红外热像法识别粘钢法加固混凝土结构空鼓缺陷研究

Study on infrared thermography technology used for detecting the bond defects of steel-bonded reinforcement concrete structure

基于ANSYS有限元方法,模拟分析胶粘层不同缺陷尺寸和类型,分类研究钢板内侧粘结层缺陷尺寸与钢板表面温度分布的关系.结果表明:在同一热激励下,当粘结空鼓缺陷远离钢板,且空鼓与钢板之间存在结构胶夹层时,长时间的激励才能在钢板外表面形成粘结空鼓中心与边缘的较大温差.由于热量向空鼓方向传递的同时也沿钢板平面向周围传递,造成钢板外表面温度变化不明显,因此检测识别较为困难.

The different defect sizes and types of the bond layer of the RC members bonded with steel plate are simulated and analyzed by ANSYS finite element method, and the relationship is classified between the layer defect sizes and the temperature distribution on the out surface of steel. According to the results, under the same thermal excitation, when bonding defects are far away from the steel plate and there is a thin bonding layer between the defects and the steel plate, longer thermal excitation time will be required to get the maximum temperature differences on the steel’s outer surface between the center and the edge of the bonding defects. For the reasons that heat transfers not only to defects but also to the surroundings along the steel plate plane, the temperature variation on the steel outer surface are less obvious. All these result in the difficulties of defects detecting.