摘要
利用直径30 mm的分离式霍普金森压杆,对不同弹速下砂岩试样进行巴西圆盘劈裂实验,研究砂岩在高应变率下的动态抗拉强度及试样的破坏模式,得到了砂岩的动态抗拉强度随着应变率的提高而增加。其中,在应变率小于316/s时,动态抗拉强度随着应变率的增加而大幅增大,在应变率高于316/s时,动态抗拉强度随着应变率的增加而平缓的增加。考虑了压杆撞击速度及试样尺寸对试样的破坏时刻、应变率的影响,通过试样表面贴应变片观测发现试样是由中心向两端发展的起裂顺序。同时,利用ANSYS-LYDYNA有限元对巴西圆盘试样的动态应力分布进行数值模拟,验证了动态劈裂拉伸实验的有效性。
To study the dynamic tensile strength and failure modes of sandstone samples under high strain rate, the Brazilian disk split experiment of sandstone samples were performed under different projectile velocity by using the split Hopkinson pressure bar with a diameter of 35mm. The results showed that dynamic tensile strength of sandstone increased with the strain rate increasing, which increased sharply when the strain rate was less than 316/s, while increased slowly above 316/s. By considering the influence of pressure bar impact velocity and specimen size on failure time and strain rate, the initial cracking propagated from center to the ends. Meanwhile, the validity of dynamic splitting tensile experiments was verified by using ANSYS-LYDYNA finite element to simulate dynamic stress distribution of Brazilian disc specimen.
出处
《爆破》
CSCD
北大核心
2014年第2期8-13,71,共7页
Blasting
基金
国家自然科学基金资助项目(51174005)
霍英东青年教师基金基础性研究资助课题(121050)
重庆大学西南资源开发及环境灾害控制工程教育部重点实验室访问学者基金
关键词
巴西圆盘
劈裂
动态抗拉强度
应变率
破坏时刻
破坏模式
Brazilian disk
split
dynamic tensile strength
strain rate
failure time
failure modes
