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Analysis of the Vibration Responses of High-Speed Railway Tunnels Based on Damage Theory
(1 School of Civil Engineering and Architecture, Central South University, Changsha410075; 2 Faculty of Civil Engineering and Mechanics, Kunming University of Science and Technology, Kunming 650024)
Abstract Based on the known Mazars and Loland damage models, an elastic-plastic damage constitutive model for concrete is developed by introducing a damage variable to the Drucker-Prager yield function. Using the interface of the finite-difference software FLAC5.0, secondary development is carried out to program the proposed damage constitutive model. The dynamic vibration response of a high-speed railway tunnel on the Wuhan-Guangzhou Passenger Dedicated Line is calculated using the secondary developed damage model, which quantifies the damage of tunnel linings and lays a foundation for the analysis of fatigue lifetime prediction and a durability evaluation of highspeed railway tunnel structures. The results show that:1) the settlements at the tunnel floor and the peripheral deformations induced by the vibration load of the train are less than 4 mm; 2) the main adverse effect caused by train loading is an increase of tensile stress of the tunnel lining; 3) the maximum damage to the tunnel appears on the invert facing the surrounding soils; and 4) a vibration-induced stress wave attenuates very quickly in the tunnel lining structure and vibrations caused by train loading influence local parts of the tunnel floor.
Abstract：
Based on the known Mazars and Loland damage models, an elastic-plastic damage constitutive model for concrete is developed by introducing a damage variable to the Drucker-Prager yield function. Using the interface of the finite-difference software FLAC5.0, secondary development is carried out to program the proposed damage constitutive model. The dynamic vibration response of a high-speed railway tunnel on the Wuhan-Guangzhou Passenger Dedicated Line is calculated using the secondary developed damage model, which quantifies the damage of tunnel linings and lays a foundation for the analysis of fatigue lifetime prediction and a durability evaluation of highspeed railway tunnel structures. The results show that:1) the settlements at the tunnel floor and the peripheral deformations induced by the vibration load of the train are less than 4 mm; 2) the main adverse effect caused by train loading is an increase of tensile stress of the tunnel lining; 3) the maximum damage to the tunnel appears on the invert facing the surrounding soils; and 4) a vibration-induced stress wave attenuates very quickly in the tunnel lining structure and vibrations caused by train loading influence local parts of the tunnel floor.
2017, Vol. 54 