Time-dependent and sensitivity analysis of interfacial stress in RC simply-supported beam strengthened by bonded laminates

To study the influences of the concrete shrinkage and creep effect and the related different parameters on the interfacial stress in the concrete beam strengthened by the bonded laminates, a typical reinforced concrete (RC) simply-supported beam strengthened by the bonded laminates was taken as the research object, the closed-form solution of the interfacial stress considering the concrete time-dependent characteristic was derived, the tendencies of the influences of changing of the different parameters on the interfacial stress were analyzed and on the fundamental principle of the sensitivity analysis, the degrees of the sensitivity of the interfacial stress to the different parameters were investigated from the point of the quantitative analysis. The results show that the concrete time-dependent effect causes the interfacial shear stress and peeling stress to increase with the increase of time. The thicker the adhesive layer is, the less the elastic modulus of the adhesive layer will be. The thinner a bonded laminate is, the less the elastic modulus of the laminate will be. The closer the laminate to the bearing is, the less the interfacial stress will be. The parameter that influences the interfacial shear stress in the edge of the bonded laminate most sensitively is the distance from the edge of the laminate to the bearing while the parameter that influences the interfacial peeling stress in the edge of the laminate most sensitively is the thickness of the laminate. © 2016, Journal Press, China Railway Bridge Science. All right reserved.