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

Composite material multi-nail and double-shear connection failure prediction method based on three-parameter characteristic curve

A characteristic curve, composite material technology, applied in the direction of using stable shear force to test material strength, using stable tension/compression to test material strength, etc., can solve the problem of not considering shear characteristic points and wrong limit load prediction results , misjudgment failure mode and other problems, to achieve the effect of improving structural design efficiency, avoiding structural design improvement work, and avoiding repeated futility

Inactive Publication Date: 2013-10-02
BEIHANG UNIV
View PDF2 Cites 10 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0007] The classical characteristic curve only passes through the tensile and compressive characteristic points, and does not consider the influence of the shear characteristic points. There are cases where the failure mode is misjudged and the ultimate load prediction result is completely wrong.

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
  • Composite material multi-nail and double-shear connection failure prediction method based on three-parameter characteristic curve
  • Composite material multi-nail and double-shear connection failure prediction method based on three-parameter characteristic curve
  • Composite material multi-nail and double-shear connection failure prediction method based on three-parameter characteristic curve

Examples

Experimental program
Comparison scheme
Effect test

Embodiment Construction

[0043] The specific implementation process will be further described in detail below in conjunction with the flow chart.

[0044] Such as figure 1 As shown, in the classical characteristic curve method, the tensile characteristic size and the compressive characteristic size are used to determine the classical characteristic curve of the cosine distribution form, and its expression is:

[0045] r c (θ) = r 0 +R t +(R c -R t )cosθ -90°≤θ≤90°

[0046] Among them, R t and R c are the tensile and compressive characteristic dimensions, respectively, determined by experiments. r0 is the radius of the key hole, and θ is the angle rotated counterclockwise from the longitudinal compression plane of the composite multi-nail double-shear connection to the tension plane. The failure mode of the connection structure is determined according to the position of θ: when 0°≤|θ|≤15°, it is extrusion failure; when 30°≤|θ|≤60°, it is shear failure; when 75°≤ When |θ|≤90°, it is tensile fa...

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 provides a composite material multi-nail and double-shear connection failure prediction method based on a three-parameter characteristic curve. The composite material multi-nail and double-shear connection failure prediction method comprises the following steps of: (1) designing and preparing a test piece of a tensile, compression and shear characteristic size test according to parameters of geometry, a material, a laying layer and the like of a multi-nail and double-shear connection key hole of a composite material; (2) carrying out a static-force tensile test to obtain a tensile fracture load of an opening laminated board, an extrusion fracture load of a carrying hole laminated board, and a shearing fracture load of the carrying hole laminated board; (3) calculating tensile, compression and shear characteristic sizes according to the fracture loads; (4) acquiring the three-parameter characteristic curve based on the tensile, compression and shear characteristic sizes, wherein the curve passes through a tensile characteristic point, an extrusion characteristic point and a shearing characteristic point of the key hole; and (5) predicating a failure mode and a fracture load of a multi-nail and double-shear connection structure of the composite material based on the three-parameter characteristic curve. The composite material multi-nail and double-shear connection failure prediction method disclosed by the invention is applicable to multi-nail and double-shear connection failure prediction of the composite material in engineering application, and the failure mode and the fracture load of the connection structure can be accurately predicated by considering the shearing characteristic size.

Description

technical field [0001] The invention relates to failure prediction of composite material multi-nail double-shear connection structure, and is suitable for composite material multi-nail double-shear connection structure widely used in aerospace vehicles. Background technique [0002] The connection structure of advanced composite materials is the weak link in the overall structure of composite materials, and its strength directly affects the bearing capacity of the overall structure of composite materials. Composite material connections are mainly divided into adhesive connections and mechanical connections. Mechanical connections are further divided into single-shear connections and double-shear connections. The double-shear connections can withstand larger loads due to the absence of eccentric bending moments and have wider applications. At present, in the main load-bearing structure of composite materials of aircraft, mechanical connection is still the main connection meth...

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): G01N3/08G01N3/24
Inventor 张建宇刘丰睿赵丽滨山美娟
Owner BEIHANG 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