隧道衬砌混凝土爆破损伤累积规律试验研究

民爆库

摘要：  
针对隧道衬砌混凝土爆破振动损伤累积问题,设计混凝土爆破损伤累积试验,对试块进行超声波波速测试并计算损伤值,拟合累积损伤值与爆破循环次数比之间的函数.试验结果表明,爆破振动损伤随着爆破作用次数的增加而持续增加,混凝土爆破振动累积损伤与爆破循环次数比之间存在三次多项式函数关系,爆破振动损伤累积经历了初期缓慢增长、中期快速增长和后期突变增长三个阶段.震动区测点在多次爆破振动荷载作用下,首先引起混凝土内部原生裂纹尖端局部损伤变形,随后微裂纹扩展形成细观裂纹,最后细观裂纹扩展贯通直至形成宏观裂缝,混凝土试块强度大幅度下降,累积损伤进入突变阶段后混凝土在较低损伤值条件下即可发生突然断裂破坏.
Abstract：  
To address blasting vibration induced damage accumulation of tunnel lining concrete,a test on blas-ting induced damage accumulation of concrete was designed.A test of ultrasonic velocity was held on the speci-men and the damage value was calculated,to fit the function between cumulative damage value and blasting cy-cle index ratio.The experimental results show that the blasting vibration damage continues to increase with the increase of the blasting times.A cubic polynomial function relationship exists between the cumulative damage value and blasting cycle index ratio.The blasting vibration induced damage accumulation has experienced three stages,including the slow growth in the early stage,rapid growth stage and abrupt growth stage.The blasting vibration causes damage and deformation at the original micro crack tip inside the concrete first,and then the micro crack extends to form mesoscopic cracks.Finally,the mesoscopic cracks extend and link each other until the macroscopic crack is formed.The strength of the concrete specimen drops dramatically with the increase of the blasting times,and abrupt fracture of concrete block can occur under the condition of lower damage value.
doi：  10.3969/j.issn.1001-8360.2018.03.020  
作者：  褚怀保  杨小林  叶红宇  梁为民  余永强  魏海霞   
Author：  CHU Huaibao    YANG Xiaolin    YE Hongyu    LIANG Weimin    YU Yongqiang    WEI Haixia   
作者单位：  河南理工大学 土木工程学院,河南 焦作,454000  
刊  名：  铁道学报ISTICEIPKU  
Journal：  Journal of the China Railway Society  
年，卷(期)：  2018, 40(3)  
分类号：  U456.33  
关键词：  隧道衬砌  混凝土  爆破振动  损伤累积  爆破循环次数比  试验研究  
Keywords：  tunnel liningconcreteblasting vibrationdamage accumulationblasting cycle index ratioexper-imental study  
在线出版日期：  2018年4月13日  
基金项目：  国家自然科学基金，河南省基础与前沿技术研究  

原文网址：

1. http://d.old.wanfangdata.com.cn/Periodical/tdxb201803020

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