Mechanical Properties of Polyurethane Coated Reinforced Concrete Beams

Abstract

Abstract: Experimental investigation was conducted using concrete specimens to assess the effectiveness of polyurethane (PU) coating in enhancing the mechanical response of concrete specimens under static and impact loads. Three point bending tests were carried out at strain rates of 0.000 3 s^-1 and 0.065 s^-1 to simulate static and impact loads. The results show that the application of PU coating (on the front or reverse of concrete specimens) has a positive effect on improving the ductility of concrete structure. The maximum strain and cumulative strain energy increase linearly with the increase of PU coating thickness. The method of reverse coating is more efficient in strengthening concrete structure under static load, and the method of front coating enhances the impact resistance of concrete structure. The strengthening ability is effectively improved by the increase of coating thickness. PU coating does not debond during the ultimate failure of test specimens, which implies that the material has good adhesion characteristics and effectively reduces the crushing effect of specimens.

Key words: polyurethane, concrete beam, coating thickness, dynamic loading, three point bending, fracturing mode

CLC Number:

TU528

LEI Bo, HUANG Xianbin. Mechanical Properties of Polyurethane Coated Reinforced Concrete Beams[J]. BULLETIN OF THE CHINESE CERAMIC SOCIETY, 2022, 41(1): 134-140.

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