基于脉冲响应法识别混凝土面板与土体界面脱空试验

Experimental Study of Detection of Void Between Concrete Slab and Soil Based on Impulse Response Method

摘要:

研究了脉冲响应法在识别混凝土面板脱空中的应用.介绍了混凝土面板脱空危害，分析了现有检测方法的局限性；阐述利用脉冲响应法进行混凝土面板脱空无损检测的基本原理和优点；利用该法进行混凝土面板脱空检测的模型试验研究.试验中采用在模型土体上现浇的混凝土板，并在板上布置传感器，通过力锤敲击混凝土板产生应力波，利用传感器采集混凝土板的动态响应且进行相应的数据处理和分析，进而得到混凝土板下方的脱空情况.检测结果与板下实际脱空情况的对比表明，运用脉冲响应法检测板下脱空在实践中是可行的，且效率较高,操作简便.为今后检测混凝土面板脱空和评价脱空修复效果提供了一种新途径.

Abstract:

This paper focused on the application of the impulse response method to detect void under concrete slab. First, the perniciousness of void under concrete slab was introduced, and the limitations of current detection methods were analyzed. Then, the basic principle and the advantages of the impulse response method were described. After that, model tests on detection of void under concrete slab by using the impulse response method were performed to demonstrate the feasibility of the method. During the experiment, soil was first filled into a test chamber to make a model ground, and a concrete slab was casted on the ground surface. The concrete slab was knocked by a hammer at a certain point to create stress wave. The dynamic responses of the concrete slab were measured by the sensors located at different places on the concrete slab. The obtained data were processed and analyzed using the impulse response method, and the positions and ranges of the voids under the concrete slab were further identified. The identification results were compared with the actual void situations under the concrete slab. The impulse response method was proved to be feasible and efficient in detecting the void phenomenon under concrete slab, thus providing a new way to detect void and evaluate the effect of repair.