Modeling and testing fiber-reinforced polymers in civil structures

This research investigated the numerical and experimental characterization of Fiber Reinforced Polymers (FRPs) in civil applications. This thesis addressed three topics.; The first part focused on a relatively recent technique used to strengthen Reinforced Concrete (RC) beams in flexure. Although researchers have extensively studied the failure mechanisms of post-strengthened systems, brittle failure modes, such as shear failure at the plate end, midspan debonding and end peeling, need to be further investigated. The influence of various parameters on the failure mechanisms were investigated in this thesis. The investigation proved that the use of FRPs in RC beam strengthening increase significantly the load carrying capacity of the beam and found that the parameters studied play a significant role in the failure mode and ductility of the RC beam.; The second theme aimed to develop a simplified stochastic model to predict the failure of unidirectional single ply composites. Due to the heterogeneous properties of the constituents and the manufacturing process these materials show a high degree of variability, therefore a deterministic approach, such as the well-known Rule Of Mixture, cannot lead to satisfactory results. To have confidence in this approach requires information on the statistics nature and reliable models. The simulations obtained with the model proposed agree very well with the experiments analyzed, and the parametric analysis had addressed several important issues concerning the failure process of single ply unidirectional composites.; The third part of the thesis evaluated the Glass FRP deck panel for the O'Fallon Park bridge. The bridge deck is constructed using a sandwich panel configuration, which is a structural member composed of two stiff faces separated by a light-weight core. The scope of this study was to evaluate the design and investigate short and long term performance of the deck. An experimental study was carried out. The load carrying capacity, the governing failure mode and the fatigue resistance of the honeycomb panel were investigated. This study proved the safety of the deck and calculated the load distribution of this type of deck.