Research of infrared radiation characteristics of concrete deformation and failure

Uniaxial compression test was conducted on concrete samples, and change characteristics of infrared radiation and acoustic emission of the samples in loading process were tested and studied by use of infrared imager and acoustic emission instrument. The research results show that infrared radiation temperature curve presents decreasing firstly and then increasing in the loaded concrete samples failure process, and temperature increasing amplitude of average infrared radiation temperature and the maximum infrared radiation temperature are respectively 0.15 ℃ and 1.05 ℃ when the samples failure. Before the samples failure, the average infrared radiation temperature has obvious precursor information that the temperature quickly drops at 66.7% load ratio and rises at 82.6% load ratio. During stage of the concrete samples fracture and its development, low and high temperature bands appear on infrared images, the high temperature bands appear in friction area of two fracture surfaces, as well as the low temperature bands are corresponding with sample cracks which are in tension fracture zone. Infrared radiation evolution characteristics of concrete deformation and failure provide a new method for concrete engineering destruction monitoring.