SMA-GFRP (Styrene Maleic Anhydride-Glass Fiber Reinforced Plastics) hyperelastic composite bar and manufacturing method thereof

Abstract

The invention relates to an SMA-GFRP (Styrene Maleic Anhydride-Glassfiber Reinforced Plastics) hyperelastic composite bar and a manufacturing method thereof. The manufacturing method of the SMA-GFRP hyperelastic composite bar comprises the following specific steps: a, placing extremely-fine SMA filaments which are 24 percent in volume percentage and are 0.5mm in diameters and 44 percent of GFRP tows in parallel or annularly, and curing a flexible vinyl ester resin matrix between two kinds of fibers through a pultrusion process, wherein the volume percentage of the flexible vinyl ester resin matrix is 32 percent, and a section is a circle being the same as a steel bar through molding of the pultrusion process; b, deforming the surface of the SMA-GFRP bar or performing sand burning treatment on the surface to enhance anchoring between the SMA-GFRP and concrete. The SMA-GFRP hyperelastic composite bar has high ductility and corrosion resistance, and the problem of limited use of the GFRP bar in an anti-earthquake structure is solved; when the SMA-GFRP composite bar is applied to a plastic hinging area, the anti-earthquake performance of a structure is enhanced, residual displacement accumulation after continuous earthquakes is reduced, and the integral performance of the structure after continuous earthquakes is improved.

Description

technical field [0001] The invention belongs to the field of building and civil engineering materials, and in particular relates to a SMA-GFRP superelastic composite bar and a preparation method thereof. Background technique [0002] Traditional reinforced concrete structures mainly use steel bars as reinforcing bars, but many years of practical experience have found that steel bars have the following disadvantages: First, the corrosion of steel bars is very serious, especially in structures in coastal areas such as oceans and ports. The bearing capacity of the structure is greatly reduced, and the expected service life cannot be achieved, and the huge maintenance and renovation costs cause a waste of resources; second, the excessive deformation of the steel bar after yielding will lead to permanent residual displacement of the structure, making the overall bearing capacity of the structure reduce. Especially when an earthquake occurs, the permanent plastic deformation of s...

AI Technical Summary

Problems solved by technology

At present, the SMA-GFRP superelasticity made by mixing Ni-Ti SMA filaments, GFRP tows and resin matrix (superelasticity: refers to the strain that is much greater than the elastic limit strain of the sample under the action of external force, and the The phenomenon that the strain can be automatically restored with time) composite bars and their preparation methods have not been reported, and the optimal fiber mixing ratio of the three is the core of the research

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