José Sena-Cruz

Analytical Bond Model for GFRP Bars to Steel Fiber Reinforced Self-Compacting Concrete

AbstractThe objective of this study is to present a computational algorithm to analytically evaluate the bond behavior between glass fiber reinforced polymer (GFRP) bar and steel fiber reinforced self-compacting concrete (SFRSCC). The type of information to be derived is appropriate to study the flexural behavior of SFRSCC beams reinforced with GFRP bars in terms of serviceability limit states requirements; in fact, the bond between bars and surrounding concrete influences significantly the crack width and crack spacing. The proposed bond model was established by calibrating the parameters of a multilinear bond-slip constitutive law using the experimental results of pullout bending tests carried out by the authors, taking into account the experimental pullout force versus slip at loaded and free ends. According to the comparison between theoretical and experimental pullout force-slip, an acceptable accuracy of the model was observed. Additionally, by considering the proposed bond-slip relationship, a para...

Bond between concrete and multi-directional CFRP laminates

Recently, laminates of multi-directional carbon fiber reinforced polymers (MDL-CFRP) have been developed for Civil Engineering applications. A MDL-CFRP laminate has fibers in distinct directions that can be arranged in order to optimize stiffness and/or strength requisites. These laminates can be conceived in order to be fixed to structural elements with anchors, resulting high effective strengthening systems. To evaluate the strengthening potentialities of this type of laminates, pullout tests were carried out. The influence of the number of anchors, their geometric location and the applied pre-stress are analyzed. The present work describes the carried-out tests and presents and analyzes the most significant obtained results.

Axial performance of jointed sandwich wall panels

AbstractThroughout this paper, a new system for connecting composite sandwich wall panels is proposed. The relevant structural components are investigated with the aim of utilizing these panels as ...

Advancements in retrofitting reinforced concrete structures by the use of CFRP materials

Reinforced concrete is nowadays one of the major structural materials used in infrastructures’ construction. As the years passed since the beginning of its use, technology has changed and today it is known that a large number of constructions do not verify some of the most recent safety requirements in addition to the durability problems that several structures face. This calls for the need for corrections and/or strengthening activities. Fibre Reinforced Polymer materials (FRP) have been used in Civil Engineering applications due to: lightweight, good mechanical properties (stiffness and strength), corrosion-resistant, good fatigue behaviour, easy application and virtually endless variety of shapes available. Recent advancements in retrofitting reinforced concrete structures by the use of CFRP materials promoted by the authors of the present chapter are herein summarized. Firstly a brief overview on the most common properties of old reinforced concrete constructions those who might need for interventions, is presented. Then, the most common repairing and/or strengthening techniques are addressed. Finally, a deeper look is taken on the new repairing and/or strengthening techniques using FRP reinforcements.