FRP rib fibre cloth winding coaxial connection method

Abstract

An FRP rib fibre cloth winding coaxial connection method comprises the steps of fixing reinforcement materials to be connected in a centring manner to ensure that the reinforcement materials cannot be slid and displaced, winding fibre cloth at the abutting-joint portion of the reinforcement materials to be connected so as to connect the reinforcement materials, winding fibre strand / band at the two ends of fibre cloth winding section and the intermediate joint, winding terylene film on the external surface of the well wound reinforcement material fibre cloth composite material, sealing the tail ends of the film, tripping off the terylene film after the resin is cured and finally finishing the coaxial connection. The connection method of the invention has a small size of connector lug, light weight, high intensity and corrosion resistance, and is simple and convenient for construction.

Description

technical field [0001] The invention belongs to the field of composite materials, and relates to a connection technology of composite materials, in particular to a coaxial connection method of FRP tendons. Background technique [0002] Cracks or micro-cracks will appear in the traditional reinforced concrete structure during use. When encountering sea water or salty snow water (sprinkling salt to form salty snow water for melting snow) or corrosive gas liquid, the steel bar will be corroded. , resulting in the decline or complete loss of the structural bearing capacity; when there is a high-frequency electromagnetic field around, the steel bars will generate heat due to the dual current effect, resulting in thermal stress and cracking of the concrete; widely used in water conservancy and hydropower projects, deep foundations, underground structures , slope stability, mine roadway support, etc. may be corroded due to the interaction with groundwater and the chemical compositi...

AI Technical Summary

Problems solved by technology

[0005] There are several ways to connect steel bars: lap joint, welding and mechanical connection, but because thermosetting FRP bars do not have weldability and cold bendability; although thermoplastic FRP bars can be welded, the essence is the welding of the matrix, which plays a major role. The load-bearing fibers cannot be welded, and the strength and stiffness of FRP tendons are anisotropic, and the extrusion strength and interlayer properties are weak. It is a brittle material, and there is no substantial yield deformation during failure, and the ability to redistribute loads Therefore, the connection methods suitable for steel bar connection such as welding, ribbed steel sleeve extrusion connection, steel bar taper thread connection, steel bar upsetting and rolling straight thread connection, molten metal filling sleeve connection, etc. are not suitable for FRP bars.

Lap-bonding connections can also be used in FRP-reinforced concrete structures, but it is clearly stipulated in the reinforced concrete specifications that no lap-bonding joints should be used for longitudinally stressed steel bars under axial tension and small eccentric tension; When the diameter of the steel bar is greater than 28mm and the diameter of the compression steel bar is greater than 32mm, it is not suitable to use lap joints; for components that need to be checked for fatigue, the longitudinal tensile steel bars must not use lap joints, etc. It is necessary to research and develop effective coaxial connection methods to meet the needs of practical engineering

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