Abstract：The failure phenomenon and damage characteristics are research focuses of failure analysis and load-carrying performance of segmental joints, which is of great significance to ensure the force safety of the joints. In this work, the compression-bending failure tests of segmental joint under positive and negative bending actions were carried out, and the macroscopic failure behaviors such as concrete cracks, collapse, bolt stress and deformation, and joint displacement were analyzed. The acoustic emission technique was adopted to quantitatively analyze the microscopic damage characteristics such as damage evolution process and damage distribution of joint concrete. The results show that: the failure of segmental joints under high axial compression are characterized by four main cracks, micro-cracks and crushed zone in the joint surface followed by crushed concrete in the compression zone. The bending dominated bolt deformation mode can be seen, and the bolt deformation under negative bending is more obvious. A significant peak in the acoustic emission count and energy during the failure process of joint can be observed, which corresponds to the joint failure phenomenon that the micro cracks on the joint surface develop to visible cracks, indicating that the load-carrying state of joint changes significantly. The damage range of joint along the direction vertical to the joint surface is 0.855h (h as the joint thickness) in positive bending side and 0.584h in negative bending side, respectively. The damage range of joint along the direction of segment width is 0.2b (b as the average segment width occupied by a single bolt equal to the segment width divided by the number of bolts) on either side of the bolt.
张力 封坤 何川 肖明清. 盾构隧道管片接头破坏特征及损伤特性试验研究[J]. 土木工程学报, 2021, 54(5): 98-107.
Zhang Li Feng Kun He Chuan Xiao Mingqing. Experimental study on failure behaviors and damage characteristics of #br#
segmental joints of shield tunnels. 土木工程学报, 2021, 54(5): 98-107.
