Mais informações

CASTRO, P. F.; CARINO, N. J. FRP: elastic modulus and bond strength. In: CONGRESSO INTERNACIONAL SOBRE O COMPORTAMENTO DE ESTRUTURAS DANIFICADAS, 2., 2000, Rio de Janeiro. Anais... Rio de Janeiro, 2000.
Clique no nome do(s) autor(es) para ver o currículo Lattes:

Dados do autor na base InfoHab:
Número de Trabalhos: 10 (Nenhum com arquivo PDF disponível)
Citações: 2
Índice h: 1  
Co-autores: Nenhum co-autor encontrado

Dados do autor na base InfoHab:
Número de Trabalhos: 4 (Com arquivo PDF disponíveis: 1)
Citações: 36
Índice h: 6  
Co-autores: Nenhum co-autor encontrado

Abstract

The substitution of steel bars with fibered reinforced plastic (FRP) bars is a development in reinforced concrete. The aim of this substitution is to make possible structures which have longer service lives, particularly under aggressive environments. Design criteria in structural codes for reinforced concrete are based on the steel reinforcement yield strength. The tensile stress-strain behavior of FRP bar is essentially liner-elastic up to the tensile strength. Hence design with FRP reinforcement cannot follow the procedure adopted for steel reinforcement. The designer needs to consider the elastic modulus of the reinforcement to calculate the stress in the bars when the concrete reaches its limiting strain. Because FRP bars are composites of different polymers and fiber, one cannot assume a fixed value of elastic modulus that is applicable to all FRP reinforcement. Thus there is a need for a standard test method to characterize the elastic modulus of FRP reinforcement. Tension tests of FRP bars have presented major difficulties to researchers due to the griping device for applying load. The normal gripping procedure for steel bars results in premature failure of FRP bars due to the combined effects of shear and crushing coupled with the tensile stress. As a result special techniques are being developed for tensile testing of FRP bars. However, the use of nondestructive testing to assess the elastic modulus could be a simpler, easier, efficient and more economical approach. In this paper the feasibility of using the ultrasonic pulse velocity and impact-resonance test for assessing FRP elastic modulus has been evaluated. Tensile force transfer results from a FRP reinforcing bar to the surrounding concrete is also an important structural design assumption . Force transfer from the bar to the surrounding concrete can be characterized by the number and spacing of the cracks that form in the strut test. A comparison of FRP bars with three different surface characteristics was carried out. The results shows that the force transfer from FRP to concrete is significantly improved when FRP bars have a sand-coated surface.
-