A method for testing the pretension of membrane materials in existing membrane structures

Abstract

A method for detecting the pretension of membrane materials in existing membrane structures. This method involves locally releasing and restoring the pretension of the membrane material, and then using strain sensors to detect the pretension. It is a direct and highly accurate detection method.

Description

Technical Field

[0001] This invention relates to a method for detecting the pretension of membrane materials in existing membrane structures, particularly a non-destructive testing method that uses strain sensors to detect the pretension of membrane materials by partially releasing and restoring the pretension, which is intuitive and highly accurate. Background Technology

[0002] Currently, the prestress of existing membrane structures is mostly measured using Raman spectroscopy, vibration (frequency) testing, and displacement testing. These methods are theoretically complex, influenced by numerous factors, and have limited accuracy. Raman spectroscopy ignores the effect of the membrane coating, affecting accuracy, and the equipment used is expensive, limiting its practical application. Vibration (frequency) testing is greatly affected by boundary conditions, which are often very complex in actual engineering projects, resulting in low accuracy. Displacement testing requires pre-calibrating the prestress relationship curves for different membrane materials, which is extremely labor-intensive, and the calibration conditions often differ significantly from those in actual engineering projects, greatly impacting accuracy. Summary of the Invention

[0003] To overcome the shortcomings of methods such as Raman spectroscopy, vibration (frequency) testing, and displacement testing, this invention provides a more intuitive non-destructive testing method for the pretension of existing membrane materials. This method uses a testing device to release the local pretension of the existing membrane material, removes the testing device to restore the pretension of the membrane material, and then performs the measurement. It is intuitive, convenient, and highly accurate.

[0004] The technical solution adopted by the present invention to solve its technical problem is as follows: a detection device is installed at the sampling part of the membrane material of the existing membrane structure; the pretension of the membrane material in the area between the two sets of clamps is released by adjusting the distance between the two sets of clamps of the detection device; a strain sensor is installed on the surface of the membrane material after the pretension has been released; the detection device is removed to restore the pretension of the membrane material; the strain of the membrane material is measured by the strain sensor, and then its pretension is calculated.

[0005] The advantages of this invention are that it is intuitive, convenient, and highly accurate. Attached Figure Description

[0006] The invention will be further described below with reference to the accompanying drawings.

[0007] Figure 1 This is a structural schematic diagram of an embodiment of the present invention.

[0008] Figure 2 It is a top view.

[0009] Figure 3 It is the left view.

[0010] In the figure, (1) the membrane material to be tested, (2) the clamp of the testing device, (3) the adjusting screw of the testing device, and (4) the strain sensor. Detailed Implementation

[0011] exist Figure 1 In the process, the testing device holder (2) is installed on the surface of the membrane material (1) to be tested and clamps the membrane material. The testing device adjusting screw (3) is tightened to change the distance between the two testing device holders (2) so that the pretension of the local area of ​​the membrane material (1) to be tested between the two testing device holders (2) is completely released. The strain sensor (4) is installed, the testing device adjusting screw (3) is turned to the initial installation position, the testing device holder (2) is removed, and the pretension of the membrane material (1) to be tested is measured by the strain sensor (4).

Claims

1. A method for detecting the pre-tension of existing membrane structure membrane material, comprising: installing a detection device at a sampling point of the existing membrane structure membrane material; releasing the pre-tension of the membrane material in the area between the two sets of clamps by adjusting the distance between the two sets of clamps; installing a strain sensor on the surface of the membrane material after the pre-tension has been released; removing the detection device to restore the pre-tension of the membrane material; measuring the strain of the membrane material using the strain sensor; and then calculating its pre-tension. The method is characterized by: The existing membrane structure is released by releasing the local pretension of the membrane material using a detection device, and the measurement is performed after the pretension of the membrane material is restored.

Images