利用LDV测量空鼓声振特性的非接触式检测方法

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中图分类号：TB9;TH89 文献标志码：A文章编号：1674-5124（2025）11-0001-08

Abstract： A detection method based on Laser Doppler Vibrometry （LDV） is proposed to analyze the acousticvibrationcharacteristicsof debondingdefects inbuilding exterior wallfinishes.First，thedebonding structure is modeled as a clamped thin circular plate，and its natural frequencies and mode shapes are calculated. Debonding samples of different diameters are fabricated accordingly. Next，an experimental setup consisting of an acoustic excitation system and an LDV measurement system is constructed to investigate the vibration characteristics of the debonded regions.Finally，swept-frequency acoustic excitation is applied to the samples， and the surface vibration signals of the debonded areas are acquired using LDV for amplitude-frequency analysis.Experimentalresults show that，under the given conditions，the first natural frequencies corresponding to debonded regions with diameters of 100mm 110mm. and 120mm are 3027Hz，2641Hz and 2282Hz respectively. The discrepancies between the experimental results and theoretical calculations of the first natural frequencies are all within 5% . The single-point amplitude-frequency response curve clearly identifies the resonance peaks of the debonded areas，while the multi-point vibration intensity maps visually reveal the geometric shapes of the debonding defects.

Keywords： hollow drum; acoustic-vibration characteristic; laser Doppler vibration measurement technology; natural frequency

0 引言

在高层建筑中，外墙面砖因其美观、经济等优势成为一种常见的装修形式；然而，在实际施工时，由于施工技术问题、面砖自身材料缺陷、粘结剂质量不佳、基层不牢靠、环境变化导致材料热胀冷缩不同步等各种原因，会出现空鼓现象。（剩余9286字）