Study of Composite Structures Subjected to Underwater Shock Loading

Abstract

Underwater explosions (UNDEX) produce severe and complex loadings in naval applications. Increased use of composite materials in naval applications requires better understanding of how composite structures will respond and survive an UNDEX. A legacy underwater shock loading method, using liquid nitrogen, was implemented to study the dynamic structural response and failure of flat carbon compositeplates. Pressure data was collected using different layouts to study directionality and to characterize the pressure profile of this loading method. A composite test rig was built and utilized to hold composite plates under different backing conditions, water-back (WB) and air-back (AB). Strain response data was collected and analyzed for each composite plate tested. A comparison of water-back and air-back backing conditions was made to better understand the effects of Fluid Structure Interaction in these contrasting backing conditions. Imagery of failure regions was collected, compared, and characterized. Further research is required to validate and more deeply explain the AB and WB comparison results obtained in this research. A compressed air shock pipe underwater release (CASPUR) system was designed and built. Successful initial operational testing of CASPUR was completed. Future pressure profile characterization of CASPUR is needed. Assessment of its efficacy in providing more consistent loading and structure response compared to that of the legacy loading system is required.

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Document Details

Document Type
Technical Report
Publication Date
Dec 01, 2021
Accession Number
AD1164789

Entities

People

  • Caleb H Achor

Organizations

  • Naval Postgraduate School

Tags

Communities of Interest

  • Advanced Electronics
  • Energy and Power Technologies
  • Engineered Resilient Systems
  • Ground and Sea Platforms
  • Sensors
  • Weapons Technologies

DTIC Thesaurus Topics

  • Carbon Fiber Reinforced Polymer
  • Carbon Fibers
  • Composite Materials
  • Composite Structures
  • Data Acquisition
  • Dynamic Response
  • Engineering
  • Environment
  • Explosions
  • Explosives
  • Failure Mode And Effect Analysis
  • Laminates
  • Material Degradation Processes
  • Materials
  • Materials Laboratories
  • Materials Science
  • Materials Testing
  • Measurement
  • Mechanics
  • Pressure Distribution
  • Pressure Measurement
  • Strain Gages
  • United States Naval Academy

Readers

  • Structural Dynamics.
  • Systems Analysis and Design
  • Thermal Physics or Thermal Science.