Matrix [A*] is known as the
(A) Pending stiffness matrix.
(B) Transformation matrix.
(C) Coupling stiffness matrix.
(D) Extensional compliance matrix.
The coupling matrix [B] is zero for
(A) symmetric laminates.
(B) all quasi isotropic laminates.
(C) non-symmetric laminates.
A typical graphite epoxy lamina with 70% FVF of 0.005 inch thickness and 1 inch width will fail at about an extensional load applied in direction of fibers
(A) 2000 lbs
(B) 1100 lbs
(C) 3000 lbs
(D) 250 pounds.
The following assumptions relate to the classical lamination theory except
(A) Each lamina is orthotropic.
(B) Each lamina is elastic.
(C) Slip occurs between lamina interfaces.
(D) The lamina is thin
(A) (B) and (D) are called
(A) Coupling, Bending, and Extensional
Stiffness matrices, respectively.
(B) Extensional, Bending, and Coupling
Stiffness matrices, respectively.
(C) Extensional, Coupling, and Bending
Stiffness matrices, respectively.
The [B] matrix for an asymmetric laminate is
(A) zero.
(B) non-zero.
The extensional stiffness matrix [A] for a laminate will not change if
(A) elastic properties of the lamina are
changed.
(B) stacking sequence is changed.
(C) angle of plies is changed.
Under an axial load on a [20/30/30/20] laminate, the global strains vary linearly (choose all that apply).
(A) through the thickness of the laminate
(B) through the thickness of each lamina
For a symmetric [34/65/65/34] Graphite/epoxy laminate, the following is true under a uniaxial load applied in the global x-direction
(A) mid plane strains will be zero
(B) mid plane curvatures will be zero
For a symmetric [34/65/65/34] Graphite/epoxy laminate, the following is true under a twisting load applied on the face perpendicular to the x-axis.xial load applied in the global x-direction
(A) mid-plane curvatures will be zero
(B) mid-plane strains will be zero
Under an axial load on a [20/30/30/20] laminate, the global stresses vary linearly
(A) through the thickness of the laminate
(B) through the thickness of each lamina
In addition to the thickness of the laminate, the in-plane elastic moduli of a symmetric laminate are found by knowing which of the following matrices?
(A) coupling stiffness matrix
(B) bending stiffness matrix
(C) extensional stiffness matrix