冻融循环层理砂岩冲击荷载下应变率特性研究

Study on Strain Rate Characteristics of Frozen-thawed Bedding Sandstone under Impact Load

随着现代战争武器的杀伤力不断增强,剧烈的侵彻和爆炸作用在地壳中形成能量巨大的应力波,对国防工程、民用建筑的地下围岩和地面工程造成强烈的冲击作用。同时,层理岩石广泛存在于自然界且力学性质复杂,直接关系到工程的可靠性。本文介绍了Φ100 mm SHPB试验系统结构及其基本原理;基于SHPB冲击试验平台对经历0、20、40次冻融循环的垂直、平行层理试样进行6、8、10、12、14 m/s弹速下的冲击压缩试验;对冲击作用下冻融循环层理砂岩的应变率特性进行分析,研究了冲击作用下冻融循环层理砂岩的强度、变形性质,针对性地对岩石的层理动荷载关系进行了力学响应的试验研究。试验结果对高寒、冻融地区的岩土工程及地下工程施工具有较强指导意义。

As the lethality of modern warfare weapons continues to increase,the intense penetration and explosions create a huge energy stress wave in the earth’s crust,which has a strong impact on the underground surrounding rock and ground engineering of national defense projects and civil buildings. At the same time,the bedding rock is widely existed in nature and the mechanical properties are complex,which is directly related to the reliability of the project. This paper first introduces the structure and basic principles of the Φ100 mm SHPB test system. Subsequently,based on the SHPB impact test platform,the vertical and parallel layered samples that have undergone 0,20,and 40 freeze-thaw cycles are subjected to impact compression tests at 6,8,10,12,and 14 m/s. Finally,the strain rate characteristics of the frozen-thawed bedding sandstone under impact are analyzed,the strength and deformation properties of the frozen-thawed bedding sandstone under impact are studied,and the mechanical response of the bedding-dynamic load relationship of the rock is studied. The test results have a strong guiding significance for geotechnical engineering and underground engineering construction in high-cold,freezethaw areas.