A square plate (2x2 m) is discretised into two triangular elements. It is assumed that the

Young's modulus E = 1, poisson's ratio v= 0.3 and a plane stress condition is considered with

a thickness t = 1. The chosen elements are either CST (Fig. Q2a) or LST (Fig. Q2b) elements.

The corresponding nodal displacement vectors (d) in a sequence of ABCD are provided below.

d = {d, dg dc dp } = {0 0 -8 -4 -4 0-4 8}

X

B(2,

C(2,2)

B

{0 1 -4 -1 -3 0

u

A(0,0)

'U

(0,2)

H

X

B(2

Figure Q2(a)

d = {d, dg dg de de dy dd, d}" =

-1 2 -3 0.5 2 0.5 4 -1 1 -0.5 1.5 0)

C(2,2)

Figure Q2(b)

A(0,0)

D(0,2)

V

a. Sketch the displacement distributions u and v for both CST and LST elements.

Calculate the stiffness matrices for the CST elements using MATLAB. Provide fully

commented code, explaining the use of each command.

c. Sketch the strains Exx and Eyy on the CST elements. Note that some essential matrix

calculations for strain-displacement are needed.