大型综合管廊十字型交叉口结构内力分析

Structural Internal Force Analysis of Cross-Shaped Intersections of Large Utility Tunnel

以海口市某地下四层综合管廊交叉口为例,通过三维有限元分析其空间整体受力状态。通过三维结果与二维结果进行对比,得出主要结论是:底板梁与底板之间变形协调效应显著,底板梁不能完全充当底板的固端支座;交叉口中板不仅承担板上荷载,还参与结构整体受力;顶板与侧壁交界支座按刚度进行内力分配,将其简化为简支或固端与实际情况不符。通过分析对比,指出三维整体计算对复杂地下结构内力分析的有效性、合理性,对类似工程有一定借鉴意义。

Taking the intersection of a four floor underground utility tunnel in Haikou as an example,through the 3D finite element analysis,the overall stress state of the space is clearly obtained.Through the comparison between the 3D&the 2D results,the main conclusions are as follows:the deformation coordination effect between the floor beam and the floor is significant,and the floor beam cannot completely act as the fixed end support of the floor;the middle slab of intersection not only bears the load on the slab,but also participates in the overall stress of the structure;the internal force of the support at the junction of the roof&the side wall is distributed according to the stiffness,and it is not consistent with the actual situation to simplify it as simply supported or fixed end.Through the comparative analysis,it points out the validity&rationality of the 3D integral calculation for the internal force analysis of complex underground structures,which has a certain reference significance for similar projects.