This study investigates the mechanical and geometrical attributes of egg–box energy absorbing structures as crash safety barriers in the automotive industry. The research herein was originated from the earlier work of Prof. Shirvani, patented and further investigated by Cellbond Composites Ltd. who has invested in further research, for developing an analytical tool for geometric optimisation as an enhanced resolution to various shapes and materials. Energy absorption in egg-box occurs through plastic deformation of cell walls, examined through non–linear finite element simulations using ANSYS® and ANSYS/LS–DYNA® FE packages. Experimental dynamic crash tests have been designed to verify the validity of the FE simulations. Geometrical models are defined as 3D graphical representations, outlined in detail. Further, the impact behaviour of commercially pure aluminium egg-box energy absorbers is studied to identify the optimum design parameters describing the geometry of the structure. A simulation-based multi-objective optimisation strategy is employed to find a set of Pareto-optimal solutions where each solution represents a trade-off point with respect to the two conflicting objectives: the maximum impact force and the energy absorption capacity of the structure. The aim is to simultaneously minimise the former and maximise the latter, in the attempt to find purpose–specific optimal egg–box geometries. In light of the associated outcomes, it is shown that egg–box geometries with < ω ), thin walls (t < 1mm), short inter–peak distances and small peak diameters. M – < ω ), thin walls (t < 1mm), lengthy inter–peak distances and smaller peak diameters. It is concluded that, egg–box structures combined in the form of sandwich panels can be designed per application to act as optimised energy absorbers. Results of the proposed optimised sandwich structure are verified using analytical techniques.

The dissertation present an approach to decreasing the risk of transportation of hazardous materials by applying construction related solution. They consist in deploying safety barriers between transportation routes and vulnerable property built in the roadside territory. The attention is focussed on the hazmat transportation accidents known as boiling liquid expanding vapour explosion (BLEVEs). It is considered how to predict thermal and mechanical effects of BLEVEs on potential barriers or roadside property. It is suggested to interlink results of this prediction with the conventional structural response techniques used for estimating the susceptibility of safety barriers to the effects of BLEVEs. / Disertacijoje pateikiamas originalus būdas mažinti pavojingųjų medžiagų vežimo riziką taikant statybinio pobūdžio priemones. Tos priemonės - saugos barjerai,kurie yra statomi tarp transporto linijų ir pažeidžiamų pakelės objektų. Didžiausias dėmesys, telkiamas į transporto avarijas, kurios vadinamos besiplečiančių verdančių skysčio garų sprogimas (BLEVE). Nagrinėjama, kaip prognozuoti šiluminius ir mechaninius tokių sprogimų poveikius. Jie gali pažeisti pakelėse esančius statinius. Juos turi sumažinti saugos barjerai. BLEVE poveikių prognozavimą siūloma susieti su konstrukcijų skaičiavimo metodais, kuriais vertinama barjerų reakcija į šiuos poveikius.

Dans ce travail, nous expliquons l'application de la méthodologie MADS/MOSAR sur le secteur de extraction minier colombien et nous analysons le lien existant entre la législation colombienne et trois scénarios d'accident (explosion, effondrement post-opération et les maladies pulmonaires). L'ensemble réglementaire d’un pays peut être appréhendé comme des barrières de sécurité et joue un rôle important dans la gestion de la sécurité. La définition, la classification et l'exécution des barrières réglementaires, permet à l’administrateur des risques technologiques d'effectuer une réduction du risque afin d'augmenter l'acceptabilité dans le contexte régional. Il permet d'identifier les flux de dangers pour un groupe d'événements, de définir l'existence ou l’absence de barrières réglementaires et de produire un panorama global positionnant les différents instruments existants et autorisant de futures opportunités de gestion. Les résultats de notre analyse montrent un point de vue qui peut être très utile pour qu'un gouvernement local ou un système national développe et/ou évalue son propre ensemble réglementaire pour la gestion des risques / N this work, we explain the application of the MADS/MOSAR methodology in the Colombian mining sector and analyze the current legislation linked with three scenarios (explosion, post-operation collapsing and pulmonary diseases). The entire normative body of a country can be conceived as safety barriers and it plays an important role in industrial safety management. The definition, classification and performance of the normative barriers, allows the management of technological risks to perform a risk reduction in order to enhance the acceptability in the regional context. It permits to identify the flux of danger for a group of events, to define the existence of normative barriers and to generate a global panorama over the position of the different instruments that already exist allowing future management opportunities. The results of our analysis show a point of view that can be very useful for a local government or a whole national system to develop and/or evaluate his legislative instruments of risk management

