1. STRESS ANALYSIS OF BASALT /EPOXY LAMINATE
J.Alexander1, DR.BSM.Augustine2
1
,PhD Scholar, Sathyabama University,Chennai-600119 e-mail
vsjalexander@rediffmail.com
2
Professor,Sathyabama University,Chennai-600119
Introduction
BASALT FIBER, A new kind of inorganic fiber like glass fiber, is
fabricated from basalt rocks through the melting process. It has a
higher working temperature and better tensile strength than E-glass
fiber as well as good resistance to chemical attack, impact load, and
fire with less poisonous fumes. In addition, the basalt fibers do not
need any other additives in the single producing process, adding
special benefit in cost. Basalt fiber reinforced composites show great
improvement in the elastic modulus, chemical resistance and thermal
stability compared to glass fiber reinforced composites. These
advantages make basalt fiber a promising alternative to glass fiber as
a reinforcement material in aerospace, metallurgical, chemical,
building industries and so on. In the past five years the use of basalt
fibers have been tried in many applications and close attention has
been paid to its qualities, especially the excellent chemical resistance
which accelerates the application of basalt fibers in both organic and
inorganic matrix composites. At this work Basalt epoxy laminate was
fabricated using hand lay up process and the material properties were
found using experimental methods. Classical Laminated theory is
used for calculating Lamina stresses which are compared with lamina
stresses of various composite materials.The result shows baslt/epoxy
laminate has very good strengths at axial loads.

2. The basalt fiber used in the experiment was Basalt fabric whose
density is2.7grams/cm3 mixed with LY552 epoxy resins .The fiber –
resin volume fraction is 60:40 After being impregnated in resins and
cured, the basalt yarns were cut short to about 350 mm, and smooth
and rounded specimens were selected for the tests of tensile strength,
tensile modulus and elongation at break. Both ends of the selected
samples were tabbed by two pieces of starched paper to avoid the end
breakage caused by test machine clamp. The gauge length of the
sample was 200 mm. The basalt yarns tensile strength was tested on a
universal testing machine according to GB3362-82, and the load
velocity was 2 mm/min.
Table i Tensile Test Results
Width(mm Thickness(mm) Breaking Tensile Tensile
) load(N) strength modulus
(N/mm^2) (KN/mm^2)
26.4 4.3 16.8 148 12.247
25.8 4.65 15.38 128 11.822
24.8 4.8 17.1 144 10.952
Table ii Compression test Results
Area (mm^2) Breaking load(N) Compression strength
(N/mm^2)
12.25*12.65 30.96 200
13.5*13.75 24.8 134
13.5*13.25 29.06 163
The above Test result are used in the laminated plate theory for stress
analysis
II Laminated Plate Theory
The mechanics of materials deal with stresses, strains, and
deformations in engineering structures subjected to mechanical and
thermal loads. A common assumption in the mechanics of
conventional materials, such as steel and aluminum, is that they are

3. homogeneous and isotropic continua. For a homogeneous material,
properties do not depend on the location, and for an isotropic
material, properties do not depend on the orientation. Unless severely
cold-worked, grains in metallic materials are randomly oriented so
that, on a statistical basis, the assumption of isotropy can be justified.
Fiber-reinforced composites, on the other hand, are microscopically
inhomogeneous and non isotropic (orthotropic). As a result, the
mechanics of fiber-reinforced composites. Lamination theory is
useful in calculating stresses and strains in each lamina of a thin
laminated structure. Beginning with the stiffness matrix of each
lamina, the step- by-step procedure in lamination theory includes
1. Calculation of stiffness matrices for the laminate
2. Calculation of mid plane strains and curvatures for the laminate
due to a given set of applied forces and moment s
3. Calculation of in-plane strains εxx, εyy , and γxy for each lamina
4. Calculation of in-plane stresses sxx, syy , and txy in each lamina
The geometric midplane of the laminate contains the xy axes, and the z axis
defines the thickness direction. The total thickness of the laminate is h, and
the thickness of various laminas are represented by t1, t2, t3, and so on. The
total number of laminas is N. A sketch for the laminate is shown in
Figure 1

4. ----------------------------------------------------
-----------------------------------------------------------(1)
where
ε0xx -, ε0yy mid plane normal strains in the laminate
0
γ xy - mid plane shear strain in the laminate
kxx ,- k yy bending curvatures of the laminate
kxy - twisting curvature of the laminate
z - distance from the mid plane in the thickness direction
Laminate Forces and Moments

5. Applied force an d moment resultant (Figure 2) on a laminate are
related to the mid plane strains and curvatures by the following
equations
-----------------------------------(2)
FIGURE 2 In-plane, bending, and
twisting loads applied on a laminate.
In matrix notion the force and moment equations are written as
--------------------------
-----------------------------------------------(3)
------------------------------
-----------------------------------------------(4)

