矩形装配式隧道接头的抗弯压性能数值研究

Flexural and Compressive Properties of Rectangular Fabricated Tunnel Joint

随着矩形装配式隧道在城市交通中的广泛应用,其接头的设计和性能研究备受关注。为此,研究设计了一种新型矩形隧道错缝榫接式接头。为了探讨其力学性能,采用数值模拟方法,分析了不同轴力和弯矩组合作用下,接头张开量、侧向位移、应力及应变、接缝面交错处应变和损伤特征变化规律。结果表明:当M≤1400 kN·m时,接缝张开量和接头侧向位移随弯矩呈线性变化,轴力对接缝张开量和接头侧向位移分别起抑制和促进作用;当M>1400 kN·m时,隧道接缝张开量和接头侧向位移随弯矩呈非线性变化,轴力对接缝张开和接头侧向位移起抑制作用;接缝面交错处塑性应变和损伤值随弯矩增加而大幅度增大,同时轴力对其发展有抑制作用。综上,这种新型接头结构整体力学性能良好,在浅埋矩形隧道中具有较好的应用前景。

With the wide application of rectangular prefabricated tunnel in urban traffic,the design and performance research of its joint have attracted much attention.Therefore,a new type of staggered tenon joint for rectangular tunnel is designed in this study.In order to investigate its mechanical properties,the variation laws of joint opening,lateral displacement,stress and strain,strain and damage characteristics at the intersection of joint surface under the combined action of non axial force and bending moment are analyzed by numerical simulation method.The results show that whenM≤1400 kN·m,the joint opening and joint lateral displacement change linearly with the bending moment,and the axial force inhibits and promotes the joint opening and joint lateral displacement respectively.WhenM>1400 kN·m,the tunnel joint opening and joint lateral displacement change nonlinearly with the bending moment,and the axial force inhibits the joint opening and joint lateral displacement.The plastic strain and damage value at the intersection of joint surfaces increase greatly with the increase of bending moment,and the axial force can inhibit its development.In conclusion,this new joint structure has good overall mechanical properties and has a good application prospect in shallow buried rectangular tunnel.