# Parameters configuration import openseespy.opensees as ops # Import OpenSeesPy for structural analysis import opsvis as opsv # Import opsvis for visualization import matplotlib.pyplot as plt # Import Matplotlib for plotting ops.wipe() # Clear any existing model ops.model('basic', '-ndm', 2, '-ndf', 3) # Define a 2D model with 3 degrees of freedom per node (DOF) # Column, girder, and brace dimensions colL, girL, braceL = 4e0, 6e0, 4e0 # Section properties: cross-sectional area (A) and moment of inertia (Iz) Acol, Agir, Abr = 2e-3, 6e-3, 6e-3 IzCol, IzGir, IzBr = 1.6e-5, 5.4e-5, 5.4e-5 # Young's modulus (E) E = 2e11 # Uniform distributed load on the girder (N/m) qGir = 1e4 # Define the material property dictionary for columns and girders Ep = { 1: [2e11, 2e-3, 1.6e-5], # Column elements 2: [2e11, 6e-3, 5.4e-5], # Girder element 3: [2e11, 6e-3, 5.4e-5] # Diagonal elements } # Define the node coordinates ops.node(1, 0, 0) # Bottom left support ops.node(2, 0, 4.0) # Top of the left column ops.node(3, 6.0, 0) # Bottom right support ops.node(4, 6.0, 4.0) # Top of the right column ops.node(5, -4.0, 0) # Ground connection of left diagonal brace ops.node(6, 10.0, 0) # Ground connection of right diagonal brace # Define boundary conditions (supports) ops.fix(1, 1, 1, 1) # Fix all DOFs for node 1 ops.fix(3, 1, 1, 1) # Fix all DOFs for node 3 ops.fix(5, 1, 1, 1) # Fix all DOFs for the bottom left diagonal node ops.fix(6, 1, 1, 1) # Fix all DOFs for the bottom right diagonal node # Plot the model before defining elements opsv.plot_model() # Add title plt.title('plot_model before defining elements') # Define transformation type for elements (Linear) ops.geomTransf('Linear', 1) # Define column and girder elements (elastic beam-column elements) ops.element('elasticBeamColumn', 1, 1, 2, 2e-3, 2e11, 1.6e-5, 1) # Left column ops.element('elasticBeamColumn', 2, 2, 4, 6e-3, 2e11, 5.4e-5, 1) # Girder ops.element('elasticBeamColumn', 3, 4, 3, 2e-3, 2e11, 1.6e-5, 1) # Right column ops.element('elasticBeamColumn', 4, 2, 5, 6e-3, 2e11, 5.4e-5, 1) # Left diagonal brace ops.element('elasticBeamColumn', 5, 4, 6, 6e-3, 2e11, 5.4e-5, 1) # Right diagonal brace # Define external loads Wy = -1e4 # Uniform distributed load in the y-direction Wx = 0 # No horizontal distributed load # Create a dictionary to store element loads Ew = { 2: ['-beamUniform', Wy, Wx] # Distributed load on girder element 2 } # Define time series for constant loads ops.timeSeries('Constant', 1) # Define load pattern using the constant time series ops.pattern('Plain', 1, 1) # Applying point loads # No point loads to apply in this case # Applying distributed loads for etag in Ew: ops.eleLoad('-ele', etag, '-type', Ew[etag][0], Ew[etag][1], Ew[etag][2]) # Analysis settings ops.constraints('Transformation') # Apply transformation constraints ops.numberer('RCM') # Renumber the nodes using Reverse Cuthill-McKee (RCM) ops.system('BandGeneral') # Define the solution algorithm ops.test('NormDispIncr', 1.0e-6, 6, 2) # Convergence test criteria ops.algorithm('Linear') # Use linear algorithm for solving ops.integrator('LoadControl', 1) # Control load increments ops.analysis('Static') # Define a static analysis ops.analyze(1) # Perform the analysis # Print the model data ops.printModel() # Plot the model after defining elements opsv.plot_model() plt.title('plot_model after defining elements') # Plot the applied loads on the model in 2D opsv.plot_loads_2d(nep=10, # Number of points along each element sfac=1, # Scale factor for loads fig_wi_he=(10, 5), # Width and height of the figure fig_lbrt=(0.1, 0.1, 0.9, 0.9), # Left, bottom, right, top margins fmt_model_loads={'color': 'red', 'linewidth': 1.5}, # Formatting for load arrows node_supports=True, # Display node supports truss_node_offset=0.05, # Offset for truss elements ax=None) # Matplotlib axis, None to use current axis # Plot deformations (scaled) after analysis opsv.plot_defo() # Plot internal force diagrams: N (axial), V (shear), M (moment) sfacN, sfacV, sfacM = 5.e-5, 5.e-5, 5.e-5 # Scale factors for internal force diagrams # Plot axial force distribution opsv.section_force_diagram_2d('N', sfacN) plt.title('Axial force distribution') # Plot shear force distribution opsv.section_force_diagram_2d('T', sfacV) plt.title('Shear force distribution') # Plot bending moment distribution opsv.section_force_diagram_2d('M', sfacM) plt.title('Bending moment distribution') # Show all plots plt.show() # Exit the program exit()