锚杆低应变动测的数值研究

岩石声波测试技术应用于锚固工程的无损检测中，其基本原理是采用动力瞬态激振，使锚杆引起弹性振动，通过测定锚杆的振动响应来估计和推断锚杆中的缺陷。该方法在力学上表现为给定扰动源信息及边界、初始条件，建立描述介质运动的支配方程，并由此求解其动力响应，通常归结为双曲型或双曲-扩散型方程的初值或初值-边值问题．波动方程的有限元数值解表明，在锚杆灌浆体内部缺陷的探测中，可用声速、幅值、波形等声参数作为判断的依据，若再加上在缺陷处的频谱畸变参数，则可使判断更为可靠。

NUMERICAL STUDY OF LOW STRAIN DYNAMIC TEST FOR BOLT

Sonoprobe method has been applied in non-destructive inspect of bolt-supported project,with the fundament that dynamic transient excitation causes the elastic vibration of bolt,and flaws can be estimated or dedermined by analysing transient response of bolt. In the mechanics field this method means that if the information of disturbance resource,boundary conditions and initial conditions has been given,the dominant equation describing medium motion could be established and then the dynamic response solved. Usually it comes down to the question of initial value or initial-boundary value of hyperbolic equation or hyperbolic- diffusibility equation. FE solution is made on the hyperbolic equation,based on acoustic parameters,such as velocity of sound,vibration range,wave shape,etc,when inspecting interior flaws of grout of bolt. The obtained estimation is more credible with the spectrum aberration taken into account.