爆炸载荷作用下岩石损伤破裂过程的数值分析  

Numerical analysis of damage and crack process of rock under explosive loading

作　　者：冯春[1] 李世海[1] 周东[1] 张青波[1] 

机构地区：[1]中国科学院力学研究所,北京100190

出　　处：《岩土工程学报》2014年第7期1262-1270,共9页Chinese Journal of Geotechnical Engineering

基　　金：国家重点基础研究发展计划(973)计划(2010CB731506);国家科技支撑计划(2012BAK10B00);国家自然科学基金青年基金项目(11302230)

摘　　要：探讨了JWL爆源模型与朗道模型、应变强度分布模型与应变软化模型的异同点，并在CDEM源程序中引入了JWL爆源模型及应变强度分布模型。利用改进的CDEM程序研究了爆炸载荷作用下岩石损伤破裂的物理过程，重点分析了压碎区、破损区比半径及总破裂度随岩石应变强度的变化规律。研究发现：①最大应变强度是控制岩石破裂范围的关键量，最大应变强度从0．5％增加至5％，压碎区比半径从37降至4，破损区比半径从45降至12，岩石总破裂度从55％降至5％；②相同应变强度情况下，岩石更容易发生剪切破坏，剪切破坏产生的破坏区域的比半径较拉伸破坏产生的大2～5，总破裂度大3％左右；③拉伸破坏为主导（拉伸应变强度主控），破损区的裂缝将沿着径向平直发展；剪切破坏为主导（剪切应变强度主控），破损区的裂缝将弧状向外扩展。The similarities and differences between JWL model and Landau model and those between strain strength distribution model and strain softening model are discussed, and the JWL model and strain strength distribution model are adopted and introduced in CDEM source program. By using the improved CDEM program, the failure process of rock under explosive loading is studied, and the dimensionless radii of crushed and damage zones and the total fracture degree are mainly analyzed. According to the study, some useful results are obtained： （1） The maximum strain strength is the key parameter to control the failure process. With the increase of the maximum strain strength, from 0.5% to 5%, the dimensionless radius of crushed zone decreases from 37 to 4, the dimensionless radius of damage zone decreases from 45 to 12, and the total fracture degree of rock decreases from 55% to 5%. （2） Under the same strain strength, the occurrence of shear failure is easier than that of tensile failure. The dimensionless radius of failure zone due to shear failure is 2-5 larger than that due to tensile failure, and the total fracture degree is 3% larger. （3） If the tensile failure is the main factor, the fractures in damage zone will propagate along the radial direction straightly. If the shear failure is dominant, the curved fractures will happen.

关 键 词：数值分析 爆炸 岩石 损伤破裂 JWL 应变强度分布 

分 类 号：TU45[建筑科学—岩土工程]