This paper focuses on the multi-physical fields' evolution in early age concrete, which has great importance to the work performance and durability of concrete material. This paper presented some simple and comprehensible formulas to connect different multi-physical field of early age concrete. Then a simplified model is proposed to analyze the early age concrete after which the numerical analysis methods are built. We compared the simulated results with the passively confined concrete experiments data and find they agree well, which proved this method feasible and effective.