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The transverse tensile strength of composites is susceptible to size effects. Therefore, it is paramount to develop length-scale specific physical test procedures to validate computational models that estimate the transverse composite response using micromechanics. To this end, a computational process modeling and virtual mechanical testing framework are presented in this study to predict the transverse response of composite microstructures subjected to processing conditions. Informed by a comprehensive material dataset, the numerical model is shown to reliably predict the process-induced residual stress generation in composite microstructures and accurately evaluate its influence on their transverse strength prediction. A novel procedure to fabricate thin composite laminates from a single ply of carbon fibers and characterize their transverse tensile response is presented to validate the numerical model. The results show excellent agreement with the virtual test predictions. This study highlights the importance of length-scale specific testing to minimize the influence of size effect on the transverse composite strength.
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Structural responses of FRP sheet piles under cantilever loading
Sheet piles are interlocked segments used for temporary or permanent soil and water retaining structures such as below-grade parking structures and sea walls. Although steel is commonly used due to its strength and ease of manufacturing, it rusts in saltwater. Fiber reinforced polymer (FRP) composite sheet piles are resistant to chlorides and have higher corrosion resistance, but their mechanical properties vary in length and width. Stress risers at corrugation corners make soil-structure interaction a challenging design issue. This research aims to develop a standardized test procedure to determine the resisting moment capacity of FRP composite sheet piles. Cantilevered FRP sheet piles fixed with a sand-concrete mixture of ~70 psi (0.48 MPa) compressive strength were tested under static loads. Strain gages and LVDTs were used to collect data on deformation response up to and beyond peak induced stress. Results suggest that the refined test procedure can assist engineers in designing efficient sheet pile structures and become a basis to develop ASTM standard.
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- Award ID(s):
- 1916677
- PAR ID:
- 10476966
- Publisher / Repository:
- Sustainable Development Press
- Date Published:
- Journal Name:
- Sustainable Structures
- Volume:
- 3
- Issue:
- 1
- ISSN:
- 2789-3111
- Subject(s) / Keyword(s):
- Fiber reinforced polymer composites piling sheet pile testing structural response cantilever loading
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.54113/j.sust.2023.000021
