预制拼装综合管廊承插式接头剪切力学性能研究

Shear Mechanical Properties of Bell and Spigot Joint of Precast Utility Tunnel

为研究预制拼装综合管廊节段剪切工况下承插式接头力学性能,本文建立地下预制拼装综合管廊土三维数值模型,通过对管廊节段施加位移荷载模拟顺剪与逆剪,分析承插式接头应力分布规律,最后建立沉降量与接头剪力的关系,得到接头极限承载力与极限错台位移。结果表明:预制拼装综合管廊节段剪切造成管廊接头内侧受压外侧受拉,接头插口端应力分布在竖向侧壁,承口端主要由顶底板两侧受力,承插式接头最大主应力集中在承口端侧壁顶部外侧1 m处及插口端的底板;管廊节段顺剪接头剪力随沉降增大而减小,逆剪接头剪力随沉降增大而增大,承插式接头顺剪与逆剪工况极限剪应力分别为407 kN和512 kN左右,研究结果可为预制拼装综合管廊安全运营提供科学依据。

To obtain mechanical properties of bell and spigot joint under precast utility tunnel is sheared,a three-dimensional numerical model for soil and underground utility tunnel was established in this paper,the longitudinal uneven settlement of the utility tunnel segment was simulated by applying displacement,and the stress distribution law of the bell and spigot joint was obtained.Finally,the relationship between segmental settlement and joint shear loading capacity was established,and the ultimate settlement displacement of precast utility tunnel was obtained.The results show that:When the precast utility tunnel segment is sheared,the medial compression and lateral tension of the utility tunnel segment are caused.The stress at the spigot joint is distributed in the vertical side wall.The stress distribution in the bell roof and floor,the bearing end is mainly subjected to force on both sides of the top and bottom plate.The maximum principal stress of the bell joint is concentrated at the upper 1 m of the side wall,spigot the stress is concentrated in the bottom.The shear stress increases with the settlement increase under the parallel shear condition,while that decreases with the increase of displacement under reverse shear condition.the ultimate shear stress of the bell and spigot joint is 407 kN and 512 kN,The research results provide a scientific basis for the utility tunnel project engineering safe operation.