Test device and method for measuring axial compression performance of composite material pipe for structural engineering

Abstract

The invention relates to a test device for measuring the axial compression performance of a composite material pipe for structural engineering. The test device is characterized by comprising an upper end plate, a lower end plate, a semicircular steel bar, an axial strain gauge and an annular strain gauge, the upper end plate and the lower end plate are the same in structure, each of the upper end plate and the lower end plate comprises a circular end plate and a cylindrical bulge positioned in the center of the end plate, the two semicircular steel bars are fixed on the end plates through glue, an annular groove is formed between the two semicircular steel bars and the cylindrical bulge, and the groove is used for accommodating the end part of a tubular compression sample; the groove is filled with high-strength gypsum to fix the end part of the sample with the end plate; the axial strain gauge and the annular strain gauge are uniformly distributed on the outer surface of the sample around the circumference of the sample and are positioned in the middle of the sample. The invention further relates to a test method for measuring the axial compression performance of the composite material pipe for structural engineering. The device is simple in structure, flexible and convenient in test method operation, wide in applicability and high in detection precision, and belongs to the technical field of structural material performance detection in civil engineering.

Description

technical field [0001] The invention relates to a performance detection technology of structural materials in civil engineering, in particular to a test device and a test method for measuring the axial compression performance of composite material pipes for structural engineering. Background technique [0002] Fiber Reinforced Polymer (FRP), as a new type of material, has excellent properties such as high strength and good corrosion resistance. It has been widely used in the field of civil engineering in recent years, and the most typical application is fiber reinforcement. The composite material pipe (hereinafter referred to as: composite material pipe) confines the concrete. The composite pipe can be made by hand by wet laying of fiber cloth, or directly by pultrusion or fiber winding. Under the action of axial pressure, the lateral expansion of concrete can be effectively restrained by the fibers arranged close to the hoop, thus greatly improving the strength and ductili...

AI Technical Summary

Problems solved by technology

The former is to embed the end of the circular tube into the groove of the end plate, and then pressurize the sample through the end plate, but because the groove of the end plate is very narrow, it is difficult to adapt to the diameter of the industrially produced fiber-wound tube. fluctuations and changes in wall thickness, and the test device is difficult to reuse; while the latter is to directly pressurize the sample after the end of the tubular sample is reinforced, but this method is only applicable to nominal diameters of 50-100mm, Composite tubes with a ratio of diameter to reinforced thickness not greater than 50

[0005] In addition, in view of the obvious nonlinearity in the axial direction of the composite pipe used in structural engineering under the two-way stress state, there is no directly applicable measurement method and expression method at home and abroad.

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