Performance of Structural Blast Mitigation Measure for Oil and Gas Industrial Facilities

The response of the bulkhead type of blast wall under deflagration blast pulse was studied using finite element modelling software. The behavior of unstiffened and stiffened panels was analyzed. The study aimed at determining the effect of plate and stiffener thicknesses on energy dissipation and distribution of reaction forces. This was carried out in order to optimize the response of the primary steelwork through typological and geometrical modifications of the local element. Furthermore, novel strategies for the improvement of the blast response were introduced with a focus to use alternative materials and innovative connections. The latter was assessed numerically using a simplified model and its benefits were analyzed by comparing with the traditional approach.

On firework blasts and qualitative parameter dependency

In this paper, a mathematical model is developed to qualitatively simulate the progressive time-evolution of a blast from a simple firework. Estimates are made for the blast radius that one can expect for a given amount of detonation energy and pyrotechnic display material. The model balances the released energy from the initial blast pulse with the subsequent kinetic energy and then computes the trajectory of the material under the influence of the drag from the surrounding air, gravity and possible buoyancy. Under certain simplifying assumptions, the model can be solved for analytically. The solution serves as a guide to identifying key parameters that control the evolving blast envelope. Three-dimensional examples are given.

Impact and Blast Pulse: Improving Energy Absorption of Fibre-Reinforced Composites Through Optimized Tailoring

This paper tries to conjugate an improvement of stiffness and delamination damage resistance. A number of published results allow us to guess the existence of fibre orientations that are a good compromise for an optimal absorption of the incoming energy and for maintaining of a high stiffness. Optimal absorption is herein intended as a way not involving weak properties, such as interlaminar strength. We seek for an optimal orientation of reinforcement fibres through definition of stationary conditions for bending and shear energy contributions under in-plane variation of plate stiffness coefficients. Our goal is to tune the energy absorption as desired. Two kinds of optimized layers are studied, that are compatible with current production technologies: type 1 reduces bending without substantially increasing the transverse shear stresses, type 2 reduces transverse shear stresses without substantially increasing deflections. Incorporation into the laminates of couples of these layers with opposite features and the same mean properties of those they substitute allows an energy transfer from an unwanted to a wanted mode, as shown by the numerical applications. In this way, the deflections and the stresses inducing delamination damage of laminates subjected to impact and blast pulse loads were reduced, while damping should not substantially change since the variation of the orientation of fibres lies in a range where mild variations of it are induced.