Determination of the strength of the support sections of concrete beams with BFRP under the action of shear forces

Abstract

In a few foreign codes (ACI, Eurocode 2, JSCE, CSA, CNR), the principles for calculating flexible concrete elements with (BFRP) are preserved the same as for calculating concrete structures with steel reinforcement. Experimental studies have not confirmed these principles, which indicates the relevance of research. Two calculation models are proposed for determining the strength near the support sections of concrete beams with BFRP. The first model considers the calculation of beams with average (a/d=2) and large (a/d=3) shear spans along the main inclined crack, taking into account the experimentally established length of its projection lcrf1, the coefficients ϕख़2, ϕख़3 and ϕख़4 the magnitude of tensile stresses in the transverse fittings. The second computational model provides for the calculation of these beams with small shear spans (a/d<1) along a compressed inclined strip using the experimentally established coefficient kf,. The use of the presented design models provides good convergence (coefficient of variation ν=8%) of the calculated and experimental values of strength near the support sections of concrete beams with BFRP.