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Design & Analysis
Computer Programs
Beams:

Composite box beams including transverse shear effects. Composite I-beams. Including transverse shear effects.

Plates:

Circular - Sandwich and isotropic plates with central loading, self-weight, and uniform pressure. Includes transverse shear effects.

Rectangular:

  • Isotropic with uniform pressure or hydrostatic loads.
  • Sandwich with uniform pressure or hydrostatic loads including transverse shear effects.
  • Buckling for axial loads for isotropic and sandwich plates including transverse shear effects.
  • Stiffener requirements for uniform pressure or hydrostatic loads.

Cylinders:

  • Knuckle discontinuity analysis.
  • Buckling of isotropic and sandwich shells due to external pressure, lateral pressure, axial load, bending or combined loads. Materials can be isotropic or orthotropic. Laminated plate theory and classical shell theory are used. Results are per ASME RTP-1, ASME Section X, and NASA SP8007.
  • Half round and trapezoidal stiffener sizing for vacuum loading.
  • Composite cylinder analysis using classical laminated plate theory.

Other Design and Analysis Programs:

  • Laminated Plate Theory for stress, strain, and strength calculations. Includes thermal and moisture effects and calculates coefficient of thermal expansions and effective mechanical properties.
  • Horizontal tank design including saddle rings.
  • Hold down lugs per ASME RTP-1.
  • Guy wire analysis for stacks including preload and thermal expansion.
  • ABD matrix calculation for orthotropic materials.
  • Pressure losses in pipe, duct, and fittings due to friction.
  • Ellipse analysis for internal pressure.
  • Torisphere analysis for internal pressure.
  • Stack wind load analysis per BOCA and ASCE codes. Includes vortex shedding effects.
  • Pipe and Duct support spacing per SPI guidelines including the effects of wind, weight, and pressure.
  • Flange analysis per ASME RTP-1 and ASME Section X.
  • Seismic analysis per most building codes.
  • Gusset and bracket analysis.
  • Micromechanics of composites to predict overall material properties based on constituent properties.
  • Finite Element analysis using ANSYS, COSMOSM, and StarDyne (limited versions).

Manufacturing Computer Programs:

  • Filament winding pattern machine sheet generation.
  • Chop / Hoop lay up machine sheet generation.

The programs below demonstrate some of Composites USA's engineering capabilities as related to composite materials. A brief description and partial sample printout of each program follows:

1) COMPOSITE CYLINDER ANALYSIS, RTP-1 CALCULATIONS.

This is Classical Laminated Plate theory adapted to cylinder analysis. Loads can include pressure, axial load, torque, moment, shear, and static head. Material inputs can be any isotropic or orthotropic material. Strain, stress, and strength calculations are performed per ASME RTP-1 guidelines.

2) SIMPLY SUPPORTED RECTANGULAR CORED PLATE WITH UNIFORM PRESSURE.

This program calculates stresses and deformations in rectangular sandwich plates based on Classical Plate Theory. Calculations including core shear deformation are performed using derivations from three separate authors, Dobyns, Plantema, and Allen. A Levy solution, which does not include shear deformation, is also included so that the shear contribution to the deformation can be determined.

3) SIMPLY SUPPORTED CIRCULAR CORED PLATE WITH CENTRAL LOAD, UNIFORM PRESSURE, AND UNIFORM WEIGHT.

This program calculates stresses and deformations in circular sandwich plates. Deflection due to shear deformation in the core is included. The core and face materials are assumed to be isotropic. The three loads (central load, uniform pressure, and uniform weight) produce three individual solutions, which are then superimposed to give total stresses and deformations.

4) BUCKLING OF AN ISOTROPIC CYLINDER WITH LATERAL AND LONGITUDINAL PRESSURE.

This is a comparison of four commonly used buckling calculations for isotropic cylinders. The Roark and Young formulation is exact based on Classical Shell Theory and is a special case of the anisotropic buckling calculations shown in the following program.

5) BUCKLING OF A CYLINDER WITH LATERAL AND LONGITUDINAL PRESSURE OR AXIAL COMPRESSION, NASA SP8007.

This program is exact based on Classical Shell Theory and the lay up can include any sequence of isotropic or orthotropic materials. The lay up is input into a spread sheet program and the ABD matrix (which is the constitutive relationship between the strains and curvatures to the inplane forces and moments) is then pasted into the MathCad program as material property input. If the lay up is isotropic, the solution converges to the solution calculated in Program 4 described above. For the particular case where the laminate is balanced and symmetric but not necessarily isotropic, test data has been obtained on actual buckling loads. This data has been curve fitted to calculate knockdown factors based on actual material properties and geometry. Although the NASA SP8007 test work was performed in the 1960's, it has been verified through additional testing on advanced composite materials in the 1980's.

