SUBJECT: Ph.D. Proposal Presentation
BY: Siddharth Avachat
TIME: Friday, June 27, 2014, 10:00 a.m.
PLACE: MRDC Building, 4211
TITLE: Design of Composite Structures for Underwater Blast Mitigation
COMMITTEE: Dr. Min Zhou, Chair (ME)
Dr. Nazanin Bassiri-Gharb (ME)
Dr. George Kardomateas (AE)
Dr. Julian Rimoli (AE)
Dr. Shuman Xia (ME)


Structural design of ships and submersibles is a complex undertaking, because the deformations experienced by naval vessels are a result of the combined effects of multiple loads acting simultaneously. The analysis of the blast response of marine composite structures is further complicated by material heterogeneities, geometric nonlinearities and multi-axial loading conditions which cause unpredictable failure. Effective design of marine composite structures requires an intimate understanding of dynamic deformation and failure and a capability to predict and control their performance. The complexity of technical issues necessitates detailed experiments that account for realistic service environments and a complementary computational framework that allows a wide range of scenarios to be explored. The input from such parametric technical approaches can be utilized to address the need for better designed, more durable, blast resistant and lightweight marine vessels.

The proposed research aims to address this need and provide quantitative guidance for structural design of navy ships. To this end, a novel test environment is constructed to specifically provide controlled underwater impulsive loading and measure time- and space-resolved deformation and failure in composite structures. These measurements allow the characterization of failure modes and collapse behavior of composite structures in ways that have not been possible until now. Concurrent finite-element simulations are carried out to accurately track the different damage modes and evaluate the energy dissipation and impulse resistance characteristics of different materials and structures. This combined experimental and numerical approach enables exhaustive exploration of design scenarios involving simultaneous variations in loading conditions, material properties and geometric attributes to develop quantitative loading-structure-performance relationships. The proposed research is expected to yield data and criteria for the design of blast resistant composite structures and vessels for next generation naval applications.