CAJ | 학술논문

对不同级配（二级配、三级配、四级配）的混凝土在不同应变速率下（10－5／s，10－4／s，10－3／s，10－2／s）下进行了劈拉试验。对混凝土劈拉强度及轴向应变进行了深入分析，并利用实时采集的声发射数据分析了大体积混凝土在劈拉破坏全过程中的能量释放特性及破坏规律。结果表明：随应变速率的增加混凝土劈拉强度呈增加的趋势，混凝土级配越高劈拉强度变化的奇异性越大；混凝土劈裂抗拉破坏过程不具有典型未裂阶段、裂缝阶段和破坏阶段的3阶段特征，加载前期产生的声发射信号较微弱，材料达到峰值应力时能量信号突然急剧上升；采集的声发射数据能较真实地反映混凝土劈拉破坏全过程。
대불동급배（이급배、삼급배、사급배）적혼응토재불동응변속솔하（10－5／s，10－4／s，10－3／s，10－2／s）하진행료벽랍시험。대혼응토벽랍강도급축향응변진행료심입분석，병이용실시채집적성발사수거분석료대체적혼응토재벽랍파배전과정중적능량석방특성급파배규률。결과표명：수응변속솔적증가혼응토벽랍강도정증가적추세，혼응토급배월고벽랍강도변화적기이성월대；혼응토벽렬항랍파배과정불구유전형미렬계단、렬봉계단화파배계단적3계단특정，가재전기산생적성발사신호교미약，재료체도봉치응력시능량신호돌연급극상승；채집적성발사수거능교진실지반영혼응토벽랍파배전과정。
Splitting tensile tests were conducted on concrete with different gradations (two gradations,three grada-tions,and four gradations)under different strain rates (10-5 /s,10-4 /s,10-3 /s,10-2 /s).The splitting tensile strength and axial strain of concrete were analyzed,and the energy release characteristics and damage regularity of mass concrete in the whole process of splitting tensile damage were researched through collected real-time acoustic emission data.Results show that with the strain rate increasing,the splitting tensile strength of concrete displays a trend of increasing.Singularity in the variation of splitting tensile strength is larger when the gradation of concrete is higher.The process of splitting tensile failure does not have the characteristics of a typical three-stage:stage without cracks,stage with cracks,and stage of failure.The acoustic emission signal is weak in the early stage of loading, but rises sharply when the material reaches peak stress.Acoustic emission data can truly reflect the process of con-crete splitting tensile failure.