Summary: | 碩士 === 朝陽科技大學 === 營建工程系碩士班 === 91 === This research uses the data process technology of new transfer function developed from impact-echo method of non-destructive test to evaluate the bond quality of an interface between the existing concrete and the non-shrinkage mortar. The repair of concrete structure contains of removing poor quality or damaged concrete, then covering new repair materials. The proper interface treatment of old concrete and the bond strength of the bonding materials are important factors for successful repairing.
This research is separated into two parts as laboratory and field studies. About laboratory study, a plate specimen was cast. On the interface between the existing concrete and the non-shrinkage mortar, different surface treatments were done at different part. The impact-echo and pull-off tests were performed afterwards. About field study, a practical repairing case for box girder was used to proceed impact-echo test and to do advanced analysis of transfer function. This research shows that the peak frequency which corresponds to the whole thickness of concrete plate is lower down when you check the bad repairing interface. As a result, the error of calculated plate thickness is more than 16%. The amplitude of peak corresponding to plate thickness is also lower, and the peak amplitude corresponding to the depth of interface is larger. If these three indexes mentioned above are normal, there is no obvious flaw for repairing interface. However, on the other hand, the strength of bond interface is directly related to the strength of the bonding material.
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