双横波声速法检测单向受压混凝土构件永存应力*

该文力求寻找一种高效准确检测混凝土构件永存应力的方法。基于声弹性理论提出了一种双横波声速法检测单向受压混凝土构件永存应力的方法,该方法通过测试受力构件第一波速和第二波速,以第一波速和第二波速的平方差为基础构建综合声学参数来检测单向受压混凝土构件永存应力。所述第一波速为声波传播方向与应力方向垂直、质点振动方向与应力方向平行的横波波速,第二波速为声波传播方向及质点振动方向均与应力方向垂直的横波波速。实验结果显示,该声学参数用于检测混凝土单向受压构件永存应力的效果与使用单一声速参数相比,对应力的敏感性有所提高,受混凝土黏滞性及材质离散性的影响更小,并且测试结果基本不受温度和湿度变化影响。

Study on the method of double shear wave velocity to detect the permanent stress of concrete members under uniaxial compression

This paper tries to find an efficient and accurate method to detect the permanent stress of concrete members. Based on the acoustoelastic theory, a method of detecting the permanent stress of concrete members under uniaxial compression by using the double shear wave sound velocity method is proposed. The method detects the permanent stress of concrete members under uniaxial compression by testing the first and second wave velocities, and constructs a comprehensive acoustic parameter based on the square difference of the first and second wave velocities. The first wave velocity is the shear wave velocity in which the sound wave propagation direction is perpendicular to the stress direction and the particle vibration direction is parallel to the stress direction, and the second wave velocity is the shear wave velocity in which both the sound wave propagation direction and the particle vibration direction are perpendicular to the stress direction. The experimental results show that the effect of the acoustic parameter used to detect the permanent stress of concrete members under uniaxial compression is better than that of using a single sound velocity parameter, which is less affected by the concrete viscosity and material dispersion, and the test results are basically not affected by the changes of temperature and humidity.