Mechanical Behavior and Chloride Penetration Resistance of Internal Curing Concrete

Abstract

Abstract: With the continuous advancement of China’s infrastructure construction, the requirements for concrete materials are becoming higher and higher. As a new type of internal curing material, super absorbent polymer (SAP) possesses the advantages of good water absorption and water retention, light weight and hard to dehydrate after compression, it has attracted more and more attention from scholars at home and abroad. To explore the mechanical behavior and chloride penetration resistance of SAP internal cured concrete, several groups of concrete with different SAP content and particle size were set up, and the internal micro pore structure of SAP concrete was observed and analyzed by means of nuclear magnetic resonance (NMR) and scanning electron microscope (SEM). The results show that the incorporation of SAP material can significantly reduce the early strength of concrete, and the 3 d strength can be reduced by up to 25% compared with the reference group, but the influence on the strength of the middle and later period is not very great. With the addition of SAP, the volume and number of pores in concrete are significantly reduced, and the pore structure is optimized. The addition of SAP improves the chloride penetration resistance of concrete, the 56 d impermeability is improved by 38% compared with the reference group. The chloride migration coefficient can be well predicted by BP neural network fitting.

Key words: internal curing concrete, strength of concrete, pore structure, durability, BP neural network

CLC Number:

TU528

LIU Yutao, GAO Yirong, MA Bicong. Mechanical Behavior and Chloride Penetration Resistance of Internal Curing Concrete[J]. BULLETIN OF THE CHINESE CERAMIC SOCIETY, 2023, 42(6): 2027-2036.

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