CAJ | 학술논문

利用大杆径分离式霍金森压杆(SHPB)试验装置，对1、3、7、14、28 d这5组龄期下的混凝土进行冲击压缩试验，研究早龄期混凝土(C 20)在不同冲击条件下的力学特性。结果表明：龄期7 d以前，各龄期50%临界入射能的冲击有助于提高混凝土的强度和弹性模量；龄期7 d以后，无论是75%还是50%临界入射能的冲击，都会使混凝土的强度和弹性模量降低；在单次冲击条件下，混凝土的变形能力和单位体积吸收能与龄期呈对数关系增长；在多个龄期冲击条件下，混凝土的变形能力和单位体积吸收能都受到不同程度的影响，其中单位体积吸收能下降了50%。
이용대간경분리식곽금삼압간(SHPB)시험장치，대1、3、7、14、28 d저5조령기하적혼응토진행충격압축시험，연구조령기혼응토(C 20)재불동충격조건하적역학특성。결과표명：령기7 d이전，각령기50%림계입사능적충격유조우제고혼응토적강도화탄성모량；령기7 d이후，무론시75%환시50%림계입사능적충격，도회사혼응토적강도화탄성모량강저；재단차충격조건하，혼응토적변형능력화단위체적흡수능여령기정대수관계증장；재다개령기충격조건하，혼응토적변형능력화단위체적흡수능도수도불동정도적영향，기중단위체적흡수능하강료50%。
In order to understand the mechanical properties of early age concrete(C 20 ) under different loading conditions systematically, the impact compression tests of five early age concrete were conducted with a large diameter split Hopkinson pressure bar. The results show that, the dynamic strength and elastic modulus of concrete are improved under the impact level of 50%or 75%corresponding critical incident energy before age of 7 d, while they would decrease if concrete suffered any impact after age of 7 d. The growth trend of deformation capacity and unit volume absorption energy of concrete with age can be presented with a logarithmic function under single impact. While the deformation capacity and unit volume absorption energy of concrete are affected when the concrete suffers impact at multiple ages, and the later is even declined by 50%.