弱化区对节理扩展及岩桥影响的研究

Study on the Influence of Weakening Area on Joint Expansion and Rock Bridge

使用ABAQUS对素混凝土梁节理扩展进行研究,研究了素混凝土梁在正常、有初始缺陷、缺陷隔离3种情况下的节理扩展。研究表明在节理扩展的轨迹前方设置诱导区,可以使节理前沿与弱化区形成新岩桥,此时岩桥弱化不再满足最大主应力准则。在弱化区与节理预扩展路径上设置隔离区能有效地隔断这种新的岩桥,岩桥的弱化不完全满足最大主应力准则(弱最大主应力准则)。该研究可以很好地对节理扩展轨迹进行控制,对于精确分析带有初始节理的结构加固具有重要意义。

ABAQUS is used to study the joints of concrete beams. The joint expanstion of plain concrete beams under normal conditions,initial defects and defect isocation is studied. The results show that the induced area is set in front of the trajectory of the joint extension,which can make the frontier and the weakened area to form a new rock bridge. At this time,the weakening of the rock bridge no longer satisfies the maximum principal stress criterion. Setting up the isolation zone in the weakened zone and the pre-extended path can effectively cut off the new rock bridge,and the weakening of the rock bridge does not satisfy the maximum principal stress criterion( weak maximum principal stress criterion). The study can be very good control of the joint expansion trajectory,for the precise analysis of the reinforcement zone,the structure of the initial joint has very important significance.