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Updated: Aug 10, 2025
06:34
Finite Element Modeling for the Simulation of the Quasi-Static Compression of Corrugated Tapered Tubes
Published on: January 6, 2023
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Increasing reliability of axially compressed cylinders through stiffness tailoring and optimization
R L Lincoln1, P M Weaver1, A Pirrera1
1Bristol Composites Institute, University of Bristol, BS8 1TR Bristol, UK.
Summary
The rapid tow shearing (RTS) process enhances cylindrical shell design by reducing imperfection sensitivity. This fibre-steering technique improves reliability and stiffness, outperforming traditional methods for axially compressed shells.
Area of Science:
- Composite Materials Engineering
- Structural Mechanics
- Aerospace Engineering
Background:
- Axially compressed cylindrical shells exhibit significant imperfection sensitivity, limiting their structural performance.
- Traditional composite manufacturing methods often struggle to optimize shell structures for both strength and stiffness.
- The rapid tow shearing (RTS) process offers a novel approach for manufacturing complex composite structures with tailored properties.
Purpose of the Study:
- To investigate the efficacy of the rapid tow shearing (RTS) process in mitigating the imperfection sensitivity of axially compressed cylindrical shells.
- To optimize the design of RTS-manufactured shells using a genetic algorithm considering manufacturing imperfections and axial stiffness.
- To compare the reliability and performance of RTS-enabled shells against traditional straight fibre (SF) and quasi-isotropic laminate designs.
Main Methods:
- The RTS process was employed to deposit curvilinear carbon fibre tapes, creating embedded rings and stringers with fibre-angle-thickness coupling.
- A genetic algorithm was utilized to maximize the 99.9% reliability load, incorporating realistic manufacturing imperfections and an axial stiffness penalty.
- The first-order second-moment method was applied to estimate the 99.9% reliability load, with buckling data normalized by mass and thickness.
Main Results:
- Optimized SF and RTS laminates demonstrated a 6% and 8% higher 99.9% normalized reliability load, respectively, compared to a quasi-isotropic laminate.
- Relaxing the axial stiffness penalty further increased performance, with RTS cylinders exceeding the quasi-isotropic laminate by 37%.
- Improvements were primarily attributed to a significant reduction in the variance of the buckling-load distribution, highlighting reduced imperfection sensitivity.
Conclusions:
- The RTS process is highly effective in reducing the imperfection sensitivity of axially compressed cylindrical shells.
- Fibre-steered composite structures manufactured via RTS offer substantial improvements in reliability and performance compared to conventional designs.
- This study demonstrates the potential of RTS for creating lighter, stiffer, and more reliable shell structures through advanced material tailoring.
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