Unlock instant, AI-driven research and patent intelligence for your innovation.

A damage identification method for beam structures based on support reaction force and inclination slope

A technology for bearing reaction force and damage identification, which is used in the testing of machine/structural components, elasticity testing, instruments, etc., and can solve the problems of complex structural damage identification and calculation.

Active Publication Date: 2021-02-09
XIANGTAN UNIV
View PDF8 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0003] Structural damage identification technology based on static parameters is more researched index based on deflection, static strain and support reaction force influence line index, etc., but structural damage identification calculation based on parameters such as deflection, static strain and support reaction force more complex

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • A damage identification method for beam structures based on support reaction force and inclination slope
  • A damage identification method for beam structures based on support reaction force and inclination slope
  • A damage identification method for beam structures based on support reaction force and inclination slope

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0110] Embodiment one: see Figure 15 , the span of the simply supported beam is 100cm, and a unit is divided by 5cm, with a total of 20 units and 21 measuring points (the number in the upper circle in the figure is the unit number, and the lower number is the measuring point number). The cross-sectional size of the plate is b×h=4.5cm×1.5cm, and the elastic modulus of the material is 2.7×10 3 MPa, Poisson's ratio is 0.37, density is 1200kg / m 3 .

[0111] The damage in the actual engineering structure, such as the generation of cracks, material corrosion or the reduction of elastic modulus, generally only causes a large change in the structural stiffness, but has little impact on the quality of the structure. Therefore, in the finite element calculation, it is assumed that the damage of the structural element only causes the decrease of the stiffness of the element, and does not cause the change of the mass of the element. Damage to elements is simulated by a reduction in th...

Embodiment 2

[0121] Embodiment two: see Figure 20 , the span of the cantilever beam is 100cm, and a unit is divided by 5cm. There are 20 units and 21 measuring points in total (the numbers in the upper circle in the figure are unit numbers, and the numbers in the lower row are measuring point numbers). The cross-sectional size of the plate is b×h=4.5cm×1.5cm, and the elastic modulus of the material is 2.7×10 3 MPa, Poisson's ratio is 0.37, density is 1200kg / m 3 .

[0122] Considering that the fixed support end unit 1, the mid-span unit 10, and the free end unit 20 have different degrees of damage, the damage conditions are shown in Table 2.

[0123] Table 2 Multiple damage conditions of the cantilever beam

[0124]

[0125] The specific implementation steps are as follows:

[0126] Step 1: Apply a concentrated load of 10N to the No. 21 measuring point at the cantilever end of the damaged cantilever beam to obtain the measured inclination curve of the damaged cantilever beam, and th...

Embodiment 3

[0132] Embodiment three: see Figure 25 , the span layout of the three-span continuous beam is 100+150+100cm, and 10cm is divided into one unit, a total of 35 units and 36 measuring points (the numbers in the upper circle in the figure are the unit numbers, and the lower numbers are the support numbers) . The cross-sectional size of the plate is b×h=4.5cm×1.5cm, and the elastic modulus of the material is 2.7×10 3 MPa, Poisson's ratio is 0.37, density is 1200kg / m 3 .

[0133] Unit 7 is located near the point 0 of the side span bending moment under uniform load, unit 13 is located near the point 0 of the bending moment under concentrated load in the middle span, unit 18 is the mid-span unit of the middle span, and unit 26 is the maximum negative moment unit of the third span. The damage conditions are shown in Table 3.

[0134] Table 3 Damage conditions of three-span continuous beams

[0135]

[0136] The specific implementation steps are as follows:

[0137] Step 1: Ap...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

PUM

No PUM Login to View More

Abstract

The invention discloses a beam structure damage identification method based on support reaction force and inclination angle slope. The steps are as follows: apply load to the damaged beam structure to obtain the measured inclination angle curve and support reaction force; calculate the slope of the measured inclination angle curve ;Calculate the bending moment value at each position of the beam structure through the support reaction force and load; divide the bending moment value by the inclination slope to obtain the stiffness of each position, and identify the damage position through the sudden change of the stiffness curve in the damage state; remove the stiffness of the damage position, and calculate the remaining Fit the stiffness curve to obtain the stiffness curve in the undamaged state; calculate the damage degree from the stiffness curves in the damaged and undamaged states, and obtain the structural stiffness of the beam at the damaged position; For different positions of the beam structure, the damage position, damage degree and stiffness results under multiple loads are obtained, and the damage judgment is comprehensively carried out. The invention can accurately locate and quantitatively analyze the damage of the beam structure, and is applied to the damage assessment of the beam structure.

Description

technical field [0001] The invention belongs to the field of beam structure health monitoring, and in particular relates to a beam structure damage identification method based on support reaction force and inclination slope. Background technique [0002] In recent years, there are more and more old bridges in our country, and the problems are becoming more and more obvious. Many existing bridges can no longer meet the functional requirements, and safety accidents such as bridge breakage and collapse occur from time to time. Scholars in the field of civil engineering have gradually realized the importance of health monitoring and safety assessment of bridge structures, and have studied various damage identification technologies. . Structural damage identification is an important part of the bridge structural health monitoring system. At present, there are two main types of damage identification methods. One is the damage identification method based on dynamic parameters, whi...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

Application Information

Patent Timeline
no application Login to View More
Patent Type & Authority Patents(China)
IPC IPC(8): G01M99/00G01M5/00
CPCG01M5/0008G01M5/005G01M99/00G01M99/007
Inventor 唐盛华刘宇翔张学兵秦付倩杨文轩成鹏张佳奇
Owner XIANGTAN UNIV