Buckling of Woven Fabric_new
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Transcript of Buckling of Woven Fabric_new
BUCKLING OF WOVEN FABRICS
Crushed Or Bent Under A Weight Or Force
BUCKLING……… In engineering science, buckling is a failure
mode characterized by high compressive stress at the point of failure when it is more than the ultimate compressive stresses the material is capable of withstand
The mode of failure is also called ’Elastic inability’
It is very common phenomena when we are using the fabric as a garment
FABRIC BUCKLING....
The simplest form of fabric buckling is known as
PLATE BUCKLING
Woven fabrics and buckling
We will try to find out……
Simple model of woven fabric bucklingPossibilities of modification of simple modelGlimpse of 3d-fabric modeling using buckling model
EARLIER WORKs....Dahlberg, B., Mechanical Properties of
Textile Fabrics, Part II: Buckling,Textile Research Journal 1961 31: 94
Lindberg, J., Behre, B. and Dahlberg, B., Shearing and Buckling of Various Commercial Fabrics, Textile Research Journal 1961 31: 99
Lindberg, J., Dimensional Changes in Multi Component Systems of Fabrics: A Theoretical Study , Textile Research Journal 1961 31: 664
SIMPLE MODEL OF WOVEN FABRIC AND BUCKLING....Woven fabric consist of two regions..
We have to overcome the Frictional Couple ( ) to bend the fabric
1. Intersection region where yarns are in
tension
2. Region between two intersection where fibers of yarn are in tension
Grosberg, P., The Mechanical Properties of Woven Fabrics : Part II: The Bending of Woven Fabrics; Textile Res. J~36(3) (1966)
ELASTIC BUCKLINGEuler’s equation of critical load when both ends
are clamped
For this simply supported beamBending moment at A=Curvature at A =So…
Integrating this we get....
Behera,B. K., Hari, P. K., Woven Textile Structure: Theory and application; W. P. L., 2010
y
α x
P
P
A
B
O
s
φ
Now let..
Contd.…
So , at point O
And at point B
And
Substituting these values we get
y
α x
P
P
A
B
O
s
φ
Behera,B. K., Hari, P. K., Woven Textile Structure: Theory and application; W. P. L., 2010
At B, s=l/2, θ=0 ; l =Total length of beam
Contd.…
Now if α→0, k=0, F=π/2;
This gives the minimum critical load ( )
Now for compression
y
α x
P
P
A
B
O
s
φ
We KnowSo,
As, at B , ф=0, x=x/2)
Behera,B. K., Hari, P. K., Woven Textile Structure: Theory and application; W. P. L., 2010
So the fractional compression is:Contd.…
Load
P
l^2/B
Compression 1-x/l
10
9
Behera,B. K., Hari, P. K., Woven Textile Structure: Theory and application; W. P. L., 2010
IDEAL FABRIC BUCKLINGP
P
A
A’
αK →
M ↑
M0
The length will follow the elastic buckling
Grosberg, P., Swani, N.M., The Mechanical Properties of Woven Fabrics : Part III: The Buckling of Woven Fabrics; Textile Res. J~36 (1966)
IDEAL FABRIC BUCKLINGFor elastic buckling
So, P
P
A
A’
α
Now, total length of fabric is
This equation is a quadratic equation of can be solved for
different values of αIf
Grosberg, P., Swani, N.M., The Mechanical Properties of Woven Fabrics : Part III: The Buckling of Woven Fabrics; Textile Res. J~36 (1966)
P
P
A
A’
α
IDEAL FABRIC BUCKLING Compressed height of this fabric model…
will follow the elastic body equation
Total compressed height
Fractional compression ( )
Grosberg, P., Swani, N.M., The Mechanical Properties of Woven Fabrics : Part III: The Buckling of Woven Fabrics; Textile Res. J~36 (1966)
CLAMPED FABRIC BUCKLINGBuckling equations..
=
As we are considering the fabric ends are clamped during buckling, simple modification of these equations is
needed For clamped beam orSo, and
Grosberg, P., Swani, N.M., The Mechanical Properties of Woven Fabrics : Part III: The Buckling of Woven Fabrics; Textile Res. J~36 (1966)
RECOVERY FROM BUCKLING
Fabric starts recovering when bending moment reduced by
Grosberg, P., Swani, N.M., The Mechanical Properties of Woven Fabrics : Part III: The Buckling of Woven Fabrics; Textile Res. J~36 (1966)
BUCKLING CURVE….
