螺栓连接板式拼装混凝土综合管廊受力性能分析

Analysis of the Structural Performance of Bolted Connected Precast Utility Tunnel

螺栓连接板式拼装混凝土综合管廊由底板、侧壁和顶板组成,其中侧壁通过底板预留螺栓钢筋连接。为研究该预制拼装方案综合管廊的受力性能,对其下部边节点及现浇对比试件开展了足尺低周反复荷载试验研究。在试验基础上,基于ABAQUS有限元分析软件建立板式拼装混凝土综合管廊下部边节点有限元分析模型,进一步开展腋角高度、轴压比对该拼装方案的力学性能影响分析。试验结果表明,在低周反复荷载作用下,预制和现浇试件均为侧壁受弯破坏,具体表现为侧壁端部受弯破坏;预制试件承载力比现浇试件低7%。有限元分析结果表明,腋角明显提升节点承载力,相较于无腋试件,当腋角高度为150mm时,模型正反向承载力分别提升4.5%和13.6%;当腋角高度为250mm时,试件正反向承载力分别提升12%和27%;轴压比对节点承载力影响较小,随着轴压比增大,模型由侧壁端部受弯破坏转变为底座端部受弯破坏。

The bolted connected precast utility tunnel consists of a bottom slab,sidewalls,and top slab,with the sidewalls connected to the bottom slab by pre-embedded bolt reinforcement.To investigate the structural performance of this precast utility tunnel,full-scale low-cycle tests were conducted on its lower edge nodes and compared with cast-in-place(CIP)specimens.Based on the test results,finite element analysis models of the lower edge nodes of the precast utility tunnel were established using finite element analysis software ABAQUS,further exploring the mechanical performance affected by the axillary angle height and axial compression ratio of this assembly scheme.The test results indicate that the failure mode of both prefabricated and CIP specimens is bending failure of the sidewalls,specifically manifested as bending failure at the end of the sidewalls;The bearing capacity of the prefabricated specimens is 7%lower than that of the CIP specimens.Finite element analysis results show that the axillary angle significantly enhances the node’s bearing capacity.Compared with the specimens without axillary angle,when the axillary angle height is 150mm,the model’s positive and negative bearing capacities increase by 45%and 136%,respectively;When the axillary angle height is 250mm,the positive and negative bearing capacities of the specimens increase by 12%and 27%,respectively.The axial compression ratio has a minor effect on the node’s bearing capacity.With the increase in axial compression ratio,the failure mode of the model changes from bending failure at the end of the sidewalls to bending failure at the end of the bottom slab.