Theoretical analysis on long-term deflection of GFRP-concrete hybrid structures with partial interaction

The creep and shrinkage of concrete and the creep of glass-fiber reinforced polymer (GFRP) may lead to the increase of long-term deflection of GFRP-concrete hybrid structures under service loading, due to the change of internal forces and stresses. This paper presents a calculation model to consider the influence of the aforementioned changes in analyzing the long-term deflection of GFRP-concrete hybrid structures with partial interaction under service loading, based on the age-adjusted effective modulus method (AEMM). The calculated results from the proposed calculation model agree well with the available experimental results. A further discussion is also made about the effects of the concrete creep and shrinkage and the GFRP creep, as well as the shear stiffness of shear connectors on long-term behavior of GFRP-concrete hybrid structures. Especially, the significant influence of concrete shrinkage on long-term interface slip, interface shear and long-term deflection is found. What's more, the long-term deflection may increase with the augment of horizontal shear stiffness of shear connectors.