compression of truss in matlab

To perform compression analysis on a truss in MATLAB, you can use the following steps:

1. Define the nodal coordinates of the truss and connect the nodes with beam elements. You can use the "truss" function in MATLAB to generate a truss structure with specified nodal coordinates.

2. Define the material properties of the beam elements, such as the modulus of elasticity and cross-sectional area.

3. Apply external loads on the nodes of the truss. The external loads can be in the form of point loads or distributed loads.

4. Use the "stiffness" function in MATLAB to obtain the stiffness matrix of the truss.

5. Use the "displacement" function in MATLAB to obtain the nodal displacements of the truss under the applied loads.

6. Use the nodal displacements to calculate the internal forces in each beam element. The internal force can be obtained using the following equation: internal force = modulus of elasticity * cross-sectional area * (change in length / original length).

7. Identify the beam elements that are under compression by checking the sign of the calculated internal force. If the internal force is negative, then the element is under compression.

Below is sample code demonstrating how to perform compression analysis on a truss in MATLAB.

main.m
% Define nodal coordinates of truss
x = [0 1 2 1];
y = [0 0 2 2];

% Connect nodes with beams
truss = [1 2; 1 3; 1 4; 2 3; 2 4];

% Define material properties
E = 200e9; % Modulus of elasticity
A = 0.01; % Cross-sectional area

% Apply external loads
F = zeros(8,1);
F(5) = -1000; % Point load at node 2

% Compute stiffness matrix
K = stiffness(x,y,truss,E,A);

% Compute nodal displacements
U = displacement(K,F);

% Compute internal forces
for i = 1:size(truss,1)
    n1 = truss(i,1); % Node 1
    n2 = truss(i,2); % Node 2
    L = norm([x(n2) - x(n1), y(n2) - y(n1)]); % Length of element
    u1x = U(2*n1-1); % X-displacement at node 1
    u1y = U(2*n1); % Y-displacement at node 1
    u2x = U(2*n2-1); % X-displacement at node 2
    u2y = U(2*n2); % Y-displacement at node 2
    change_in_length = L - sqrt((x(n2) + u2x - x(n1) - u1x)^2 + (y(n2) + u2y - y(n1) - u1y)^2);
    internal_force(i) = E * A * (change_in_length / L);
end

% Identify beams under compression
compression = find(internal_force < 0)
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This code calculates the internal forces in each beam element of a truss structure and identifies the elements that are under compression.