基于声发射的钢筋混凝土梁破坏损伤过程的研究

Comprehensive monitoring method of reinforcedconcrete beams based on acoustic emission

当前我国土木建设项目由高速发展阶段转变为高质量发展阶段,21世纪前后建设的工程基本已经进入保养维护阶段,为了了解建筑每个阶段的力学变化,探究钢筋混凝土梁在受到损伤时各个阶段的声发射信号的变化规律,开展了这次以截面面积与混凝土强度为变量,对4根受到损伤的混凝土梁进行检测并分析收集到的声发射参数。声发射能量的释放、累计能量等参数能够准确地反应梁的破坏阶段,试件在不同变量下,整个实验过程得到的数据趋势基本相同。随着混凝土强度的增加,破坏所需要的能量和ib值的波动频率也随之增加。截面面积的增加会使能量与ib值相对增加。而声发射ib值,相比较b值可以更加精准地反应各个阶段试件的破坏情况,可以为工程中结构健康的评估提供一定的参考,通过三种方法的对比选取适合全过程的研究方法。

At present,China's civil engineering construction projects have transitioned from a high-speed development stage to a high-quality development stage,and the construction projects around the 21st century have basically entered the maintenance and upkeep stage.In order to understand the mechanical changes in each stage of the building and explore the changes in acoustic emission signals at each stage when reinforced concrete beams are damaged,this study takes cross-sectional area and concrete strength as variables,Using acoustic emission technology to detect the damage process of four concrete specimens and analyze the collected acoustic emission parameters.The release of acoustic emission energy,cumulative energy,and other parameters can accurately reflect the failure stage of the beam.Under different variables of the specimen,the data trend obtained during the entire experimental process is basically the same.As the strength of concrete increases,the energy required for failure and the fluctuation frequency of ib value also increase.An increase in cross-sectional area will result in a relative increase in energy and ib value.The ib value of acoustic emission,compared to the b value,can more accurately reflect the damage situation of specimens at various stages,and can provide a certain reference for the evaluation of structural health in engineering.Through the comparison of the three methods,a comprehensive method suitable for the whole process was selected.