Method and device for cable force test in unknown boundary condition

Abstract

The invention relates to the technical field of cable force tests when boundary is unknown, and especially relates to a method and a device for a cable force test in an unknown boundary condition. The method comprises: taking a part from a pretest test structure, using the part as a substructure unit; arranging a plurality of test points at interval on the substructure unit, each test point being provided with an acceleration sensor, the test point obtaining vibration data through the acceleration sensor; based on the vibration data, through modal analysis, obtaining a vibration mode curve of the substructure unit, and extracting the vibration mode amplitude of each test point from the vibration mode curve; and according to the amplitude, combining with vibration frequency f corresponding to the vibration mode curve and known parameters of the test structure, solving the cable force T of the test structure. The cable force test method realizes cable force tests on a test structure whose boundary condition is unknown and cable pole calculation length is unknown. In the cable force test process, the method gives full consideration on influence of flexural rigidity of the test structure, so the obtained cable force is more accurate, and the device can the method can preferably satisfy actual measuring requirements of cable force tests.

Description

Technical field [0001] The invention relates to the technical field of cable force testing when the boundary is unknown. Specifically, it relates to the cable-stayed bridge cable, arch bridge suspender, arch bridge tie rod, suspension bridge main cable and suspender, bridge prestressed steel strand and other structures Cable force testing method and device. Background technique [0002] Cable-stayed bridge’s stayed cables, tied arch bridge suspenders and flexible tie rods, suspension bridge’s main cables and suspenders, external prestress, etc., such structures, as the main force-bearing members of the bridge, what is the stress situation? , Not only need to be considered in the design stage, but also to be tested during use. The current cable force measurement methods mainly include: ① oil pressure gauge reading method; ② sensor reading method; ③ vibration method. Among them, the oil pressure gauge reading method and the sensor reading method have intuitive advantages, but the...

AI Technical Summary

Problems solved by technology

[0017] However, in actual engineering, the test structure is affected by various conditions, and the boundary conditions at both ends are not simply supported or fixed in theory. Even if the boundary conditions are determined, in many cases, there may not be an explicit analytical solution.

It can be seen that the above-mentioned method of testing the cable force of the cable-strut based on the beam theory is not suitable for the measurement of the cable force of the test structure with unknown boundary conditions and unknown cable-strut calculation length.

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