装配式空心板铰缝界面抗剪性能试验与数值模拟

发布时间：2018-01-13 17:13

本文关键词：装配式空心板铰缝界面抗剪性能试验与数值模拟　出处：《公路交通科技》2017年06期 　论文类型：期刊论文

【摘要】：为了掌握空心板铰缝新旧混凝土界面抗剪性能,并为新旧混凝土界面抗剪数值模拟提供参考,提出了铰缝新旧混凝土界面黏结的数值模拟方法以及界面黏结参数的合理取值。首先,结合国内外新旧混凝土抗剪性能试验研究方法,根据空心板铰缝的结构与受力形式,选择推出试验对空心板铰缝新旧混凝土界面破坏机理与抗剪性能进行了研究,推出试验共3组试件,每组试件由左、中、右3块试件组成,按1∶2的比例进行缩尺设计。在总结新旧混凝土界面受力性能的数值模拟方法基础上,提出了数值模拟空心板铰缝推出试验所采用的单元、本构关系和结合面的黏结强度,并对黏结滑移刚度及最终滑移值与峰值应力对应的滑移值的比值进行了分析,最后用推出试验结果验证该数值模拟方法的正确性。研究表明,当铰缝推出试验达到极限强度时,试件将沿铰缝新旧混凝土界面发生脆性破坏,平均抗剪强度为1.1 MPa,以平均剪应力等于0.5 MPa为界限,平均剪应力-滑移曲线近似由直线的弹性阶段和曲线的弹塑性阶段组成;数值模拟过程中铰缝混凝土本构关系采用损伤塑性模型,钢筋本构关系采用理想弹塑性模型,新旧混凝土结合面采用面面接触技术模拟,其中黏结滑移刚度取5 MPa/mm,最终滑移值与峰值应力对应的滑移值之比为2,该方法可获得较好效果。
[Abstract]:In order to master the shear behavior of the new and old concrete interface of the joint of hollow slab, and provide reference for the numerical simulation of the interface shear resistance of the new and old concrete. The numerical simulation method of new and old concrete interface bonding and the reasonable value of interface bonding parameters are put forward. Firstly, combined with the domestic and foreign new and old concrete shear performance test research methods. According to the structure and force form of the hinge joint of hollow slab, the failure mechanism and shear behavior of the new and old concrete interface of the joint of hollow slab hinge were studied by means of launch test, and three groups of specimens were presented, each group of specimens being left and middle. On the basis of summing up the numerical simulation method of the new and old concrete interface mechanical properties, the element used in the numerical simulation test of the hinged joint of hollow slab is put forward in this paper, which is based on the composition of the right 3 specimens and the scale design of the scale according to the ratio of 1: 2. The constitutive relation and bonding strength of the bonding surface are analyzed. The slip stiffness of the bond and the ratio of the final slip value to the slip value corresponding to the peak stress are analyzed. Finally, the correctness of the numerical simulation method is verified by the deductive test results. The results show that when the ultimate strength of the joint is reached, the brittle failure will occur along the interface of the new and old concrete joints. The average shear strength is 1. 1 MPA, and the average shear stress is equal to 0. 5 MPa. The average shear stress-slip curve is approximately composed of the elastic phase of the straight line and the elastoplastic phase of the curve. In the process of numerical simulation, damage plastic model is used for constitutive relation of hinged joint concrete, ideal elastoplastic model is used for constitutive relation of steel bar, and face to face contact technique is used to simulate new and old concrete joint surface. The slip stiffness of the bond is 5 MPA / mm and the ratio of the final slip value to the peak stress is 2. This method can obtain good results.
【作者单位】：福州大学土木工程学院;
【基金】：国家自然科学基金项目(51478120)
【分类号】：U441
【正文快照】： 0引言由于装配式空心板铰缝本身构造上的缺陷,经常出现一些病害,铰缝病害发展到一定程度会导致单板受力现象。单板受力危害很大,不但可以引起主梁病害,还可引起桥梁附属设施的病害,比如造成铺装层反射裂缝,形成桥面错台等,最终影响到桥梁的适用性和耐久性,甚至危及行车的安全

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