Method and device for improving ductility of FRP (fiber reinforced plastic) strengthened structure and increasing FRP utilization rate

Abstract

The invention discloses a method and a device for improving the ductility of an FRP (fiber reinforced plastic) strengthened structure and increasing an FRP utilization rate. The device is characterized in that the FRP strengthened structure comprises end anchor devices, an FRP sheet, expansion bolts and a binder, wherein each end anchor device is processed from a low-carbon steel plate, an anchor section, a deformation section and a connection section are arranged on the end anchor device, the width of the deformation section is variable, and the ultimate strength of the deformation section is lower than that of the FRP sheet. The method comprises the following steps: two pre-punched holes are formed in a strengthening area of to-be-strengthened concrete; the binder is applied to the strengthening area of the to-be-strengthened concrete; the end anchor devices and the FRP sheet are adhered to the binder; the expansion bolts penetrate round holes in the end anchor devices and are pressed into the pre-punched holes. By means of the end anchor devices, the ductility of the FRP strengthened structure is improved, the FRP utilization rate is increased, and the conventional problem of brittle failures is solved.

Description

technical field [0001] The invention relates to the field of FRP reinforcement, in particular to a method and a device for improving the ductility of FRP reinforced structures and the utilization rate of FRP. Background technique [0002] Fiber Reinforced Polymer / Plastic (FRP) is widely used in structural reinforcement due to its outstanding advantages such as light weight, high strength, corrosion resistance, and convenient processing. At present, the most widely used and most in-depth research in the world is the external FRP reinforcement technology, also known as EB-FRP reinforcement technology. The method of EB-FRP reinforcement technology is to directly paste the FRP sheet to the structure to be reinforced with epoxy resin, so that the load on the structure will be transferred to the FRP material through the epoxy resin adhesive, so that the FRP Share the unbearable load for the original structure, and achieve the effect of reinforcement through this method. It is no...

AI Technical Summary

Problems solved by technology

However, a large number of current experimental studies have shown that the FRP-concrete bond interface is relatively fragile, and it is very consistent in the peeling failure with the typical failure form of FRP peeling from the concrete.

There are significant disadvantages in this destruction: (1) FRP utilization rate is low, and FRP will be peeled off from the concrete interface when only reaching about 30% utilization rate, which is a huge problem for FRP materials with very high strength. waste, but also increases the economic cost; (2) the ductility is poor, and the failure mode belongs to brittle failure

In view of this, this patent will propose a method and device to improve the ductility of FRP structures and FRP utilization to solve the existing brittle failure problems

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