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A room using carbon black mortar slabs (CBMS) as the electrical floor heating element has been built in our lab. Studies showed that an electrical power of about 123.8 W/m2 resulted in the indoor temperature rise of 10 °C within 330 min. Temperature distribution along the height of the room was uniform. Temperature rise was slightly higher if floor tiles rather than the wood flooring was used. In the process of heating, self-heating of CBMS has consumed more than 30% of the generated heat by Joule effect, which was advantageous for the stability of the thermal state. The indoor air absorbed over 50% of the generated heat. Results derived from repeated tests show that the electrical power of the CBMS system was stable during several cycles of heating. Further, the procedure and power consumption for the system to maintain a certain indoor temperature were studied. Continuous tests for 72 h has shown that the higher the indoor controlled temperature was, the longer the working time and the shorter the rest time in every cycle of heating were required. Accordingly, the power consumption to maintain the heat state increased with the controlled temperature increasing.

Electrical emission (EM) signals, which are generated from the concrete specimens under three-point bending tests, were conducted. It is shown that electrical emission phenomena are related to cracking of the specimens, cohesive failure, contact-separation etc. The simultaneous appearance of electric emission signals and visible cracks during the flexure loading of beams was also observed.

Infrared thermal imaging technology is one new method of the modern non-destructive testing. Expanding the qualitative analysis to quantitative characterization is hot and difficult of the infrared thermal imaging technology, that is to say, expanding assessing whether damage and judging injury location to structural integrity evaluation. The key lies in the extraction and description of the infrared thermal imaging characteristics parameters. This paper did fractal study on the experimental samples of infrared thermal imaging, including infrared thermal imaging graphics processing, fractal dimension calculation, realization of calculation program and gray, network and scale and so on, which is the foundation for further study on concrete structure damage and fracture or fracture criterion and the experimental calibration.

Carbon fiber reinforced concrete (CFRC) is an intrinsically smart material that can sense not only compressive or tensile stress, but also temperature. The thermal self-monitoring ability is associated with the Seebeck effect. An experimental study was made to examine the relationship between the temperature differential (ΔT) and thermoelectric force (TEF)—its sensitivity and repeatability, its response time and the influence of ambient temperature (Ta) on TEF. The results show that TEF is proportional to ΔT over a wide range of temperature, and the thermal self-monitoring CFRC possesses high sensitivity and good repeatability. The Ta has no influence on TEF. Although the response time of CFRC is not fast enough because of its low heat conductivity, it can be used as a thermal sensor embedded in massive concrete structures, such as water dams and bridges, where the temperature changes slowly.