160 8 Laminate Analysis-Part II >>D=D/3 D= 1.4354 0.0314 -0.0000 0.0314 0.3136 0.0000 -0.0000 0.0000 0.0458 MATLAB Example 8.3 Consider a graphite-reinforced polymer composite laminate with the elastic con- stants as given in Example 2.2.The laminate has total thickness of 0.900 mm and is stacked as a [+30/0]s laminate.The six layers are of equal thickness.Calculate the [A],[B],and [D]matrices for this laminate. Solution This example is solved using MATLAB.First,the reduced stiffness matrix [Q]for a typical layer using the MATLAB function ReducedStiffness as follows: >>Q=ReducedStiffness(155.0,12.10,0.248,4.40) 0= 155.7478 3.0153 0 3.0153 12.1584 0 0 0 4.4000 Next,the transformed reduced stiffness matrix [Q]is calculated for each layer using the MATLAB function Qbar as follows: >Qbar1 =Qbar(Q,30) Qbar1 91.1488 31.7170 95.3179 31.7170 19.3541 29.0342 47.6589 14.5171 61.8034 >Qbar2 =Qbar(Q,-30) Qbar2 91.1488 31.7170-95.3179 31.7170 19.3541 -29.0342 -47.6589 -14.5171 61.8034 >Qbar3 =Qbar(Q,0)160 8 Laminate Analysis – Part II >> D = D/3 D = 1.4354 0.0314 -0.0000 0.0314 0.3136 0.0000 -0.0000 0.0000 0.0458 MATLAB Example 8.3 Consider a graphite-reinforced polymer composite laminate with the elastic con￾stants as given in Example 2.2. The laminate has total thickness of 0.900 mm and is stacked as a [±30/0]S laminate. The six layers are of equal thickness. Calculate the [A], [B], and [D] matrices for this laminate. Solution This example is solved using MATLAB. First, the reduced stiffness matrix [Q] for a typical layer using the MATLAB function ReducedStiffness as follows: >> Q = ReducedStiffness(155.0, 12.10, 0.248, 4.40) Q = 155.7478 3.0153 0 3.0153 12.1584 0 0 0 4.4000 Next, the transformed reduced stiffness matrix ! Q¯" is calculated for each layer using the MATLAB function Qbar as follows: >> Qbar1 = Qbar(Q, 30) Qbar1 = 91.1488 31.7170 95.3179 31.7170 19.3541 29.0342 47.6589 14.5171 61.8034 >> Qbar2 = Qbar(Q, -30) Qbar2 = 91.1488 31.7170 -95.3179 31.7170 19.3541 -29.0342 -47.6589 -14.5171 61.8034 >> Qbar3 = Qbar(Q, 0)