Stress Characteristics of Variable- section Lining Trolley of Super-large Section Tunnel

Abstract:

Based on the Badaling Great Wall Station of Beijing-Zhangjiakou High-speed Railway， the dynamic and static stresses of variable-section lining trolley of super-large section tunnel were studied， and the effect of cross-sectional changes on the trolley structure was analyzed. Numerical simulation was used to analyze the static stress characteristics of the trolley structure， and the field monitoring was used to analyze the dynamic stress characteristics of the trolley structure and the influence law of cross-sectional changes on the stress of the trolley structure. The results show that： the static stress and the displacement of the trolley structure are unevenly distributed， and each structure is variable， with some structures showing obvious stress concentration. During the pouring process， the stress is larger on the outside and smaller on the inside； the stress value is the largest when the trolley pouring area is located above the supporting structure， and the stress of the trolley structure is basically constant during the concrete solidification process. As the cross section of the trolley becomes larger， the stress of each trolley structure increases. The arch shoulder screw is the member with the greatest change in stress.

Key words:super-large section tunnel;lining trolley;stress characteristics;variable-section;structural design