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Detection method of absolute stress distribution of steel members based on critically refracted longitudinal waves

A technology of critical refraction and stress distribution, applied in the direction of measuring force, measuring devices, instruments, etc., can solve the problems of inaccurate stress results and constraints on the research and application of absolute stress of ultrasonic detection components

Active Publication Date: 2019-10-25
HARBIN INST OF TECH SHENZHEN GRADUATE SCHOOL
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  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, the stress detected by the ultrasonic method is the average stress on the sound path of the ultrasonic wave. For components with a large stress gradient, the results of using the ultrasonic method to detect stress are not accurate, which restricts the research and application of the absolute stress of components using ultrasonic testing.

Method used

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  • Detection method of absolute stress distribution of steel members based on critically refracted longitudinal waves
  • Detection method of absolute stress distribution of steel members based on critically refracted longitudinal waves
  • Detection method of absolute stress distribution of steel members based on critically refracted longitudinal waves

Examples

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Effect test

Embodiment 1

[0071] The following is a principle explanation of the detection method of the absolute stress distribution along the axial direction of steel members based on critical refracted longitudinal waves.

[0072] Consider construction steel member materials as isotropic bodies. When the critically refracted longitudinal wave propagates a section of sound path L in the steel member, the method detailed in the patent document 201410181350.2 can be used to detect the average stress of the sound path of L section, which can be solved by the following formula:

[0073] σ=B(t 0 -t) (3)

[0074] In formula (3), σ is the absolute stress of steel members in service, in MPa; B is the stress-acoustic time difference coefficient, in MPa / ns; t 0 The unit is ns when critically refracted longitudinal wave reproduces sound propagation of a certain sound path of a steel member; t is the propagating sound of a critically refracted longitudinal wave on a certain sound path of an in-service steel me...

Embodiment 2

[0090] The detection method of the absolute stress distribution of steel members along the axial direction based on the critical refraction longitudinal wave is used for the test and verification of the absolute stress distribution of steel members.

[0091] A steel plate is selected as the test object. In order to generate stress fields with different stress value distributions, the design and fabrication of such image 3 The test piece A shown, the material of the test piece A is No. 45 steel, and the size of the test piece A is as follows Figure 4 shown. In order to fit the stress-acoustic time difference coefficient under different sound paths, the following Figure 5 The test piece B shown, the material of the test piece B is 45# steel, and the size of the test piece B is as follows Figure 6 shown.

[0092] According to the steps in Example 1, the absolute stress distribution of the steel member along the axial direction is detected.

[0093] The first step is to c...

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Abstract

The invention discloses a steel member absolute stress distribution detection method based on critical refraction longitudinal waves. Through calibrating a stress-sound time difference coefficient of the critical refraction longitudinal waves on a sonic path distance of a steel member, a single-emission and double-receiving sensor set is employed to detect the sound propagation time on the corresponding sonic path distance of the in-service steel member, an absolute stress of the steel member is solved, and axial distribution of the absolute stress of the steel member is acquired; the single-emission and double-receiving sensor set comprises an emission sensor and two receiving sensors. The method is advantaged in that damageless detection on axial distribution of the absolute stress of under-construction and well-constructed steel members can be realized, test on a local absolute stress of the in-service steel member can be realized, absolute stress distribution of the in-service steel member can be acquired, and stress distribution of a region of the in-service steel member having relatively large absolute stress gradient can be especially accurately tested.

Description

technical field [0001] The invention belongs to the field of non-destructive detection of absolute stress of steel components, in particular to a detection method of absolute stress distribution of steel components based on critical refraction longitudinal waves. Background technique [0002] In order to adapt to economic and social development, my country has built many steel structures such as long-span bridges, high-rise buildings and large-span spaces. These structures have large investment, complex structure, and harsh service environment. During their construction and long-term service, they will suffer from environmental erosion, fatigue load, strong / typhoon, earthquake, flood / torrential rain and other disasters, and their spatial stress state will occur. This will have a negative impact on the safety of steel structures. Once these structures fail, they will bring huge direct and indirect economic losses and adverse social impacts. Therefore, the research on the abs...

Claims

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Application Information

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Patent Type & Authority Patents(China)
IPC IPC(8): G01L1/25
CPCG01L1/255
Inventor 李祚华何京波杨晨滕军
Owner HARBIN INST OF TECH SHENZHEN GRADUATE SCHOOL
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