A Method for Measuring the Impact Load of Thin-walled Beams with Double Symmetrical Section Openings

Abstract

The invention discloses a method for measuring the impact load of a thin-walled beam with an open double symmetrical section, comprising the following steps: S1. Establishing a coordinate system: selecting the centroid of the cross section of a thin-walled beam with a double symmetrical cross section as the coordinate origin o, and the x axis along one of the symmetrical axes To the right, the y-axis goes up along another symmetrical axis, and the direction of the z-axis is determined according to the right-hand rule; S2. Measure the strain of each strain rosette on a certain cross-section of a double-symmetrical open thin-walled beam. According to the linear elastic superposition theory, the The measured strains are superimposed, and the stress value corresponding to the impact load is calculated to obtain; S3, according to the stress value calculated in step S2, the impact load on the section is calculated. The invention solves the problem of load measurement when the open thin-walled beam with double symmetrical section is impacted, the measurement result is true and reliable, and reliable impact load data can be provided for simulation calculation.

Description

technical field [0001] The invention relates to the technical field of load measurement of aircraft design mechanical structures, in particular to a method for measuring the impact load of a thin-walled beam with double symmetrical cross-section openings. Background technique [0002] Because the open thin-walled members have the characteristics of light weight, high rigidity, good force and easy manufacturing, open thin-walled beams are widely used in industrial production, especially open thin-walled beams with double symmetrical cross-sections, such as H-shaped steel, I-beam, and housing. Beams, car frames, engine piston rods, etc. These structures may be damaged by large impact loads. If the impact loads of these structures could be measured, it would facilitate structural optimization design. The current method for measuring loads in laboratories is to use force sensors and force measuring platforms, which are accurate for static loads or low-frequency dynamic loads, ...

AI Technical Summary

Problems solved by technology

The current method of measuring load in the laboratory is to use force sensors and force measuring platforms, which are accurate for static loads or low-frequency dynamic loads, but cannot be measured with force sensors and force measuring platforms for impact loads

Chinese patent zl201711231744.4 discloses a method for measuring the impact load of a beam with a double symmetrical section. Since this method does not consider the constrained torsional wave of a thin-walled beam with a double symmetrical section opening, the measurement effect on the torsional wave of a thin-walled beam with a double symmetrical section opening is poor.

Chinese patent zl201510005411.4 discloses a method for identifying the impact load of fan blades. Since this method measures the frequency response function, which is a quasi-static measurement method, it cannot measure the stress wave on the structural parts.

Chinese patent zl201410018879.2 discloses a load measuring device and its measuring method, the measuring device is only suitable for static load and quasi-static load measurement

[0003] In short, the existing measurement methods are still difficult to meet the measurement of the impact load of thin-walled beams with double symmetrical cross-section openings

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