大断面矩形盾构隧道管片接头极限抗弯承载力试验

发布时间：2018-03-22 14:52

  本文选题：盾构隧道　切入点：接头性能　出处：《中国公路学报》2017年08期 　论文类型：期刊论文

【摘要】：为了研究大断面矩形盾构隧道管片接头结构的力学性能及其极限承载能力和极限破坏状态,进行了该管片接头的极限抗弯承载力试验。试验在同济大学自主研发的盾构隧道管片接头试验加载系统中进行,采用Datataker数据采集系统记录了接头试件在荷载作用下的力学性能变化过程,同时采集并记录了该接头的破坏过程和最终破坏形态。通过分析管片接缝张角、接头处挠度以及双排螺栓应力随接头处弯矩荷载的变化,对该管片接头结构力学性能变化及破坏全过程进行研究,并将其分为3个阶段:弹性变化阶段(弯矩小于450kN·m)、塑性发展阶段(弯矩为450~800kN·m)、屈服破坏阶段(弯矩大于800kN·m)。试验结果表明:正弯矩荷载下该断面形式的大断面矩形盾构隧道管片接头屈服弯矩为800kN·m,极限抗弯承载力为884kN·m,均远大于该管片接头设计荷载(534kN·m),意味着试验的大断面矩形盾构隧道管片接头可满足抗弯设计的要求,并为类似工程提供参考。管片接头试件的最终破坏形态表明,除了传统圆形盾构隧道管片接头试验中常见的接缝混凝土受压屈服破坏、接头螺栓受拉屈服破坏以外,所研究的大断面矩形盾构隧道纵缝接头出现了新的破坏形态,即接头盒断裂和锚固失效。
[Abstract]:In order to study the mechanical properties, ultimate bearing capacity and ultimate failure state of segmental joint structure of large section rectangular shield tunnel, The ultimate bending bearing capacity of the segment joint was tested. The test was carried out in the shield tunnel segment joint test loading system independently developed by Tongji University. Datataker data acquisition system was used to record the change of mechanical properties of the joint specimen under load, and the failure process and final failure form of the joint were collected and recorded. The deflection at the joint and the stress of the double row bolts vary with the bending moment load at the joint. The mechanical properties of the segment joint and the whole process of failure are studied. It can be divided into three stages: elastic change stage (moment less than 450kN MN), plastic development stage (moment is 450~800kN mJ, yield failure stage (moment is greater than 800kN mu). The test results show that the rectangular shield with large cross section under positive moment load is a large section of rectangular shield. The yield moment of tunnel segment joint is 800kN m, and the ultimate flexural capacity is 884kN m, which is much larger than the design load of this segment joint (534kN / m), which means that the large section rectangular shield tunnel segment joint can meet the requirements of bending design. The ultimate failure pattern of segment joint specimen shows that, except for the common joint joint test of circular shield tunnel, joint concrete is subjected to compressive yield failure and joint bolt is subjected to tensile yield failure. The longitudinal joint of the large section rectangular shield tunnel has appeared a new failure mode, that is, the fracture of joint box and the failure of Anchorage.
【作者单位】： 同济大学地下建筑与工程系;同济大学岩土及地下工程教育部重点实验室;上海市城市建设设计研究总院(集团)有限公司;
【基金】：国家自然科学基金项目(51378388) 上海市科委科研计划项目(15XD1522500,16DZ1201701)
【分类号】：U455.43
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本文编号：1649142