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Heat Curing may lead to high early strength for concrete but weakened mechanical and durability performance at later stage because of its poor microstructure formed by the rapid precipitation of hydration products at early stage, especially the subsequent complex curing condition.The effect of heating temperature and subsequent curing condition on the microstructure, morphology ,porosity ,distribution of hydration products and the silicate anion structure of C-S-H were investigated by kinds of test technology ,such as ESEM, XRD, TG, BSE-IA,NMR etc.The maximum temperature was 55 & 65 ℃ with the heating & cooling rate 15℃/h, the subsequent curing regimes were designed to be standard curing, indoor curing and outdoor curing, which was aimed to study the effect of subsequent complex curing condition on microstructure and properties after heat curing.The results show that the samples with heat curing has a higher hydration degree at early stage but a lower later hydration degree, the distribution of hydration products is much more heterogeneous with a coarse porosity, and the morphology of calcium hydroxide, AFt and AFm is different from curing at standard condition, and the increased temperature made the difference greater.The subsequent curing condition also shows a significant influence on the microstructure of cement paste and the silicate anion structure of C-S-H.