预制槽型拼装综合管廊横向接头受弯性能分析

Bending Performance Analysis on Transverse Joint of Precast Utility Tunnel with Groove-shaped Elements

预制槽型拼装综合管廊在横向由.上下两个槽型预制构件通过预应力筋连接而成。为研究其横向接头的受弯性能,建立了考虑拼缝构造影响的横向接头受弯性能有限元分析模型,通过与试验结果的对比分析,验证了该分析模型的合理性。在此基础上,通过改变预应力大小,分析了拼缝界面压力大小对接头受弯性能的影响规律。结果表明:拼缝界面压力对接头受弯破坏形态影响不大,试件均发生接头受弯破坏,破坏时拼缝两侧的预制混凝土板发生较大的相对转动;拼缝界面压力对接头受弯承载力和转动刚度影响显著,两者均随界面压力的增大而增加;不同拼缝界面压力下接头的弯矩-转角曲线形态相似,均呈三折线,预应力筋屈服之后,拼缝面的转动刚度明显下降。最后建立了接头受弯承载力与拼缝界面压力以及转动刚度与拼缝界面压力的拟合曲线,可为预制槽型拼装综合管廊的结构分析提供依据。

The precast utility tunnel with groove-shaped elements consists of a pair of prefabricated groove members connected by prestressing tendons transversely.In this paper,a finite element model was established to investigate the influence of the joint surface configuration on the bending performance of the transverse joint.This model was validated by comparing it with test results.Then,on this basis,the influence of the joint interface pressure on the bending performance of the joint was analyzed by changing the prestress values.The results show that:the joint interface pressure has little effect on the bending failure mode of the joints,the joints all exhibit flexural failure,and the precast concrete slabs on both sides of the joints undergo large relative rotations during failure;the joint interface pressure has a significant effect on the bending bearing capacity and rotational stiffness of the joint,both of which increase with the increase of the interface pressure;The bending moment-rotation curves of the joints under different interface pressures are similar in shape,which are all three-fold lines.After the prestressed tendons yield,the rotational stiffness of the interface decreases significantly.Finally,the fitting curves of the joint interface compression relating to the flexural bearing capacity and rotational stiffness and were established.This study could provide references for the design of a precast utility tunnel with groove-shaped elements.