Abstract The rheological effect of soft and weak surrounding rocks can easily lead to the cracking of tunnel sec? ondary lining, affecting the safety and durability of the structure. In view of this, this paper takes the Dujiashan tunnel on Guangyuan-Gansu Expressway as an example and establishes a numerical calculation model based on Weibull damage distribution to investigate the damage evolution behaviors of the secondary lining under rheological load. The results show that: (1) if the secondary lining is in good contact with the surrounding rock, the lining cracking area is distributed near the arch waist, arch foot, as well as the top and bottom of the arch respectively when the lateral pressure coefficients are λ=0.5,1 and 2; (2) the cavity has a great impact on the lining cracking area and the order of the occurrence of the cracking, that is, the cracking is first induced in the concrete near the cavity, and the concrete at that specific location will all produce quite serious damage; and (3) the influence of the geostress on the damage patterns of the secondary lining with cavities can be divided into two kinds: the impact on the order of the occurrence of the damage location, but not on the final damage pattern of the structure, or the impact on both the order of the damage occurrence and the final damage pattern of the structure.
Abstract：
The rheological effect of soft and weak surrounding rocks can easily lead to the cracking of tunnel sec? ondary lining, affecting the safety and durability of the structure. In view of this, this paper takes the Dujiashan tunnel on Guangyuan-Gansu Expressway as an example and establishes a numerical calculation model based on Weibull damage distribution to investigate the damage evolution behaviors of the secondary lining under rheological load. The results show that: (1) if the secondary lining is in good contact with the surrounding rock, the lining cracking area is distributed near the arch waist, arch foot, as well as the top and bottom of the arch respectively when the lateral pressure coefficients are λ=0.5,1 and 2; (2) the cavity has a great impact on the lining cracking area and the order of the occurrence of the cracking, that is, the cracking is first induced in the concrete near the cavity, and the concrete at that specific location will all produce quite serious damage; and (3) the influence of the geostress on the damage patterns of the secondary lining with cavities can be divided into two kinds: the impact on the order of the occurrence of the damage location, but not on the final damage pattern of the structure, or the impact on both the order of the damage occurrence and the final damage pattern of the structure.
CHENG Gang1 WANG Jun2
.Study on Damage Behaviors of Tunnel Secondary Lining under Rheological Load[J] MODERN TUNNELLING TECHNOLOGY, 2021,V58(3): 123-129
2021, Vol. 58 