Strength¶
- class composipy.strength_class.Strength(laminate, load)[source]¶
This class creates the Strength object. It’s inputs are Laminate and Load objects. The strength Object returns laminate strenght parameteres, including strain and stress in laminate and load coordinates. It also returns the Tsai-Wu failure index for all plies in the current load conditions and the First Ply Failure analysis (based on Tsai-Wu failure criterion).
- Parameters
laminate (Laminate) – The laminate is an object that contains the layup scheme with its mechanical proprieties. [(angle_of_ply_1, ply_1), (angle_of_ply_2, ply_2), … (angle_of_ply_n, ply_n)]
load (Load) – Load is and object that contains the in-plane forces and moments in x and y directions. Load(Nx, Ny, Nxy, Mx, My, Mxy)
Example
>>> from composipy import Ply, Laminate, Load, Strength >>> ply_1 = Ply(129500, 9370, 0.38, 5240, 0.2) >>> layup_1 = [(90, ply_1), (0, ply_1), (90, ply_1)] >>> laminate_1 = Laminate(layup_1) >>> load_1 = Load(100, 200, 50, 1000, 250, 100) >>> str_analysis = Strength(laminate_1, load_1) >>> str_analysis.mid_strain_xy # Returns the mid-plane strain and slope of the laminate in xy coordinates >>> str_analysis.mid_strain_12 # Returns the mid-plane strain and slope of the laminate in 12 coordinates >>> str_analysis.stress_xy # Returns the maximum stress for all plies in the xy coordinates >>> str_analysis.stress_12 # Returns the maximum stress for all plies in the 12 coordinates >>> str_analysis.TW_i # Returns the Tsai-Wu failure index for all plies >>> str_anaysis.FPF # Prints the First Ply Failure load, failed plies, TW_i for the laminate and Strength Ratio
References
1 - JONES, M. Robert. Mechanics of Composite Materials. Taylor & Francis: 2nd ed 1999. 2 - Analysis and Design of composite structures. Class notes. ITA 2020.
- property mid_strain_xy¶
[strain_x, strain_y, strain_xy, slope_x, slope_y, slope_xy]
- property mid_strain_12¶
[strain_1, strain_2, strain_12, slope_1, slope_2, slope_12]
- property stress_xy¶
[sigma_x, sigma_y, tau_xy] for each ply
- property stress_12¶
[sigma_1, sigma_2, tau_12] for each ply
- property TW_i¶
Tsai-Wu index (F12 was aproximated using Hoffman criterion)
- property FPF¶
First Ply Failure analysis