Steel-concrete interface shear force connecting piece fatigue performance test apparatus and application method thereof

Abstract

The invention discloses a steel-concrete interface shear force connecting piece fatigue performance test apparatus and an application method thereof. The apparatus comprises a lower clamp, an upper clamp, pressure plates, a positioning cylindrical pin, lateral set bolts, height adjusting bolts, spherical bolts and pads; the lower clamp is provided with a groove used for accommodating a test piece; the upper surface of a steel plate are arranged on the upper surface of the lower clamp through the pressure plates and the height adjusting bolts; the steel plate is compacted by the lateral set bolts; the pads comprise a left push plate and a right pull plate, and are arranged at two sides of concrete and clinging to the test piece; the upper clamp is arranged above the lower clamp according to the positions of the pressure plates and the test piece, and the handle position of the upper clamp aligns at the handle position of the lower clamp to guarantee the centers of the handles being in the interface of the test piece, that is a shear surface; he lower clamp is provided with the positioning cylindrical pin; and the left and right spherical bolts are screwed to make the push plate and the pull plate respectively cling to the left side surface and the right side surface of the test piece. Influences of eccentric loading can be corrected in the invention to obtain the fatigue performance of the shear force connecting piece under cycle load.

Description

technical field [0001] The invention relates to a test device and an application method for measuring the fatigue performance test of a shear connector between steel and concrete interfaces. Background technique [0002] At present, the push-out test is generally used to test the shear force transfer between steel and concrete. When the push-out test is used to study the shear strength of the shear connectors and the fatigue performance under cyclic loading, if all the shear connectors in the test piece can be ensured The stresses are equal and loaded synchronously, and the test results can accurately reflect the mechanical performance of each shear connector. However, the test loading and the specimen itself are affected by many random factors, such as the deviation of the specimen, the compactness of the concrete around the shear connector, the deviation of the welding position of the shear connector, the difference in welding quality, the loading eccentricity and The def...

AI Technical Summary

Problems solved by technology

However, due to the influence of many random factors on the test loading and the specimen itself, such as the manufacturing deviation of the specimen, the compactness of the concrete around the shear connector, the deviation of the welding position of the shear connector, the difference in welding quality, the loading eccentricity and The deflection of the interface caused by reciprocating loads, etc., makes it difficult to ensure that the loads on each shear connector are exactly equal

At the same time, the requirements of the pressure testing machine and the huge size of the push-out test piece make the push-out test often limited by the test equipment, test site and funds

[0003] When the test piece is released to test the influence of the corrosion of the shear connector on its fatigue performance, due to the concrete material properties, current density, etc., it is difficult to ensure that the corrosion degree of each shear connector is the same, and different corrosion degrees lead to poor stress. Uniformity, so that the heavily corroded shear connectors bear larger loads and break faster, which affects the ultimate bearing capacity, making it difficult to accurately judge the true bearing capacity of the corroded shear connectors

Moreover, the overall mass of the test piece is too large, so that the accuracy of the weighing instrument that meets the range is relatively rough, and it is difficult to use the weighing method to measure the loss of corrosion mass

It is therefore difficult to accurately measure the effect of corrosion on the fatigue performance of shear connectors at the steel-concrete interface

The invention patent application CN102879282A of our institute discloses a test piece and test method, but it is limited to monotonic loading, and cannot be subjected to cyclic loading, and cannot perform fatigue mechanical performance testing of shear connectors

At present, there is no test device for reciprocating cyclic loading

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