Effects of ply angle and blocking on open-hole tensile strength of composite laminates: A design and certification perspective

T. R.C. Chuaqui, M. W.D. Nielsen, J. Colton, R. Butler, A. T. Rhead

Research output: Contribution to journalArticlepeer-review


The failure strength of carbon-fibre reinforced plastic laminates under open-hole tension varies considerably with ply angle, ply blocking and loading direction. Here, laminates with various standard-angle and non-standard angle stacking sequences are subjected to both on- and off-axis loading in a comprehensive experimental and progressive damage finite element analysis testing campaign. It is found that interlaminar and intralaminar matrix damage can be beneficial when accumulated sub-critically in ply blocks aligned with loading direction, but can also lead to significant strength decreases owing to edge failure. In such cases, a numerical edge treatment is proposed for more accurate representation of open-hole tensile strength in large structures where holes are positioned away from free edges. The solution suppresses edge failure and results in up to 80% strength increases, challenging the validity of standard open-hole tension testing and current design rules for some applications.

Original languageEnglish
Article number108582
JournalComposites Part B: Engineering
Early online date28 Dec 2020
Publication statusPublished - 15 Feb 2021


  • A. Carbon fibre
  • B. Strength
  • B. Stress concentrations
  • C. Finite element analysis (FEA)

ASJC Scopus subject areas

  • Ceramics and Composites
  • Mechanics of Materials
  • Mechanical Engineering
  • Industrial and Manufacturing Engineering

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