Carbon Fiber Smart Concrete - The Heat - Stress Effect Study

Carbon fiber conductive concrete (CFCC) is kind of multifunctional cement based composite material by uniformly admixing short carbon fiber to concrete. Compare to the normal concrete, mechanical and conductive characters are greatly improved. Exerts electric to CFCC will have the Joule heating effect in it because of the conductivity character; meanwhile the thermal will cause deformation. So the CFCC can be used to melt the snow and ice on the road and deformation self-adjustment in structure. The conclusions and innovation are as following:1. The principle of the conductivity, producing technics and the factors which influence the conductive properties of CFCC were discussed in the paper. The influences of carbon fiber ratio, water/cement ratio, sand/cement ratio and curving age on CFRC were studied based on the best producing technics.2. The Joule heating effect was discussed in this chapter. Firstly consider the effect of the polarization and contact-resistance, and then to study the stability of the resistance and thermo-sensitive effect of CFCC, at last, the factors which influence the heating effect of CFCC were discussed, such as wet and dry environment, low temperature, DC and alternating current.3. Determine the thermal-expansion coefficient of CFCC by experiment.4. Based on the Joule heating effect, there will have deflections of the beam which has two layers, one layer is normal concrete and the other layer has carbon fiber in it by heating up the CFCC. Three methods were discussed to study the electricity-thermo-deformation effect: the theory, the experiment and the infinite element method. The influences of the power, the thickness of carbon fiber layer on the electricity-thermo-deformation effect of CFCC were studied at last.