分片预制装配式管廊管片接头力学性能试验研究

摘要

The deformation and bearing capacity of the overall structure are directly affected by mechanical properties for segment joints of split type precast pipe gallery.Compared with tunnel segment joint,bending stiffness and shear strength values of prefabricated municipal tunnel joint are lack of mature theoretical basis.Based on split type prefabricated municipal tunnel design in Chengdu fivephase Shulong comprehensive pipe gallery project and segment joint model test,this paper conducted a thorough study on its mechanical properties.The test results show that under the same axial force,eccentricity greater joint's bending stiffness is small.With the increase of axial force,there is a trend of decreasing in bending stiffness difference under different eccentricity.When ultra high performance concrete (UHPC) is adopted,the bending stiffness and shear strength are obviously larger than those of C50 concrete joints,the increase is 1.5 ～2.0 times.The test results can be referred to the similar structural design calculation.%分片预制装配式管廊管片接头力学性能直接影响管廊整体结构的变形和承载能力,而相较于隧道衬砌管片接头,分片预制装配式管廊管片接头的抗弯刚度与抗剪强度相关取值缺乏成熟理论依据.基于成都蜀龙五期综合管廊工程项目的分片预制装配式管廊设计,通过管片接头足尺模型试验,对其力学性能进行了充分研究.试验结果表明:同等轴力下,偏心距越大管片接头抗弯刚度越小,且随轴力的增大不同偏心距管片接头抗弯刚度差距有变小的趋势;当管片接头采用超高性能混凝土(UHPC)时,抗弯刚度和抗剪强度均明显大于C50普通混凝土管片接头,同等加载条件下增幅为1.5 ～2.0倍.试验结果可供类似分片预制装配式管廊的结构设计计算参考.