Theoretical vs. Experimental Buckling curve
Theoretical Buckling Curve
Grosberg, P., Swani, N.M., The Mechanical Properties of Woven Fabrics : Part III: The Buckling of Woven Fabrics; Textile Res. J~36 (1966)
EFFECT OF VARIOUS PARAMETERS
Variation of Buckling load with gauge length
Grosberg, P., Swani, N.M., The Mechanical Properties of Woven Fabrics : Part III: The Buckling of Woven Fabrics; Textile Res. J~36 (1966)
Experimental and theoretical variation of hysteresis in
buckling
CottonWorstedWool/TeryleneWool/Acrylan
Experimental and Theoretical variation of % compression
remaining with M0
CottonWorsted
CROSS CHECKING OF MODEL….
Variation of Frictional resistance
between two methods
Variation of Bending rigidity
between two methodsGrosberg, P., Swani, N.M., The Mechanical Properties of Woven Fabrics : Part III: The
Buckling of Woven Fabrics; Textile Res. J~36 (1966)
SCOPE OF MODIFICATION….
Fabric initial curvature is zero…
P
P
A
A’
α
Effect of fabric weight…
NormallyThe effect of fabric
weight is neglected
because the ratio of weight to
bending rigidity is negligible
Direction of applied force…
Yarn and fiber properties…Modeling taking
various practical aspects…
NONLINER BUCKLING….Infinitely large initial bending rigidity of the fabric is removed by Huang’s bilinear bending rule.
If B*=0, then it follows the Grosberg, P., Swani N. M. Model
Anandjiwala , R. D. & Gonsalves, J. W., Nonlinear Buckling of Woven Fabrics Part I: Elastic and Nonelastic Casess; Textile Res. J~76:160 (2006)
NONLINER BUCKLING….
Anandjiwala , R. D. & Gonsalves, J. W., Nonlinear Buckling of Woven Fabrics Part I: Elastic and Nonelastic Casess; Textile Res. J~76:160 (2006)
Anandjiwala , R. D. & Gonsalves, J. W., Nonlinear Buckling of Woven Fabrics Part II: Recovery from Buckling and Experimental Verification; Textile Res. J~76:160 (2006)
Other Works on BUCKLING….Buckling of Woven Fabrics : Part I: Effect of Fabric WeightT. G. Clapp and H. Peng, Textile Research Journal, 1990:60:228
Buckling of Woven Fabrics : Part II: Effect of Weight and Frictional CoupleT. G. Clapp and H. Peng, Textile Research Journal, 1990:60:285
Buckling of Woven Fabrics : Part III: Experimental Validation of Theoretical ModelT. G. Clapp and H. Peng, Textile Research Journal, 1990:60:641
Buckling Analysis of woven Fabric Under Simple Shear along Arbitrary DirectionsY. T. Zhang and J. F. Xu, Textile Research Journal, 2002:72:147
BUCKLING & FABRIC…. Modeling and animating the
garments worn by virtual characters
DIAMOND BUCKLING TWIST BUCKLING
Decaudin, P., Thomaszewski, B., Cani ,M. P., Virtual Garments Based on Geometric Features of Fabric Buckling ; INRIA , April (2005)
Real fabric show that whatever the fabric thickness and the cylinder’s radius, the number of diamond patterns that appear around a cross-section of the cylinder is always an integer say n.
In their experiments with real fabric, n varies from 2 to 8 with a cylinder of a few centimeters of radius and different thickness of cloth
the height b of the diamond patterns is also related to the radius R and to the physical properties of the fabric λ
Cylindrical fabric of known radius R0 around a slightly smaller rigid cylinder and observe Diamond buckling and get the associated value n0 get λ
PARAMETERS…
Decaudin, P., Thomaszewski, B., Cani ,M. P., Virtual Garments Based on Geometric Features of Fabric Buckling ; INRIA , April (2005)
FABRIC MODLLING….
Decaudin, P., Thomaszewski, B., Cani ,M. P., Virtual Garments Based on Geometric Features of Fabric Buckling ; INRIA , April (2005)
Grosberg, P., Swani, N.M., The Mechanical Properties of Woven Fabrics : Part III: The Buckling of Woven Fabrics; Textile Res. J~36 (1966)
Decaudin, P., Thomaszewski, B., Cani ,M. P., Virtual Garments Based on Geometric Features of Fabric Buckling ; INRIA , April (2005)
Behera,B. K., Hari, p. K., Woven Textile Structure: Theory and application; W. P. L., 2010
Anandjiwala , R. D., Gonsalves, J. W., Nonlinear Buckling of Woven Fabrics Part I: Elastic and Nonelastic Cases ; Textile Res. J~76(2) (2006)
REFERENCES….
Thank YOU...
…Any Queries??