CAJ | 학술논문

采用电液伺服大型多功能动静三轴仪对不同应变速率（10－5／s，10－4／s，10－3／s，10－2／s）下不同尺寸（150，300，450 mm）的立方体混凝土试件进行单轴动态压缩试验，对不同尺寸混凝土动态物理力学参数（峰值应力、峰值应变）、实验破坏机理及峰后应变软化进行分析，并对不同尺寸混凝土在不同的应变速率下的软化性能进行研究。研究结果表明：混凝土峰值应力、峰值应变都随试件尺寸增大而降低；混凝土强度随着应变速率的增加而增加；峰值应变后，随着试件尺寸增加，应力－应变曲线斜率绝对值增加，延性减小；试件尺寸为150 mm 混凝土的软化现象随着应变速率的提高而愈加明显，且软化程度呈增加趋势，试件尺寸为300 mm 和450 mm 混凝土的软化现象随着应变速率的提高而变得越来越弱化，当应变速率增加到一定值时，软化现象又变得明显；在同一应变速率下，随试件尺寸的增加软化现象越来越明显。
채용전액사복대형다공능동정삼축의대불동응변속솔（10－5／s，10－4／s，10－3／s，10－2／s）하불동척촌（150，300，450 mm）적립방체혼응토시건진행단축동태압축시험，대불동척촌혼응토동태물리역학삼수（봉치응력、봉치응변）、실험파배궤리급봉후응변연화진행분석，병대불동척촌혼응토재불동적응변속솔하적연화성능진행연구。연구결과표명：혼응토봉치응력、봉치응변도수시건척촌증대이강저；혼응토강도수착응변속솔적증가이증가；봉치응변후，수착시건척촌증가，응력－응변곡선사솔절대치증가，연성감소；시건척촌위150 mm 혼응토적연화현상수착응변속솔적제고이유가명현，차연화정도정증가추세，시건척촌위300 mm 화450 mm 혼응토적연화현상수착응변속솔적제고이변득월래월약화，당응변속솔증가도일정치시，연화현상우변득명현；재동일응변속솔하，수시건척촌적증가연화현상월래월명현。
The physical and mechanical parameters (peak stress,peak strain),failure mechanism and post-peak strain softening (softening performance)of concrete with different sizes under different strain rates were researched through uniaxial dynamic compression test.The test was conducted on cubic concrete specimens of different sizes (1 50mm,300mm,450mm)at different strain rates (1 0 -5 /s,1 0 -4 /s,1 0 -3 /s,1 0 -2 /s)by large multi-functional electro-hydraulic servo static triaxial machine.Results showed that concrete’s peak stress and peak strain both re-duced with the increase of specimen size;concrete strength increased with the increase of strain rate;after the peak strain occurred,the absolute value of the stress-strain curve slope increased whereas the ductility reduced as the specimen size increases.For the specimen size of 1 50mm,concrete softening strengthened with increasing strain rate,and the softening degree increased;while for the specimen size of 300mm and 450mm,the softening weak-ened when strain rate increased,but when the strain rate increased to a certain value,the softening became appar-ent.At the same strain rate,the softening was increasingly apparent with the increase of specimen size.