期刊文献+

新浇混凝土爆破振动损伤累积机制试验研究 被引量:6

Experimental research on blasting vibration damage accumulation mechanism of fresh concrete
下载PDF
导出
摘要 为揭示新浇混凝土爆破振动损伤累积机制,设计并开展新浇混凝土爆破振动损伤累积模拟试验。首先测量超声波波速,并计算损伤值;然后利用试验结果和损伤断裂力学原理,分析新浇混凝土振动损伤累积规律与机制。结果表明:受振混凝土超声波速变化经历快速增长、缓慢增长、降低和稳定4个阶段;损伤值在第一阶段快速减小,进入第2阶段后损伤劣化效应显现,损伤值随着振动次数的增加先快速增加、后缓慢增加;受振混凝土中的峰值波速和稳定波速均低于基准混凝土的相应波速,高强混凝土损伤累积劣化效应较普通混凝土明显。新浇混凝土振动损伤累积是原生微裂纹尖端局部损伤变形、微裂纹和细观裂纹扩展的结果。 In order to reveal the blasting vibration damage accumulation mechanism of fresh concrete,the authors designed and carried out blasting vibration damage accumulation simulation experiments,tested the ultrasonic wave velocity and calculated the damage value. The experimental results show that the ultrasonic wave velocity change experiences four stages under repeated frequently blasting vibration load,they are a rapid growth stage,a slow growth stage,a damage degradation lower stage and a stable stage,that the ratio of reducing ultrasonic wave velocity decrease rapidly in the first stage,blasting vibration promotes the development of fresh concrete strength,but the ratio of reducing ultrasonic wave velocity begins to increase sustainably from the second stage,and the damage deterioration effect appears,the blasting vibration damage increases rapidly first,then increases slowly and tends to be stable with the increase of the vibration times,that both the peak wave velocity and steady ultrasonic wave velocity are lower than that those in the datum concrete,and the damage degradation of high strength concrete is more obvious than that of the ordinary concrete,and that the blasting vibration damage accumulation of fresh concrete is the results of native micro crack tip local damage deformation and the micro cracks and mesoscopic crack propagation.
出处 《中国安全科学学报》 CAS CSCD 北大核心 2017年第9期69-73,共5页 China Safety Science Journal
基金 国家自然科学基金资助(11542019 51504082) 河南省基础与前沿技术研究项目(162300410032) 河南理工大学骨干教师项目 河南理工大学博士基金资助(B2013-062)
关键词 爆破振动 新浇混凝土 损伤累积 超声波波速 模拟试验 blasting vibration fresh concrete damage accumulation ultrasonic wave velocity simulation experiment
  • 相关文献

参考文献12

二级参考文献121

共引文献239

同被引文献58

引证文献6

二级引证文献17

相关作者

内容加载中请稍等...

相关机构

内容加载中请稍等...

相关主题

内容加载中请稍等...

浏览历史

内容加载中请稍等...
;
使用帮助 返回顶部