Prototype Loading Tests on the Mechanical behaviors of the Shield Lining Structure of a Water Storage and Sewage Tunnel

EasyChair Preprint 1808

Abstract

A sophisticated and flexible testing system that can simulate both external water-soil pressures and inner water pressure was designed, based on which both single-ring and three-ring full-scale loading tests were conducted, and some interesting observations were made: increasing inner water head decreased the axial force, which thereby increased the lining deformation; the bending moment transferring mechanism was evident in the three-ring tests due to staggered fabrication, which significantly reduced the structural deformation comparing with the single-ring tests; the structural deformation accumulated slightly during the water inflow and drainage cycles, and the structural deformations remained stable after nine loading cycles; the internal forces increased and convergence deformations decreased as hoop effect was caused by the uniformly distributed grouting pressures; increasing longitudinal thrust made the 3D effects more obvious but the influence of increasing longitudinal thrust was limited as the structural deformation became approximately saturated when the longitudinal thrust exceeded a certain threshold value; compared with the increasing of the buried depth, the sensitivity of the lining deformation to the coefficients of subgrade reaction was more obvious during the increasing of the inner water head, and the deformation values at the UST state decreased linearly with the coefficients; both the cracking process captured by DIC technique and measured overall deformations showed that the lining structure failed when the inner water head exceeded 65m (ultimate limit states) 

Keyphrases: Inner water head, Strata resistance, loading test, mechanical behavior, shield tunnel

@booklet{EasyChair:1808,
  author    = {Yeting Zhu and Yanfei Zhu and Qi Wang and Zixin Zhang and Xin Huang and Wei Liu},
  title     = {Prototype Loading Tests on the Mechanical behaviors of the Shield Lining Structure of a Water Storage and Sewage Tunnel},
  howpublished = {EasyChair Preprint 1808},
  year      = {EasyChair, 2019}}