Numerical Simulation of Pile Foundation Conduction at Different Molding Temperature in Permafrost Regions

In this paper, the integration of foundation pile conduction, frozen soil, air temperature, concrete hydrate heat, concrete molding temperature is considered to establish a numerical simulation. By numerical analysis, the process of pile foundation in cold seasons of Qinghai_Tibet railway, increasing of concrete of molding temperature and its impact to construction are studied. Through the study, it is showed that the effect of concrete hydrate to ground temperature decreases with the increasing of the re_freezing time. After the two months' refreeze time, single pile body temperature reached the temperature nature holes' 57.3% and 53% at the entering models temperature of 5 ℃and 12 ℃respectively. So it is not practical to the construction if the effect of the concrete hydrate is eliminated completely. In fact, it is available if the carrying capacity of piles foundation is strong enough.