自密实轻骨料混凝土断裂全过程分析  

Analysis of crack propagation in self-compacting lightweight concrete

作　　者：吴熙[1] 范兴朗[2] 吴智敏[1] 

机构地区：[1]大连理工大学海岸及近海工程国家重点实验室,辽宁大连116024 [2]浙江工业大学建筑工程学院,浙江杭州310014

出　　处：《水利水电科技进展》2014年第6期36-39,44,共5页Advances in Science and Technology of Water Resources

摘　　要：为研究自密实轻骨料混凝土的断裂特性,引入以起裂断裂韧度为参数的裂缝扩展准则,采用数值方法分析了自密实轻骨料混凝土三点弯曲梁裂缝扩展的全过程,得到了不同缝高比的自密实轻骨料混凝土梁在三点荷载下的荷载-裂缝口张开位移曲线,并根据裂缝扩展准则,计算了自密实轻骨料混凝土的断裂过程区长度和裂缝扩展阻力曲线。结果表明:试验和计算的荷载-裂缝口张开位移曲线吻合良好,验证了裂缝扩展准则的正确性;试验断裂过程区长度随着裂缝增长先增大,达到完整断裂过程区长度后减小;自密实轻骨料混凝土的裂缝阻力随着裂缝长度增加而不断增大,初始缝高比对裂缝扩展阻力曲线数值和形状的影响并不明显。In order to study the fracture characteristics of self-compacting lightweight concrete （ SCLC ） , the crack propagation criterion, which uses initial cracking toughness as the main parameter is used to numerically analyze the complete process of crack propagation in SCLC three-point bending beam. The criterion was verified by the reasonable agreement between calculated and experimental load-crack mouth opening displacement. According to the criterion, the length of fracture process zone （ FPZ） and KR-curves of SCLC can be obtained. The results show that FPZ length increases with the crack extension and decreases after the full FPZ length. KR of SCLC specimens increases as the crack length increases and KR-curves of SCLC specimens, with different initial crack length ratio, shows insignificant differences in terms of shape and value.

关 键 词：自密实轻骨料混凝土 三点弯曲梁 断裂过程区 裂缝扩展阻力曲线 

分 类 号：TU528.2[建筑科学—建筑技术科学]