Looking for breakthrough ideas for innovation challenges? Try Patsnap Eureka!

Method for detecting mechanical strength of heat-treated wood

A technology of mechanical strength and detection method, which is applied in the field of non-destructive testing of mechanical strength of heat-treated wood, and the detection of mechanical strength of heat-treated wood, can solve problems such as damage to wood samples, loss of mechanical strength of wood, and large amount of repeated samples.

Pending Publication Date: 2021-02-09
NORTHWEST A & F UNIV
View PDF3 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

The defect of high-temperature heat treatment of wood is mainly to reduce the mechanical properties of wood, especially when the heat treatment temperature is higher than 200°C, the mechanical strength of wood will be seriously lost, which greatly affects the use of wood products.
[0004] However, the mechanical strength test of wood is a destructive test, which will cause irreversible damage to the wood sample, and the test is time-consuming and increases the test cost.
Because of the anisotropy of wood, the number of repeated samples required for mechanical property testing is large. For some specimens with precious species and few samples, testing its mechanical strength becomes a major problem.

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
  • Method for detecting mechanical strength of heat-treated wood
  • Method for detecting mechanical strength of heat-treated wood
  • Method for detecting mechanical strength of heat-treated wood

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0061] A poplar tomentosa specimen with a size of 20mm(R)×100mm(T)×390mm(L) was selected, nitrogen was used as a protective gas, the heat treatment temperatures were 180°C, 200°C and 220°C, and the heat treatment time was 2h and 4h respectively , 6h, 8h, 10h, select 10 pieces of wood for each group, select 9 points on the surface of the specimen after heat treatment, use visible light spectrophotometer to measure CIE (1976) L*, a*, b* value, and take the average of the measurement results value.

[0062] Finally, process each heat treatment specimen with a size of 20mm(R)×100mm(T)×390mm(L) into two test pieces with a size of 20mm(R)×20mm(T)×300mm(L), refer to the national The standard GB / T1936.2-2009 "Test method for flexural modulus of elasticity of wood" measures the flexural modulus of elastic modulus of treated wood, and takes the average value of the measurement results. The color parameters and flexural modulus of each group are trained and learned by the support vector...

Embodiment 2

[0064] A poplar tomentosa specimen with a size of 20mm(R)×100mm(T)×390mm(L) was selected, nitrogen was used as a protective gas, the heat treatment temperatures were 180°C, 200°C and 220°C, and the heat treatment time was 2h and 4h respectively , 6h, 8h, 10h, select 10 pieces of wood for each group, select 9 points on the surface of the specimen after heat treatment, use visible light spectrophotometer to measure CIE (1976) L*, a*, b* value, and take the average of the measurement results value.

[0065] Finally, process each heat treatment specimen with a size of 20mm(R)×100mm(T)×390mm(L) into two test pieces with a size of 20mm(R)×20mm(T)×300mm(L), refer to the national The standard GB / T1936.1-2009 "Test method for flexural strength of wood" measures the flexural strength of treated wood, and the measurement results are averaged. Use the support vector machine model to train and learn the color parameters and bending strength of each group, and then substitute the color par...

Embodiment 3

[0067] A poplar tomentosa specimen with a size of 20mm(R)×100mm(T)×390mm(L) was selected, nitrogen was used as a protective gas, the heat treatment temperatures were 180°C, 200°C and 220°C, and the heat treatment time was 2h and 4h respectively , 6h, 8h, 10h, select 10 pieces of wood for each group, select 9 points on the surface of the specimen after heat treatment, use visible light spectrophotometer to measure CIE (1976) L*, a*, b* value, and take the average of the measurement results value.

[0068] Finally, each heat-treated specimen with a size of 20mm(R)×100mm(T)×390mm(L) is processed into two right-angled trapezoidal specimens with upper and lower bottoms of 30mm and 40mm respectively, referring to the national standard GB / T 1937- 2009 "Test Method for Shear Strength of Timber Along the Grain" Measure the shear strength of the treated wood, and take the average value of the measurement results. The color parameters and shear strength of each group are trained and lea...

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 method for detecting the mechanical strength of heat-treated wood, which is used for representing the mechanical strength of the heat-treated wood by measuring the color value of the heat-treated wood and realizing online nondestructive detection of the mechanical strength of the heat-treated wood. Specifically, a color mechanical strength characterization model is constructed by using a support vector machine, and the model construction process comprises the following steps of selecting a heat treatment wood test piece as a training group test piece, and measuring the color value and the mechanical strength of the training group test piece; constructing a heat treatment wood color mechanical strength characterization model based on a support vector machine; organizing a training sample set to train and learn the representation model; determining the color value of the test piece of the test group, organizing the test sample set, substituting into the characterization model, and calculating the mechanical strength; comparing the calculated mechanical strength with the actually measured mechanical strength, and adjusting parameters of the characterization model; and determining evaluation indexes of the characterization model. The method can realize on-line nondestructive detection of the mechanical strength of the heat-treated wood.

Description

technical field [0001] The invention belongs to the technical field of wood detection and relates to a non-destructive detection of the mechanical strength of heat-treated wood, in particular to a detection method of the mechanical strength of heat-treated wood. Background technique [0002] Wood is a renewable resource, because of its renewable, breeding, less investment, and non-polluting characteristics, more and more people pay attention to it, and the poor dimensional stability of wood is one of the main problems restricting its utilization. Warping and other deformations will seriously affect the processing and utilization of wood. Wood high-temperature heat treatment modification is a scientific, effective and widely used modification method to improve the dimensional stability of wood at this stage. It has the advantages of environmental protection, no need to add additional active chemical reagents, and relatively simple operation. [0003] Wood high-temperature he...

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
IPC IPC(8): G01N3/20G01N3/24G01N21/31G01N33/46G01N1/44
CPCG01N3/20G01N3/24G01N21/31G01N33/46G01N1/44G01N2203/0023G01N2203/0025
Inventor 雷亚芳王佳鹏闫丽陈爽毕振举佘丁辰
Owner NORTHWEST A & F UNIV
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Patsnap Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Patsnap Eureka Blog
Learn More
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic, Popular Technical Reports.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap|About US| Contact US: help@patsnap.com