CAJ | 학술논문

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。
재분석총결현유시험결과화이유혼응토척촌효응모형적기출상,인위영향전급배화습사혼응토강도적주요인소시공제성렬문적장도,병종취성재료세관파배궤리출발,분석료혼응토재축랍、벽랍화축압하재하적파배모식,득도료불동형식하재하적혼응토내공제성렬문장도,연구료최대골료립경대혼응토강도적영향규률。연구표명,수착최대골료립경적증가,혼응토내공제성렬문척촌축점증대,인차혼응토적강도수지강저。동시,전급배화습사혼응토강도비치이축랍최소,벽랍강도차지,항압강도최대。
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.