CAJ | 학술논문

为了研究被动围压约束条件下早龄期混凝土动态力学性能,利用直径74 mm分离式霍普金森压杆进行试验。在不同加载气压钢质套筒被动约束条件下,测试7d龄期补偿收缩钢纤维混凝土试件轴向或径向的应力和应变变化趋势。结果表明：补偿收缩钢纤维混凝土材料在被动围压下,延性和抵抗破坏能力显著加强,试件轴向应力-时间历程曲线和轴向应力-应变曲线可知,整个加载过程分为三个阶段。第一阶段为弹性阶段,由于试件刚性所致,应力增幅快；第二阶段为弹塑性阶段,试件逐步压缩变形,应力增长缓慢,应变增幅大；第三阶段为试件塑性破坏阶段,应力直线下降；在0．6 MPa、0．7 MPa和0．8 MPa气压作用下,试样典型轴向应力峰值为无围压条件单轴压缩SHPB实验时的1．5￣1．8倍；试件破坏应变高达（23￣27)×10－3,是无围压SHPB试验试件破坏应变的4￣6倍；从试件破坏形态看,由于钢纤维掺入,试件仍保持较好的整体性,裂缝分布表征试件为压剪破坏。
위료연구피동위압약속조건하조령기혼응토동태역학성능,이용직경74 mm분리식곽보금삼압간진행시험。재불동가재기압강질투통피동약속조건하,측시7d령기보상수축강섬유혼응토시건축향혹경향적응력화응변변화추세。결과표명：보상수축강섬유혼응토재료재피동위압하,연성화저항파배능력현저가강,시건축향응력-시간역정곡선화축향응력-응변곡선가지,정개가재과정분위삼개계단。제일계단위탄성계단,유우시건강성소치,응력증폭쾌；제이계단위탄소성계단,시건축보압축변형,응력증장완만,응변증폭대；제삼계단위시건소성파배계단,응력직선하강；재0．6 MPa、0．7 MPa화0．8 MPa기압작용하,시양전형축향응력봉치위무위압조건단축압축SHPB실험시적1．5￣1．8배；시건파배응변고체（23￣27)×10－3,시무위압SHPB시험시건파배응변적4￣6배；종시건파배형태간,유우강섬유참입,시건잉보지교호적정체성,렬봉분포표정시건위압전파배。
In order to research the dynamic mechanical properties of early age concrete under the passive confi-ning constraint conditions, experiments by using 74 mm diameter SHPB were maken which aim at testing the axial or radial stress and strain variation trend of 7 d age shrinkage compensation of steel fiber reinforced concrete ( SCS-FRC) under different load pressure steel sleeve passive constraints. Results show that under the passive confining pressure, compensating shrinkage steel fiber concrete material′s ductility and the ability of resisting destruction strengthen dramatically. The axials stress-time history curve of the specimen and the axial stress-strain curve reveal that the whole loading processes can be divided into three stages. Namely, the first stage is the elastic stage, stress increase fast due to rigidity of specimen. The second stage is the elastic-plastic stage in which specimens com-pressed into deformation gradually, the stress increase slowly, but the amplification of strain increase dramatically. The third stage is the plastic failure stage that the stress declines linearly. Under the pressure of 0. 6 MPa, 0. 7 MPa and 0. 8 MPa, the typical axial stress peak value of specimens is 1. 5 to 1. 8 times of single axial compression SHPB experiment without confining pressure condition. Specimen failure strain up to (23￣27) × 10 -3, is no confining pressure SHPB test specimen failure strain of 4 ￣ 6 times. Besides, in terms of the specimen failure pattern, it can see that when adding steel fiber, specimen still keep good integrity and the crack distribution characterization of specimens is compressive shear failure.