Flexural Behavior of Polyurethane Concrete Reinforced by Carbon Fiber Grid

Abstract

In view of the problems of traditional repair materials for anchorage concrete of expansion joints, such as ease of damage and long maintenance cycles, the design of polyurethane concrete was optimized in this article, which could be used for rapid repair of concrete in anchorage zone of expansion joints. A new type of carbon fiber grid–polyurethane concrete system was designed, which makes the carbon fiber grid have an excellent synergistic effect with the quick-hardening and high-strength polyurethane concrete, and improved the flexural bearing capacity of the polyurethane concrete. Through the four-point bending test, the influence of the parameters such as the number of grid layers, grid width, and grid density on the flexural bearing capacity of polyurethane concrete beams was tested. The optimum preparation process parameters of carbon fiber grid were obtained to improve the flexural performance of polyurethane concrete. Compared with the Normal specimen, C-80-1’s average flexural strength increased by 47.7%, the failure strain along the beam height increased by 431.1%, and the failure strain at the bottom of the beam increased by 68.9%. The best width of the carbon fiber grid was 80 mm, and the best number of reinforcement layers was one layer. The test results show that the carbon fiber grid could improve the flexural bearing capacity of polyurethane concrete. The carbon fiber grid–polyurethane concrete system provides a new idea for rapid repair of the anchorage zone of bridge expansion joints, and solves the problems such as ease of damage and long maintenance cycles of traditional repair materials, which can be widely used in the future.

Glass Fibers Reinforced Concrete: Overview on Mechanical, Durability and Microstructure Analysis

“…When 0.1 percent glass fibers are added to conventional concrete, FLS increases by 19.31 percent after 28 days [ 57 ]. The FLS of the specimens reinforced by carbon-fiber grid and steel-strand grid increased by 47.7% and 13.3%, respectively, as compared to the normal specimen [ 58 ]. When the FLS of concrete containing 1% polyethylene terephthalate is compared to the FLS of control concrete, the FLS of the control concrete improves by 20% [ 59 ].…”

Development and Characterization of a Sustainable Bio-Polymer Concrete with a Low Carbon Footprint

“…Compared with conventional cement-based concrete, PC has several advantages, including low permeability, chemical resistance, high ductility, high mechanical strength, and excellent bonding with other types of surfaces [ 13 ]. Therefore, PC in infrastructure applications offers high-performing solutions, such as enabling a faster return to service due to its fast-setting time and improved flexibility, versatility, and durability, reducing the need for frequent repairs required by conventional concrete [ 14 ]. The main applications of PC in infrastructure include bridge decks, industrial overlays, pavements, wastewater pipes and containers, utility holes, underground communication and transmission line boxes, building façade panels, and machine foundations [ 15 , 16 , 17 ].…”

Investigation of Interfacial Bonding Properties of Polyurethane Concrete and Cement Concrete/Steel Reinforcement

“…In summary, polyurethane concrete has the characteristics of high strength, corrosion resistance, and excellent fatigue performance [10]. Compared with conventional cement concrete, polyurethane concrete has good dynamical performance [23].…”

“…Polyurethane concrete is a novel composite material prepared by polyurethane binder, gravel aggregate, additives, etc. [10]. Nikoukalam et al [11] tested the basic mechanical properties of polyurethane concrete and analyzed the mechanical response characteristics under various loading conditions.…”

“…Polyurethane concrete also possesses a certain temperature sensitivity and exhibits different mechanical properties at different temperature conditions [17][18][19]. e specimen undergoes brittle damage at low temperatures and plastic damage at high temperatures [10].…”