Effects of Lamina Stacking Sequence and Areal Weight (GSM) on the Mechanical Properties of S‑Glass/Polyester Composites

Authors: Sajid Sadman · Mahfuz Ahmed · Raiyan Hossain
Affiliation: Department of Mechanical & Production Engineering (MPE), Ahsanullah University of Science & Technology (AUST), Dhaka‑1208, Bangladesh
Date: June 2025

📄 Thesis PDF: report/thesis.pdf
🧪 MATLAB code: code/matlab/ → clt_abd.m, run_laminate_final.m
📊 Processed CSVs: data/processed/
🖼️ Figures: figures/

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TL;DR

• Problem: quantify how stacking sequence and areal weight (GSM) affect tensile/flexural behavior of S‑glass/polyester laminates.
• Approach: fabricate laminates at 200 GSM and 600 GSM with two lay‑ups — asymmetric [0/+60/−60] and anti‑symmetric [+60/0/−60]; run ASTM tensile/bending tests and CLT (Classical Lamination Theory) in MATLAB.
• Result (high level): 200 GSM tends to excel in bending, while 600 GSM shows higher tensile capacity; lay‑up choice meaningfully shifts modulus/strength.

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Repository structure

thesis-sglass-polyester-laminate/
├─ report/
│  └─ thesis.pdf
├─ code/
│  └─ matlab/
│     ├─ clt_abd.m              % computes ABD matrices for a stack
│     └─ run_laminate_final.m   % entry point: reproduces CSVs/figures
├─ data/
│  ├─ processed/
│  │  ├─ stress_0-plus60-minus60_asymmetric.csv
│  │  ├─ stress_plus60-0-minus60_antisymmetric.csv
│  │  ├─ strain_0-plus60-minus60_asymmetric.csv
│  │  └─ strain_plus60-0-minus60_antisymmetric.csv
│  └─ (raw/… optional, keep large files private)
├─ figures/
│  ├─ superimposed-strain-components.png
│  ├─ superimposed-stress-components.png
│  ├─ tensile-modulus-200gsm-by-sequence.png
│  ├─ tensile-modulus-600gsm-by-sequence.png
│  ├─ tensile-strength-200gsm-by-sequence.png
│  ├─ tensile-strength-600gsm-by-sequence.png
│  ├─ bending-strength-200gsm-by-sequence.png
│  ├─ bending-strength-600gsm-by-sequence.png
│  ├─ flexural-strength-200gsm-by-sequence.png
│  └─ flexural-modulus-600gsm-by-sequence.png
└─ README.md

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Quick start (MATLAB)

Tested on R2023b; Signal Processing Toolbox recommended.

% In MATLAB, from the repo root:
addpath(genpath('code'));          % or run a startup.m if you add one
run('code/matlab/run_laminate_final.m');

The script will:

• call clt_abd.m to compute A/B/D for each stack,
• reconstruct through‑thickness stress and strain,
• write CSVs into data/processed/ with the names above,
• and save plots into figures/.

If your environment differs, open code/matlab/run_laminate_final.m and edit the material properties, stack definitions, and file paths at the top.

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Data (processed)

Small, publishable CSVs generated by the MATLAB workflow:

• data/processed/stress_0-plus60-minus60_asymmetric.csv
• data/processed/stress_plus60-0-minus60_antisymmetric.csv
• data/processed/strain_0-plus60-minus60_asymmetric.csv
• data/processed/strain_plus60-0-minus60_antisymmetric.csv

Large or confidential raw spreadsheets should remain private; this repo includes only the small processed artifacts needed to reproduce the figures.

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Figure gallery (key results)

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License

• Docs (thesis & figures): CC BY 4.0 (or CC BY‑NC 4.0 if you prefer non‑commercial use only).
• Code: MIT.

Add your chosen licenses as files at the repo root: LICENSE and/or LICENSE-DATA.

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Citation

If you reference this work, please cite:

@thesis{sadman_ahmed_hossain_2025,
  title  = {Effects of Lamina Stacking Sequence and Areal Weight (GSM) on the Mechanical Properties of S‑Glass/Polyester Composites},
  author = {Sajid Sadman and Mahfuz Ahmed and Raiyan Hossain},
  school = {Department of Mechanical and Production Engineering (MPE), Ahsanullah University of Science and Technology (AUST)},
  year   = {2025},
  address= {Dhaka‑1208, Bangladesh}
}

(Optionally add a CITATION.cff file at the repo root so GitHub shows a “Cite this repository” box.)

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Contact

Sajid Sadman · Mahfuz Ahmed · Raiyan Hossain
Department of Mechanical & Production Engineering (MPE), AUST