CAJ | 학술논문

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。
축향랍신시험시학정혼응토랍신단렬특성최직접적방법。이용중국수이수전과학연구원대형동태재료시험궤개전료전급배혼응토대시건적동태축랍시험연구。재시건여시험궤지간설치교접좌조건이소제랍신과정중부가만구적산생，병채취괄당조시강저랍신시험중편심적영향。장20개전급배혼응토대시건、23개습사혼응토소시건안요축일기분위3조진행시험。결과표명，혼응토축랍강도적골료효응화척촌효응십분현저，정태축랍강도교동태축랍강도수기영향경대；충격하재작용하，골료파배비례증가；축랍강도여겁한랍신치적솔민감성현저；축랍강도월저，기솔민감성월고；이항랍탄성모량적솔민감성교저。
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 ma?chine 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 tak?en 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 ef?fects 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 ef?fect increases greatly.