentary rock mass is prone to produce tensile failure in vertical directions of structure planes and shear failure in parallel directions. Therefore, the rock mass of coal roof tends to generate the destruction phenomenon of separation layer in the direction of stratification plane under the effect of mining. Further, the deformation and failure mechanism is revealed.

关 键 词：沉积结构面 岩体力学性质 力学效应 离层破坏 

分 类 号：TU452[建筑科学—岩土工程] P642.3[建筑科学—土工工程]