采样定理在冲击回波法检测混凝土内部损伤中的应用研究  

Study on the Application of Sampling Theorem in the Detection of Concrete Internal Damage by Impact-Echo Method

作　　者：杨海林 YANG Hailin(Tangshan Polytechnic College,Tangshan 063299,China)

机构地区：[1]唐山工业职业技术学院,河北唐山063299

出　　处：《工业技术与职业教育》2023年第3期17-21,共5页Industrial Technology and Vocational Education

基　　金：2021—2022年度唐山工业职业技术学院院级课题“冲击回波法检测火灾后混凝土内部损伤的应用研究”(课题编号:YJKT202110),主持人杨海林。

摘　　要：针对冲击回波法检测混凝土内部损伤产生的连续波形信号,通过理论分析与实例验证,研究了采样定理在信号处理过程中的应用,结果表明:采样问题是信号处理领域的核心问题,连续信号和离散信号在一定条件下可以互相转换;当采样周期小于正弦信号周期的一半时,离散信号可以恢复成原始连续信号;当采样周期等于波形信号的半周期时,采样定理能在特定条件下应用;采样周期越小,得到的采样信号越好,实际工程中,在综合考虑计算系统承受能力的情况下可适当提高采样频率。Aiming at the continuous waveform signal generated by the impact-echo method to detect the internal damage of concrete,the application of the sampling theorem in the signal processing was studied through theoretical analysis and practical verification.The results show that:the sampling problem is the core problem in the field of signal processing,and continuous signal and discrete signal can be mutually converted under certain conditions;when the sampling period is less than half of the sinusoidal signal period,the discrete signal can be restored to the original continuous signal;when the sampling period is equal to the half period of the waveform signal,the sampling theorem can only be applied under certain conditions;the smaller the sampling period is,the better the sampling signal will be obtained.In practical engineering,the sampling frequency can be appropriately increased under the condition of comprehensively considering the bearing capacity of the calculation system.

关 键 词：连续信号 离散信号 采样周期 采样定理 冲击回波 

分 类 号：TU375[建筑科学—结构工程]