ZHANG Chuan-qing, LÜ Hao-an, LIU Xiao-yan, et al. Mechanism research of a new constant resistance yielding device for tunnels[J]. 2020, 41(12): 4045-4053.
ZHANG Chuan-qing, LÜ Hao-an, LIU Xiao-yan, et al. Mechanism research of a new constant resistance yielding device for tunnels[J]. 2020, 41(12): 4045-4053.DOI: 10.16285/j.rsm.2020.0436.
The constant resistance yielding support is the ideal form of support for squeezing tunnel. Current technology is difficult to satisfy the safety requirements of high bearing capacity
large deformation and load stability at the same time. In response to this problem
the conversion constant resistance yielding device (CCYD) was developed inspired by the metal drawing process in combination with the characteristics of steel arch support. In this paper
the working principle of the CCYD was discussed
and its mechanical response law and characteristics were analyzed. Through the indoor test and numerical simulation
the influence of the design parameters was analyzed
and the performance measurement index of the conversion constant resistance yielding device was determined. The analysis shows that: 1) The conversion constant resistance yielding device can constantly resist deformation under pressure; when installed in the steel arch joint allowing it to be part of the steel arch
the device can ensure the stability of the arch
improve its large deformation adaptability while providing constant support for the surrounding rock. 2) Based on the four design parameters: the cone angle
the friction coefficient
the cross-section shrinkage rate and the diameter of the pressure bar
the device can realize pressure resistance and pressure control with satisfactory load stability
which can provide important technical support for soft-rock tunnel large deformation and the stability control of support.