One of the challenges for Airbus preparing a new freighter development process was the design of a solid freighter barrier, which separates the courier area from the cargo compartment. The major task of such a barrier is to protect the passengers against all risks caused due to cargo impact by a justifiable design. These risks may result from all kind of survivable incident and accident scenarios. Real aircraft crashes were analyzed to get away from a static book-case and come to a more realistic dynamic crash scenario. A reduced-order simulation model was built up to investigate and simulate the dynamic effects during crash. The simulation model considers the highly nonlinear stiffness and damping characteristics of all critical cargo types and also includes their energy absorption potentials. A series of full scale container crash tests have been performed at accredited car crash facilities. The test campaigns were complemented by numerous component tests to study also general crash principles. The critical simulation parameters were identified and implemented into the simulation model. The subsequent validation process showed a close agreement between simulation and test. The simulation environment has turned out to be a reliable basis to simulate all critical barrier loads with respect to the specific aircraft loading distributions. The essence of this investigation is an adequate understanding of the real crash effects. The proposed dynamic crash approach is more realistic than the static condition and results in an optimized safety barrier wall concept. This dynamic approach provides equivalent safety compared to the existing devices and is accepted by FAA and EASA.

One of the challenges for Airbus preparing a new freighter development process was the design of a solid freighter barrier, which separates the courier area from the cargo compartment. The major task of such a barrier is to protect the passengers against all risks caused due to cargo impact by a justifiable design. These risks may result from all kind of survivable incident and accident scenarios. Real aircraft crashes were analyzed to get away from a static book-case and come to a more realistic dynamic crash scenario. A reduced-order simulation model was built up to investigate and simulate the dynamic effects during crash. The simulation model considers the highly nonlinear stiffness and damping characteristics of all critical cargo types and also includes their energy absorption potentials. A series of full scale container crash tests have been performed at accredited car crash facilities. The test campaigns were complemented by numerous component tests to study also general crash principles. The critical simulation parameters were identified and implemented into the simulation model. The subsequent validation process showed a close agreement between simulation and test. The simulation environment has turned out to be a reliable basis to simulate all critical barrier loads with respect to the specific aircraft loading distributions. The essence of this investigation is an adequate understanding of the real crash effects. The proposed dynamic crash approach is more realistic than the static condition and results in an optimized safety barrier wall concept. This dynamic approach provides equivalent safety compared to the existing devices and is accepted by FAA and EASA.:Contents 1 Scope of the Work 1 1.1 State-of-the-Art Barrier Design 1 1.2 General Crash Justification Requirement 2 1.3 Barrier Protection Criterion 3 1.4 Proposed Dynamic Approach for an Optimized Safety Barrier Design 4 2 Simulation 6 2.1 About this Chapter 6 2.2 Simulation environment Matlab/Simulink 7 2.3 Simulation Model 7 2.4 Differential Equation 11 2.5 Stiffness and Damping 14 2.6 Crash Pulses 17 2.7 Dynamic Latch Behavior 21 2.8 Model Implementation 21 2.8.1 Derivation of the Equation Set Up for One Cargo Unit 22 2.9 Simulation Environment 25 3 Full Scale ULD Crash Tests 33 3.1 About this Chapter 33 3.2 Objectives 33 3.3 Test Setup 34 3.3.1 Cargo Configuration 34 3.3.2 Test Configuration 38 3.3.3 Test Equipment 39 4 Analysis of ULD Crash Tests 41 4.1 Test Results 41 4.1.1 Test with frangible Cargo 41 4.1.2 Test with rigid Cargo 45 4.2 Measurement Quality 47 4.3 Load Principles 50 4.4 Load Propagation on Barrier 52 5 Parameter Identification and Results 53 5.1 About this Chapter 53 5.2 Identification Process 53 5.3 Stiffness and Damping Identification 56 5.3.1 Identification of first ULD characteristic 57 5.3.2 Identification of second and aft ULDs 58 5.3.3 Identified Load-De ection Characteristics 59 5.4 Model Validation 60 6 Barrier Protection against Rigid Cargo Impact 63 6.1 About this Chapter 63 6.2 Excitation Pulse 64 6.3 State-of-the-Art Consideration 65 VIII CONTENTS 6.4 Simulation Model based on Energy Method 67 6.5 Reduced Crushable Cargo owing to Rigid Cargo Tests 70 7 Full Scale Latch Rupture Test 74 7.1 About this Chapter 74 7.2 Objectives 75 7.3 Test Setup 76 7.3.1 Tested Cargo 78 7.3.2 Test Measurement 80 8 Analysis of Latch Rupture Test 82 8.1 About this Chapter 82 8.2 Results and Physical Effects 83 8.2.1 Energy Flow Consideration 83 8.2.2 Pulse Consideration 86 8.2.3 Load and Velocity Consideration 86 8.2.4 Summary 91 9 Consolidation of the Two Crash Requirements 92 9.1 Integration of Frangible and Rigid Simulation Model 92 9.2 Linked Simulation Results 92 9.3 Dynamic Impact Loads on Safety Barrier Wall 93 9.4 Minimal Barrier Loads for Safety Barrier Wall Protection 96 9.5 Safety Barrier Wall Design Loads 99 10 Summary and Outlook 101