全级配混凝土动态轴拉试验  

Dynamic axial tension test on the fully-graded concrete

作　　者：张艳红[1] 胡晓[1] 杨陈[1] 李春雷[1] 朱红东[1] 焦健[1] 

机构地区：[1]中国水利水电科学研究院工程抗震研究中心,北京100048

出　　处：《水利学报》2014年第6期720-727,共8页Journal of Hydraulic Engineering

摘　　要：轴向拉伸试验是确定混凝土拉伸断裂特性最直接的方法。利用中国水利水电科学研究院大型动态材料试验机开展了全级配混凝土大试件的动态轴拉试验研究。在试件与试验机之间设置铰接座组件以消除拉伸过程中附加弯矩的产生,并采取适当措施降低拉伸试验中偏心的影响。将20个全级配混凝土大试件、23个湿筛混凝土小试件按浇筑日期分为3组进行试验。结果表明,混凝土轴拉强度的骨料效应和尺寸效应十分显著,静态轴拉强度较动态轴拉强度受其影响更大;冲击荷载作用下,骨料破坏比例增加;轴拉强度与极限拉伸值的率敏感性显著;轴拉强度越低,其率敏感性越高;而抗拉弹性模量的率敏感性较低。Axial tension test is the most direct way to determine the tensile properties of concrete. In this paper, dynamic axial tension test of fully-graded concrete is firstly carried out on the material testing machine in IWHR, China. The hinge components are set between the specimen and the testing machine to eliminate the influence of additional bending moment during tension,and appropriate measures are also taken to mitigate the effects of eccentricity in the test. Twenty fully-graded large specimens and twenty-three wet-sieving small specimens are divided into three groups according to their casting date. The results show that the aggregate effect and the size effect of concrete axial tensile strength are significant, and their effects on the static axial tensile strength are greater than those on the dynamic axial tensile strength. Under impact loads, aggregate damage increases. Rate effects of axial tensile strength and limit tensile strain are greater than that of axial tensile elastic modulus. With decreasing of the axial tensile strength, the rate effect increases greatly.

关 键 词：轴向拉伸 混凝土 全级配大试件 湿筛小试件 加载速率 

分 类 号：TV431[水利工程—水工结构工程]