A. Schiffer

Graphene Foam Developed with a Novel Two-Step Technique for Low and High Strains and Pressure-Sensing Applications

Freestanding, mechanically stable, and highly electrically conductive graphene foam (GF) is formed with a two-step facile, adaptable, and scalable technique. This work also demonstrates the formation of graphene foam with tunable densities and its use as strain/pressure sensor for both high and low strains and pressures.

The response of rigid plates to blast in deep water: fluid–structure interaction experiments

Laboratory-scale dynamic experiments are performed in order to explore the one-dimensional response of unsupported rigid plates to loading by exponentially decaying planar shock waves in deep water. Experiments are conducted in a transparent shock tube allowing measurements of plate motion and imparted impulse, as well as observation of cavitation in water, including motion of breaking fronts and closing fronts. Loading of both air-backed and water-backed rigid plates is examined, and the sensitivity of plate motion and imparted impulse to the structural mass and to the initial hydrostatic pressure in the water is measured. Experiments also serve to validate recently developed theoretical models, whose predictions are found to be in agreement with measurements.

The Response of Rigid Plates to Deep Water Blast: Analytical Models and Finite Element Predictions

One-dimensional analytical models and finite element calculations are employed to predict the response of a rigid plate, supported by a linear spring, to loading by a planar pressure shock wave traveling in water or in a similar inviscid liquid. Two problems are considered: (i) a spring-supported rigid plate in contact with fluid on one side and (ii) a spring-supported rigid plate in contact with fluid on both sides; for both problems, plates are loaded by an exponentially decaying shock wave from one side. Cavitation phenomena in the liquid, as well as the effect of the initial static fluid pressure, are explicitly included in the analytical models and their predictions are found to be in excellent agreement with those from FE calculations. The validated analytical models are used to determine the sensitivity of the plate’s response to mass, spring stiffness and initial static pressure. [DOI: 10.1115/1.4006458]

The response to underwater blast

Polymer composites can display a response to blast events superior to that of metallic constructions. To achieve optimal designs of blast-resistant composite structures for underwater applications, it is necessary to understand the complex fluid–structure interaction and to develop predictive models. In this chapter we review the lessons learnt from extensive observation of underwater events at laboratory scale and their use in design. We describe the details of an experimental technique allowing simultaneous observation of structural motion and fluid response in underwater blast events. Then, we summarise our experimental findings on the underwater blast response of several types of structures. We outline a modelling strategy and its application to the construction of design maps.