混凝土早期导热和导温系数试验研究

On the basis of the hot wire parallel technique, a new apparatus which is used to measure the thermal conductivity and thermal diffusivity of concrete at the early-age is designed. The apparatus is made up with seven parts which are the casting mould, heating probe, thermistor sensor, universal meter, power supply, temperature display instrument and the data acquisition software. Meanwhile, an experimental study on thermal conductivity and thermal diffusivity of hydrating concrete in their fresh state and during the course of 7d of hydration at 20℃.Variables investigated include five water-to-cement mass ratio. The experimental results indicate that no serious differences among the five group specimens on the development law of the thermal conductivity and thermal diffusivity during the hydrating process. And the regularity among the five group specimen shows a good consistency. Moreover, the general character on the development law has been summarized seriously. Further, the results show that the thermal conductivity and thermal diffusivity of concrete decreases with the increase of water-cement ratio.