COMPOSITE CYLINDER ANALYSIS RTP-1 CALCULATIONS
LOADS:
OUTPUT:
PRESSURE (PSI)
10.000
N-Z (LB./IN.)
105.00
AXIAL GTH (in)
0.3728
AXIAL LOAD (LB.)
0.000
N-T (LB./IN.)
210.00
RADIAL GTH (in)
0.0405
MOMENT (IN. LB.)
0.000
N-ZT (LB./IN.)
0.00
PV/W (in.)
2.984E+04
SHEAR (LB.)
0.000
TOT. THICK. (IN.)
0.0500
E-Z (PSI)
1.8705E+06
TORQUE (IN.LB.)
0.000
OUT. RADIUS (IN.)
21.0500
E-THETA (PSI)
2.4669E+06
HEAD(PSI)
0.000
MEAN RAD. (IN.)
21.0250
G-Z,THETA (PSI)
7.6730E+05
MAT1 WT. (LB.)
0.0000
NU-TZ
-0.2607
GEOMETRY:
MAT2 WT. (LB.)
110.5142
NU-ZT
-0.1977
MAT3 WT. (LB.)
0.0000
CTE-T (E-06) deg. F
7.6702
IN. RADIUS (IN.)
21.0000
MAT4 WT. (LB.)
0.0000
CTE-Z (E-06) deg. F
11.5498
L. OF CYL. (IN.)
238.0000
MAT5 WT. (LB.)
0.0000
CTE-TZ(E-06) deg. F
0.0000
TOT. WT. (LB.)
110.5142
END AREA (IN^2)
6.6052
VOL. (IN.^3)
329735.28
I (IN^4)
1459.9181
EI (LB.-IN.^2)
2.7308E+09
EA (LB.)
1.2355E+07
GJ (LB.-IN^2)
2.2404E+09
KAG (LB.)
2.5341E+06

MATERIAL PROPERTY INPUT:

MAT 1
MAT 2
MAT 3
MAT 4
MAT 5
24 oz. Woven
Roving 5/4 weave
NAME
C veil/382
Roving/382
Chop/382
Uni/382
Uni/382
E11 (PSI.)
5.5000E+05
2.4400E+06
1.0300E+06
3.4200E+06
3.4200E+06
E22 (PSI)
5.5000E+05
6.0000E+05
1.0300E+06
8.0000E+05
8.0000E+05
G12 (PSI.)
2.0000E+05
1.4900E+06
3.9000E+05
2.7000E+05
2.7000E+05
NU12
0.3400
0.3378
0.3400
0.3000
0.3000
PLY THICK. (IN.)
0.0130
0.0250
0.0430
0.0147
0.0252
NUMBER OF PLIES
0
2
0
0
0
THICKNESS (IN.)
0.0000
0.0500
0.0000
0.0000
0.0000
ALPHA (DEG.)
0.0000
54.7000
0.0000
0.0000
0.0000
ALPHA (RAD.)
0.0000
0.9547
0.0000
0.0000
0.0000
VOL. FRACT.
0.039
0.400
0.161
0.315
0.315
DENS. (LB./IN.^3)
0.0486
0.0703
0.0544
0.0617
0.0617
NU21
0.3400
0.0831
0.3400
0.0702
0.0702
CTE-1 (E-06)
19.44
3.77
13.20
4.58
4.58
CTE-2 (E-06)
19.44
15.45
13.20
19.72
19.72

COEFFICIENT OF THERMAL EXPANSION CALCULATIONS:

MAT 1
MAT 2
MAT 3
MAT 4
MAT 5
CTE-Z x THICK.
0.0000
0.5775
0.0000
0.0000
0.0000
CTE-T x THICK.
0.0000
0.3835
0.0000
0.0000
0.0000
CTE-TZ x THICK.
0.0000
0.0915
0.0000
0.0000
0.0000

CLT CALC.