6. ----------------------------------------
-------------------------------------------------(5)
------------------------------------------------------------------------------------------
(6)
--------------------------------------------------------------------------------------------
(7)
The fabricated Basalt/epoxy laminate is subjected to an axial load of
100N in the X direction and the stresses in each ply is analysed by
using matlab software .
*************************************************************
****
* Analysis of Composite Laminates Based on
*
* Classical Laminated Plate Theory *
*******************************************************
***********************
Material 4: User Material: BASALT/EPOXY552
Engineering Properties
**********************
Matl E1 E2 G12 v12
1 1.810e+011 1.028e+010 7.172e+009 0.280
2 3.931e+010 8.552e+009 3.724e+009 0.280
3 8.690e+010 5.517e+009 2.138e+009 0.340
4 5.480e+010 1.757e+010 7.138e+009 0.232
Stacking Sequence
*****************
Layer Matl Ply Angle Ply Thickness
1 4 30.0 1.200e+000
2 4 60.0 1.200e+000

7. 3 4 30.0 1.200e+000
----------
Laminate Mechanical Input Load Vector
*************************************
NX NY NXY MX MY
MXY
1.000e+002 0.000e+000 0.000e+000 0.000e+000 0.000e+000
0.000e+000
Laminate Matrices
*****************
'ABD' Matrix
1.191e+011 3.977e+010 3.431e+010 7.629e-006 5.722e-006
3.815e-006
3.977e+010 9.636e+010 2.475e+010 5.722e-006 1.144e-005
2.861e-006
3.431e+010 2.475e+010 5.053e+010 3.815e-006 2.861e-006
7.629e-006
7.629e-006 5.722e-006 3.815e-006 1.504e+011 4.295e+010
4.623e+010
5.722e-006 1.144e-005 2.861e-006 4.295e+010 8.224e+010
1.755e+010
3.815e-006 2.861e-006 7.629e-006 4.623e+010 1.755e+010
5.458e+010
Apparent Laminate Stiffness Properties
**************************************
EX EY GXY EXB
EYB
2.487e+010 2.187e+010 1.070e+010 2.597e+010 1.788e+010
Apparent Laminate Coupling Coefficients
(Poisson and Shear Coupling)
***************************************
vXY vYX nXY,X nXY,Y nX,XY nY,XY
0.273 0.240 -0.545 -0.327 -0.235 -0.
Laminate Total Strain Vector
****************************
eX eY gXY KX KY KXY
1.117e-009 -3.046e-010 -6.091e-010 -4.898e-026 -2.501e-027
6.534e-026
Stresses and Strains in the Global Coordinate System (X,Y) - Lower
Surfaces
*******************************************************
*********************
Layer Eps-X Eps-Y Gam-XY Sig-X Sig-Y
Sig-XY
1 1.117e-009 -3.046e-010 -6.091e-010 3.321e+001 3.540e+000
3.775e+000
2 1.117e-009 -3.046e-010 -6.091e-010 1.691e+001 -7.081e+000
-7.549e+000
3 1.117e-009 -3.046e-010 -6.091e-010 3.321e+001 3.540e+000
3.775e+000
Stresses and Strains in the Material Coordinate System (1,2) - Lower
Surfaces
Strains are given as Total Strains (Mechanical + Thermal +
Moisture)

8. *******************************************************
**********************
Layer Eps-1 Eps-2 Gam-12 Sig-1 Sig-2
Sig-12
1 4.978e-010 3.146e-010 -1.536e-009 2.906e+001 7.689e+000
-1.096e+001
2 -2.129e-010 1.025e-009 -9.265e-010 -7.621e+000 1.745e+001
-6.613e+000
3 4.978e-010 3.146e-010 -1.536e-009 2.906e+001 7.689e+000
-1.096e+001
Material Strengths
******************
Matl Xt Xc Yt Yc S
1 1.500e+009 -1.500e+009 4.000e+007 -2.462e+008
6.828e+007
2 1.083e+009 -6.207e+008 3.931e+007 -1.283e+008
8.897e+007
3 1.276e+009 -3.379e+008 2.897e+007 -1.579e+008
4.897e+007
4 1.480e+008 -2.000e+008 1.480e+008 -2.000e+008
1.400e+007
Conclusion
For a particular load the stresses in each layer is calculated .These stress
values are compared with results of same type of laminate with different
material. But the properties of basalt /epoxy laminate is better than
Glass/epoxy laminate. Hence glass/epoxy can be replaced by Basalt/epoxy
for various structural applications. (Detailed results will be discussed in the
full paper.
References
1. Medvedyev, O. O. and Tsybulya, Y. L. (2004). The Outlook for the use of
Basalt Continuous Fibers for Composite Reinforcement[C], International
SAMPE Technical Conference, SAMPE 2004, 16–20 May 2004, Long
Beach, CA, United States, pp. 275–279.
The effect of adhesion interaction on the mechanical properties of
2.
thermoplastic basalt plastics P. I. Bashtannik, A. I. Kabak,and Yu.
Yakovchuk, Mechanics of Composite Materials, Vol. 39, No. 1, 2003.
3 Novel basalt fibre reinforced glass matrix composites, e. bernardo e. stoll†,,
a. r. boccaccini j mater sci 41 (2006) 1207–1211.
4. Chemical Composition and Mechanical Properties of Basalt and Glass Fibers:
A Comparison Tamás Deák and Tibor Czigány,Textile Research Journal 2009 79: 645.

9. .