摘要
以扁平试块强度的形状效应问题为背景,通过理论分析和试验数据,反算了不同等级混凝土发生剪切破坏时的破裂面方位角,并给出了边界理想强约束时不同高径比试件中的最危险破裂面,将该破裂面方位角和最危险破裂面进行了对比,定量分析了形状效应的产生机理,结果表明:扁平试块的破裂区为左右对称的崩解区和上下对称的刺入区;可能的破裂面方位角被限制在了26.6°及其以下,不存在发生剪切破坏所必须的试块高度,最终的破坏以压缩为主;混凝土的抗压强度要大于抗剪强度,故扁平试块的抗压强度比正常高宽比试块要大。
Taking the shape effect of flat test block strength as the background,the fracture surface azimuth of concrete of different grades subjected to shear failure was calculated based on the theoretical analysis and experimental results.Then the most dangerous rupture surfaces were given under strong boundary constraint in different height to diameter specimen,meanwhile,the fracture azimuths were compared with the most dangerous fracture surfaces.In addition,the mechanism of shape effect was quantitatively analyzed,and the results showed that:The rupture zones of flat test block were consisted by two parts,one is disintegration zone of bilateral symmetry,and another is stabbed zone of symmetry up and down;The possible fracture surface azimuth was limited to 26.6 degrees and below,so there is no specimen height necessary for shear failure,and the ultimate destruction was dominated by compression;Considering the compressive strength of concrete is greater than the shear strength,therefore,the compressive strength measured by the flat test block is larger than the test blocks with normal height and width.
出处
《内蒙古工业大学学报（自然科学版）》
2017年第5期385-390,共6页
Journal of Inner Mongolia University of Technology：Natural Science Edition
基金
国家自然基金资助项目(51569001
51369001)
关键词
扁平试块
边界约束
应力集中
形状效应
破裂面方位角
Flat test block
Boundary constraint
Stress concentration
Shape effect
Fracture surface azimuth
