振动荷载作用下新浇混凝土损伤累积规律试验研究  

Experimental research on damage accumulation law of new concrete with blasting vibration

作　　者：杨小林 刘宝 吴礼报 YANG Xiaolin;LIU Bao;WU Libao(College of Civil Engineering,Henan Polytechnic University,Jiaozuo 454000,China)

机构地区：[1]河南理工大学土木工程学院,河南焦作454000

出　　处：《混凝土》2020年第9期27-30,36,共5页Concrete

基　　金：国家自然科学基金资助(11542019,51874123);河南省基础与前沿技术研究(162300410032)。

摘　　要：为探究新浇混凝土在爆破振动作用下的损伤累积规律与爆破振动安全控制标准,在理论分析混凝土振动损伤累积机制的基础上,设计了新浇混凝土爆破振动模拟试验,利用多次振动荷载作用下混凝土超声波波速值来计算损伤值,进而研究振动荷载作用下新浇混凝土损伤累积机制与规律。结果表明:(1)当振速V≤1.0 cm/s时,不产生损伤劣化效应;当振速1.5≤V≤3.0 cm/s时,当龄期小于60 h,损伤效应不显现,当龄期大于60 h,损伤效应显现;当振速V>3.0 cm/s时,尤其振速V>5.0 cm/s时,损伤效应宏观显现。(2)考虑损伤累积劣化效应的新浇混凝土爆破振动安全速度应小于2.0 cm/s,对于龄期60 h内新浇混凝土安全振动速度应控制在3.0 cm/s以内。In order to explore the damage accumulation law and blasting vibration safety control standard of new concrete under blasting vibration,based on the theoretical analysis of concrete vibration damage accumulation mechanism,The simulation experiment of blasting vibration of new concrete was designed.The damage value of the concrete ultrasonic wave velocity of multiple vibration loads was calculated.And then the damage accumulation mechanism and law of the new concrete under vibration load were studied.The results show that:(1)When the vibration velocity is no greater than 1.0 cm/s,no damage deterioration effect occurs.when the vibration velocity is from 1.5 cm/s to 3.0 cm/s,The damage effect does not appear when the days less than 60 h.the damage effect appears when the days is bigger than 60 h.when the vibration velocity is greater than 3.0 cm/s,especially when the vibration velocity is greater than 5.0 cm/s,the damage effect appears macroscopically.(2)Considering the cumulative damage effect of damage,the safe speed of new concrete blasting vibration should be less than 2.0 cm/s,and the safe vibration speed of new concrete within 60 h should be controlled within 3.0 cm/s.

关 键 词：新浇混凝土 振动模拟 振速 损伤累积 

分 类 号：TU528.01[建筑科学—建筑技术科学]