冲击荷载作用下的岩体层裂是围岩屈曲失稳及岩爆的重要诱发因素。为研究围岩内部浅层节理对层裂行为的影响,采用相关键元胞力学模型(Correlated Lattice Bond CellCLBC)对此问题进行数值模拟研究。为了便于分析,以冲击荷载作用下不含节...冲击荷载作用下的岩体层裂是围岩屈曲失稳及岩爆的重要诱发因素。为研究围岩内部浅层节理对层裂行为的影响,采用相关键元胞力学模型(Correlated Lattice Bond CellCLBC)对此问题进行数值模拟研究。为了便于分析,以冲击荷载作用下不含节理的石梁层裂作为参考,将其层裂裂纹作为参考裂纹,层裂位置作为参考位置。相对于参考位置,分别在石梁中预设平行裂纹和斜裂纹组(相对于参考层裂裂纹),然后模拟相同荷载作用下的层裂行为。研究结果表明:浅层节理是否对岩体层裂产生影响取决于其相对参考层裂的位置和夹角。当平行节理位于参考层裂以内(远离自由面)时,平行节理对层裂没有影响;而当其处于参考层裂以外(近于自由面)时,应力波将其拉开、扩展,形成阶梯状层裂。对于斜节理组情形则更为复杂,但对于不同斜节理组其共同点都会在参考位置处产生层裂,并且表层岩石(层裂以外)都会被切割成块体沿斜节理方向弹出。当斜节理组位于参考位置以内时,斜节理发生扩展至自由面;当其位于参考位置以外时,只是在参考位置发生层裂;而当其跨越参考位置延伸至自由面时,在参考位置以内会产生平行于斜节理的衍生裂纹。该研究揭示了含浅层节理的岩体层裂规律,为分析围岩层裂行为提供了有意义参考,进而为进一步分析围岩屈曲失稳和岩爆提供必要的前提。展开更多
The expansion joints are expected to have movement capacity, bearing capacity for static and dynamic loading, water-tightness, low noise emission and traffic safety. In particular, the failure due to impact loading is...The expansion joints are expected to have movement capacity, bearing capacity for static and dynamic loading, water-tightness, low noise emission and traffic safety. In particular, the failure due to impact loading is the main reason for the observed damages. The problem of dynamic behavior of the expansion joints is so complex that we shall focus our attention on the impact factor for vehicle load that is governed by traffic impact. In order to overcome this difficulty, the cantilever-toothed aluminum joint (finger joint) is one of the promising joints under impact loading. In this study, from the viewpoint of design methodology, numerical studies for impact behavior were conducted for aluminum alloy expansion joints with perforated dowels. The design impact factor for the expansion joints with the perforated dowels against traffic impact loading was examined by using numerical simulations.展开更多
基金financially supported by the National Natural Science Foundation of China(No.51365014)the Industrial Support Key Project of Jiangxi Province,China(No.20161BBE50072)
文摘冲击荷载作用下的岩体层裂是围岩屈曲失稳及岩爆的重要诱发因素。为研究围岩内部浅层节理对层裂行为的影响,采用相关键元胞力学模型(Correlated Lattice Bond CellCLBC)对此问题进行数值模拟研究。为了便于分析,以冲击荷载作用下不含节理的石梁层裂作为参考,将其层裂裂纹作为参考裂纹,层裂位置作为参考位置。相对于参考位置,分别在石梁中预设平行裂纹和斜裂纹组(相对于参考层裂裂纹),然后模拟相同荷载作用下的层裂行为。研究结果表明:浅层节理是否对岩体层裂产生影响取决于其相对参考层裂的位置和夹角。当平行节理位于参考层裂以内(远离自由面)时,平行节理对层裂没有影响;而当其处于参考层裂以外(近于自由面)时,应力波将其拉开、扩展,形成阶梯状层裂。对于斜节理组情形则更为复杂,但对于不同斜节理组其共同点都会在参考位置处产生层裂,并且表层岩石(层裂以外)都会被切割成块体沿斜节理方向弹出。当斜节理组位于参考位置以内时,斜节理发生扩展至自由面;当其位于参考位置以外时,只是在参考位置发生层裂;而当其跨越参考位置延伸至自由面时,在参考位置以内会产生平行于斜节理的衍生裂纹。该研究揭示了含浅层节理的岩体层裂规律,为分析围岩层裂行为提供了有意义参考,进而为进一步分析围岩屈曲失稳和岩爆提供必要的前提。
文摘The expansion joints are expected to have movement capacity, bearing capacity for static and dynamic loading, water-tightness, low noise emission and traffic safety. In particular, the failure due to impact loading is the main reason for the observed damages. The problem of dynamic behavior of the expansion joints is so complex that we shall focus our attention on the impact factor for vehicle load that is governed by traffic impact. In order to overcome this difficulty, the cantilever-toothed aluminum joint (finger joint) is one of the promising joints under impact loading. In this study, from the viewpoint of design methodology, numerical studies for impact behavior were conducted for aluminum alloy expansion joints with perforated dowels. The design impact factor for the expansion joints with the perforated dowels against traffic impact loading was examined by using numerical simulations.
