Influence of the bonding of rebar dowel with adhesive on wood-concrete composite specimens

Abstract

Ensuring the quality of the connector used in wood-concrete composite systems is a critical factor affecting the performance of the system. The main objective of this research was to study the strength and stiffness of wood-concrete composite specimens with two types of rebar dowel connectors: fixed to the wood (solid timber) using epoxy adhesive and by pre-drilling on smaller diameter holes in the wood (without the use of adhesive). In the composition of the test specimens, rebar dowels of 12·7 mm dia. were used. The strength and stiffness of the connectors were determined by double shear tests, performed on composite specimens. Statistical analysis was used to compare the results obtained and regression models were proposed for estimating the stiffness parameters of the connections. The connectors glued with epoxy adhesive provided better strength and stiffness for the composite specimens when compared to the connectors fixed to the wood by pre-drilling. The differences between the strength and stiffness of the connection systems analysed were statistically significant. The regression models proposed presented a good approximation for the estimation of the Kser and Ku slip moduli of the composite specimens analysed.