Improved Methodology for Accurate Prediction of Blast Wave Clearing on a Finite Target
Publication: Journal of Engineering Mechanics
Volume 148, Issue 9
Abstract
Accurate estimation of blast loads on a structure requires consideration of several complex phenomena during interaction with the target surface. One such phenomenon is the clearing effect observed during the diffraction of blast waves from finite reflecting targets. A clearing wave is generated due to the pressure difference between the edge and internal locations of the target surface, which reduces the reflected impulse at the considered location on the target surface. The state of the practice relies on simplified empirical methods to predict the clearing effects, which are often inaccurate or may also be unconservative. Past analytical studies on the clearing effect have mainly focused on weak blast, where the clearing wave speed is assumed to be the ambient sound speed. In the present study, the authors propose a methodology to include the effect of clearing on reflected overpressure history for strong blasts by considering an average clearing wave speed computed using the ideal gas law. The modified approach was verified and validated with existing literature and benchmarked against numerical studies. The proposed clearing methodology was shown to address the limitations of the current state of practice. Finally, a simplified version of the proposed clearing model was presented in the form of charts that can be used to compute the reflected overpressure history, including the effect of clearing on a finite-surface rectangular target.
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Data Availability Statement
All of the data, models, and code generated or used during the study are present in the published article.
Acknowledgments
The financial support for this research work was provided through a Core Research Grant award by the Science and Engineering Research Board of the Department of Science and Technology, Government of India. The authors gratefully acknowledge the support.
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Information & Authors
Information
Published In
Journal of Engineering Mechanics
Volume 148 • Issue 9 • September 2022
Copyright
© 2022 American Society of Civil Engineers.
History
Received: Feb 2, 2022
Accepted: Apr 19, 2022
Published online: Jul 4, 2022
Published in print: Sep 1, 2022
Discussion open until: Dec 4, 2022
ASCE Technical Topics:
- Analysis (by type)
- Blasting effects
- Computer models
- Continuum mechanics
- Design (by type)
- Dynamics (solid mechanics)
- Engineering fundamentals
- Engineering mechanics
- Fluid mechanics
- History
- History and Heritage
- Hydrologic engineering
- Load factors
- Models (by type)
- Numerical analysis
- Practice and Profession
- Solid mechanics
- Structural design
- Structural dynamics
- Surface waves
- Water and water resources
- Wave diffraction
- Wave reflection
- Waves (fluid mechanics)
- Waves (mechanics)
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