Investigation of fiber reinforced ferrocement composites in retrofitting reinforced concrete beams

Reinforced concrete bridge decks tend to deteriorate over time due to the increase in live load and corrosion of reinforcement and many other reasons. Economic factors do not allow for a complete replacement of such structures which validates the importance of concrete rehabilitation technologies. With the launch of high performance materials, the use of cementitious composites for infrastructure application for rehabilitation has become more common. Ferrocement application for bridge decks repairs is inexpensive and can extend the life of the bridge by 5 to 10 years. This study presents the results of an experimental research performed to investigate the behavior of damaged reinforced concrete beams repaired with fiber reinforced ferrocement laminate. The ferrocement layer acts as a replacement to a damaged or peeled off clear cover. A total of 30 beams were tested under two point loading system up to failure. The research work discusses the effect of; the number and type of reinforcement in the laminate, and the incorporation of macro polypropylene fibers at different volume in the mortar used for the repair layer. The beams differed by their reinforcement ratios in the ferrocement laminate, thickness of the lamniate, size and number of shear studs which act as a bond between the two layers. All beams are designed to fail in flexure. Results showed that the beams tested had noticeable improvement in terms of ductility, cracking strength (163%) and ultimate capacity (109%). The results also showed the material properties of multiple mortar mixes that were considered to be used for the fabrication of the repair layers. These mixes differed by their cementitious components, fibers content, and other parameters that will be discussed later on are in the study.M.S.Includes bibliographical referencesby Elie I. Hadda