MAT 1
MAT 2
MAT 3
MAT 4
MAT 5
COS (ALPHA)
1.0000
0.5779
1.0000
1.0000
1.0000
SIN (ALPHA)
0.0000
0.8161
0.0000
0.0000
0.0000
TAN^2 (ALPHA)
0.0000
Q11
6.219E+05
2.510E+06
1.165E+06
3.494E+06
3.494E+06
Q12
2.114E+05
2.085E+05
3.960E+05
2.452E+05
2.452E+05
Q22
6.219E+05
6.173E+05
1.165E+06
8.172E+05
8.172E+05
Q66
4.000E+05
2.980E+06
7.800E+05
5.400E+05
5.400E+05
QBAR11
6.219E+05
1.972E+06
1.165E+06
3.494E+06
3.494E+06
QBAR12
2.114E+05
-5.142E+05
3.960E+05
2.452E+05
2.452E+05
QBAR16 (+/-)
0.000E+00
7.009E+05
0.000E+00
0.000E+00
0.000E+00
QBAR22
6.219E+05
2.601E+06
1.165E+06
8.172E+05
8.172E+05
QBAR26 (+/-)
0.000E+00
-2.749E+05
0.000E+00
0.000E+00
0.000E+00
QBAR66
2.000E+05
7.673E+05
3.900E+05
2.700E+05
2.700E+05
A MATRIX
9.861E+04
-2.571E+04
0
-2.571E+04
1.300E+05
0
0
0
3.836E+04
DET [A]
4.666E+14
A INVERSE
1.069E-05
2.114E-06
0
2.114E-06
8.107E-06
0
0
0
2.607E-05

STRAINS:

MAT1
MAT2
MAT 3
MAT 4
MAT 5
STRUCT. AXES
EPS -Z
0.0000
0.0016
0.0000
0.0000
0.0000
EPS -T
0.0000
0.0019
0.0000
0.0000
0.0000
EPS -ZT
0.0000
0.0000
0.0000
0.0000
0.0000
MAT. AXES
EPS-1
0.0000
0.0018
0.0000
0.0000
0.0000
EPS-2
0.0000
0.0017
0.0000
0.0000
0.0000
EPS-12
0.0000
0.0002
0.0000
0.0000
0.0000

STRESSES:

MAT1
MAT2
MAT3
MAT4
MAT5
STRUCT. AXES
SIGMA-Z
0.00
2100.00
0.00
0.00
0.00
SIGMA-T
0.00
4200.00
0.00
0.00
0.00
SIGMA-ZT
0.00
568.95
0.00
0.00
0.00
MAT. AXES
SIGMA-1
0.00
4035.42
0.00
0.00
0.00
SIGMA-2
0.00
2264.58
0.00
0.00
0.00
SIGMA-12
0.00
801.40
0.00
0.00
0.00

STRENGTH CALCULATIONS:

MAT1 MAT2 MAT3 MAT4 MAT5
XT (psi)
8250
36600
15450
51300
51300
XC (psi)
6600
29280
12360
41040
41040
YT (psi)
8250
900
15450
1200
1200
YC (psi)
6600
4800
12360
6400
6400
S (psi)
8320
62580
20904
11340
11340
Fxx
1.8365E-08
9.3314E-10
5.2366E-09
4.7498E-10
4.7498E-10
Fxy
-9.1827E-09
-7.3486E-09
-2.6183E-09
-3.9321E-09
-3.9321E-09
Fyy
1.8365E-08
2.3148E-07
5.2366E-09
1.3021E-07
1.3021E-07
Fss
1.4446E-08
2.5535E-10
2.2884E-09
7.7763E-09
7.7763E-09
Fx
-3.0303E-05
-6.8306E-06
-1.6181E-05
-4.8733E-06
-4.8733E-06
Fy
-3.0303E-05
9.0278E-04
-1.6181E-05
6.7708E-04
6.7708E-04
G
0.0000E+00
1.0682E+00
0.0000E+00
0.0000E+00
0.0000E+00
H
0.0000E+00
2.0169E+00
0.0000E+00
0.0000E+00
0.0000E+00
R
0.00
0.41
0.00
0.00
0.00
F
0.41
This is based on the interactive strength theory adopted by RTP-1 1995 which is known as Tsai-Wu in the composites industry. The strengths are calculated based on allowable strain per the recommended equations on page 117. The Design Factor (F) shall be R>10 for the entire laminate and R>1.2 for all other layers for all loading conditions. Materials 1 and 3 are isotropic and 2, 4, and 5 are orthotropic.
Buckling of Isotropic Cylinder with Lateral and Longitudinal Pressure Calculations:

Simply Supported Circular Cored Plate with Central Laod, Uniform Pressure, and Uniform Weight (icludes shear deformation) Calculations:

Composites USA, Inc.
One Peninsula Drive, North East, MD USA 21901
Tel: 1-410-287-2700 Fax: 1-410-287-5222
www.compositesusa.com
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