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The steam curing technology is worldwide applied in the production of concrete prefabricated components, including the production of track slab and girder used for the high‐speed railway in China. However, the steam curing process at elevated temperature will often generate the heat damage on concrete and thus degrade the long‐term performance of the steam‐cured concrete prefabricated components. It is very important to deeply understand the mechanism of heat damage and thus to find effective method reducing or avoiding the damage of steam curing on concrete. The main purpose of this paper is to systematically classify the types of thermal damages on concrete during the steam curing and its mechanism. The influences of main factors on three thermal damages such as the unrecoverable expansion deformation, the surface layer defect, and the embrittlement of the steam‐cured concrete are discussed in detail. The controlling methods of thermal damages including optimization of the steam curing regime and mixing proportions, the addition of supplementary additives, the self‐healing technology, and other curing technology are compared and summarized based on the literatures. Finally, suggestions for future research are proposed in order to effectively reduce or even avoid the thermal damage of the steam‐cured concrete. And also, some new technology for developing the green and high performance early strength concrete with low CO2 emission are presented. [ABSTRACT FROM AUTHOR]

Precast concrete structure has been increasingly used all over the world. Its seismic performance has always been the key factor of its application in earthquake‐affected zones, especially in China. A new precast concrete shear wall structure using grouted lap splice connection and cast‐in‐place concrete was proposed in this paper. Low‐cyclic reversed load testing was conducted on a one‐half scale spatial specimen of the bottom four stories of the new precast concrete shear wall structure. The test results were compared with the push‐over analysis results to evaluate the seismic performance of the specimen. The specimen showed good integrity and satisfies the current demands for Chinese seismic fortification. Moreover, due to the effect of infill walls strengthening the shear walls, and the effect of local cast‐in‐situ concrete regions constraining the precast components and connecting transverse walls to longitudinal walls, the specimen performed as tube structure and possessed excessive strength and stiffness. [ABSTRACT FROM AUTHOR]