摘要
在分析总结现有试验结果和已有混凝土尺寸效应模型的基础上,认为影响全级配和湿筛混凝土强度的主要因素是控制性裂纹的长度,并从脆性材料细观破坏机理出发,分析了混凝土在轴拉、劈拉和轴压荷载下的破坏模式,得到了不同形式荷载下的混凝土内控制性裂纹长度,研究了最大骨料粒径对混凝土强度的影响规律。研究表明,随着最大骨料粒径的增加,混凝土内控制性裂纹尺寸逐渐增大,因此混凝土的强度随之降低。同时,全级配和湿筛混凝土强度比值以轴拉最小,劈拉强度次之,抗压强度最大。
After concluding the existed experimental results and size effect model of concrete,the main difference between the tensile and compressive strength of full-grade and wet-sieving concrete is assumed here which is the dominant crack size.At the same time,by analyzing the crack propagation process of concrete under the axial tension,splitting tension and axial compression,the dominant crack size in concrete is determined based on the microscopic failure mechanism of concrete,and the influence of maximum aggregate size on concrete strength is then analyzed.It is showed that with the increasing of maximum aggregate size,the dominant crack size in concrete is increased too,which would finally reduce the concrete strength.Meanwhile,the ratio of full-grade and wet-sieving concrete strength is lowest in the axial tension,while,successively in splitting tension and axial compression.
出处
《水利与建筑工程学报》
2011年第5期10-14,59,共6页
Journal of Water Resources and Architectural Engineering
基金
国家自然科学基金资助项目(50809079)
关键词
水工混凝土
全级配
强度
抗拉
抗压
hydraulic concrete
full-grade
strength
tensile resistance
compressive resistance
作者简介
郑丹（1979-），男（汉族），重庆人，博士，副教授，主要从事混凝土材料性能研究。
