Bond strength between concrete layers of three-layer concrete structures

Abstract

Development of the methods for the calculating reinforced concrete structures covers a wide range of issues, including the expansion of the application of new innovative materials such as concrete and reinforcement. In practice, modern construction of multilayer structures is made of concrete with different strengths and it is compulsory to conduct numerical and experimental studies of the bond strength between concrete layers with different strengths. In this study, the influence of some physical-mechanical factors and temporal manufacturing parameters on the monolithic bond of concrete layers of three-layer structures made of concrete with different densities according depending on the sample is considered. An experiment was conducted to evaluate the development of the shear bond strength between two concrete layers of three-layers sandwich concrete. Three-layer samples consist of normal concrete (NC) in the external layers and lightweight concrete (LWC) in the inner layer. The results of the study show that these factors directly affect the monolithic bond of concrete layers in three-layer structures, which are made by concrete of different strengths. The obtained scientific results allow the determination of reasonable parameters to ensure the monolithic bond of concrete layers with different strengths of the 3-layers structure in design and production.