Advanced Composites for Design and Rehabilitation of Hydraulic Structures Piyush Ram Soti West Virginia University Concrete and steel have been predominantly used in civil and hydraulic infrastructure construction. With several years of service under adverse climatic conditions, those structures have exhibited moderate to severe deterioration and composite materials are emerging as one of the most feasible and economical materials for their rehabilitation. This report describes and highlights the research work conducted on: i) rehabilitation of underwater concrete structures with FRP, and ii) evaluation of abrasion resistant coatings for hydraulic steel gates. Curing of certain class of resins under water has unfolded the possibility of utilizing fiber reinforced polymers (FRPs) to repair submerged piles and pier structures. In this study, GFRP pre-preg with water curable urethane resin was used to wrap concrete cylinders. Laboratory testing shows the increase in strength, stiffness, and ductility of concrete cylinders with underwater FRP wrapping. Lab evaluation also indicates that underwater FRP system is effective in dry surface wrapping (ambient field conditions) as well. Threefold increase in load capacity (1921 psi vs. 6865 psi) and 3.22 times increment in energy absorption was observed with 5 layers of wrapping. Concrete cylinders with steel sections and wrapped with 2 layers of Aquawrap also showed significant increase in load capacity with more than 92% degree of compositeness. By applying basic confinement effect equations, theoretical strengths were in good correlation with experimental values. Following lab work, the rehabilitation work was conducted on submerged concrete discharge ports of Chickamauga lock and dam, and steel piles of East Lynn Lake Bridge. This research also focuses on the study of abrasion characteristics and comparative abrasion tests on different abrasion resistant coating systems. Conditions of severe abrasion exist at some high-lift dams that cause standard protective coatings on the downstream side of tainter gates to be abraded away in just few years of service. Downstream side of protective coating system is damaged typically by debris that swirls and bangs against the gate causing severe cutting and abrasion to the coatings. This study was aimed at identifying composite based coating that can withstand hydraulic forces from high velocity water and also minimize the effects of severe cutting, impact, and abrasive forces generated from barge and sand particles on tainter gates at Heflin Lock & Dam near Gainesville, Alabama. In this research, six different types of abrasion resistant coating materials/systems were applied on sand blasted metallic plates in order to perform comparative abrasion tests using TABER reciprocating abrader. Among six different coating systems, ceramic composite based coatings provided better performance (up to twice or better) over the conventional coatings.
Hydraulic gates need to be lightweight , corrosion-resistant, maintenance-free, and durable with high endurance under fatigue loads. All of these requirements could be challenges to be met using conventional materials like steel and concrete. However, with the emergence of advanced Fiber Reinforced Polymer (FRP) composites for waterway structures, it has now been possible to achieve all of these physical and performance requirements in a cost-effective manner. Due to their lightness, excellent corrosion and wear resistance along with superior thermo-mechanical properties, FRPs have emerged as one of the best alternatives in the field of civil infrastructure. This paper covers several aspects of the design, manufacturing, testing, analysis, and field implementation of a novel integrated FRP wicket gate in Mississippi River lock and dam. The cellular FRP panel with foam core and integrated stiffening and fastening components has been analyzed to compute the bending stiffness both theoretically and experimentally and a good correlation has been obtained.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.