Download or read book Experimental and Numerical Simulations of Explosive Loading on Structural Components written by Peter N. Huson and published by . This book was released on 2012 with total page 214 pages. Available in PDF, EPUB and Kindle. Book excerpt: The extreme loading conditions produced from the detonation of an explosive are severely detrimental to structures and structural components. These effects are amplified when a blast occurs in an enclosed or confined geometry, where reduced ventilation and oblique angles result in extended pulse durations and added reflections of generated pressures. The objective of this dissertation is to develop experimental methodologies and numerical assessment tools to document and simulate failure sequences in composite sandwich connections under simulated internal blast loads. The experimental research was conducted using the UCSD Blast Simulator, a one-of-a-kind system able to simulate explosive events without the use of explosive materials and therefore without the associated fireballs. This is accomplished with an array of high velocity hydraulic actuators driven by a combined high pressure nitrogen/hydraulic energy source. In explosive field testing, video and data from instrumentation is often lost to the destructive nature of the blast environment. The simulator allows for the generation of high fidelity data that documents the response and failure progression in structural members, which in turn lends researchers the ability to develop and test damage mitigation strategies as well as design guidelines for critical infrastructure subject to impulsive loads. First, the development of loading protocols were presented, in which pressures of prolonged durations distributed in multiple directions were achieved through the impact of high strength water filled bladders. These methods were then implemented in the testing of 90 degree composite sandwich joint specimens, which were reacted via adjustable steel gripping fixtures mounted in configurations suitable for impact with the high powered Blast Generators. In an effort to create a numerical model capable of simulating the failure modes observed in the Blast Simulator experiments, a series of individual component tests were conducted to assist in the calibration of finite element material models. The characterization of the CFRP facesheet/balsa wood core sandwich material's failure properties in bending, shear and delamination were documented experimentally and validated numerically using LS-DYNA under both quasi-static and dynamic load rates. Finally, the updated material models were implemented into the simulation of the Composite Joint Tests, which highlight the key mechanisms involved in connection failure and ultimately joint breach. The studies found that failure of the connection structure were functions of the bond strength between the panel facesheets and overlaminate used to adhere the sandwich panels together, strongly coupled with the shear capacity of the individual panel cores. Recommendations for improved joint design were made and suggestions for extrapolation of the developed technologies to larger scale testing were offered.

Download or read book Experimental Simulations of Explosive Loading on Structural Components written by Tonatiuh Rodríguez-Nikl and published by . This book was released on 2006 with total page 252 pages. Available in PDF, EPUB and Kindle. Book excerpt: The dissertation responds to the need for efficient techniques for testing and validating protective technologies to resist explosive loading on civil structures; the newly-developed Explosive Loading Laboratory allows investigators to simulate explosive blast loading at a lower cost and with better data than when using real explosives. Analytical tools are developed for the new laboratory and comparisons between real and simulated explosive tests confirm that the two are equivalent. These developments provide future investigators with confidence in the simulated blast methodology and tools to predict results and analyze the data, thus setting the stage for decades of fruitful research in a nascent field of simulated explosive testing. The simulated blast load is applied via specially designed apparatuses called blast generators, each of which is made of a high speed actuator that accelerates an impacting module towards the specimen. An elastomeric pad, called the programmer, on the front of the impacting module provides a blast-like pressure pulse to the specimen. The entire setup is housed in a post-tensioned, self-reacting, reinforced concrete reaction structure. An inaugural series of tests on column specimens provides data on structural behavior and on the functioning of the laboratory. New methods of data analysis are developed: the equivalent uniform load method reduces the load recorded on multiple channels to a single, rationally-derived value, and the equivalent charge method translates the experimental results to an equivalent real scenario. Because there is no fireball to obscure the specimen during the blast, the verbal descriptions and video stills herein are the first-ever visual record of structural behavior under blast loading. The laboratory results are corroborated with field test data via qualitative comparisons and demand-damage plots to demonstrate the validity of simulated blast testing. A methodology is developed for quickly and easily determining the necessary velocity of the impacting module to deliver a desired impulse to the specimen. Load-deformation programmer data are collected and a phenomenological model of programmer behavior is derived for use in detailed pre-test analyses, including finite element implementations. Both tools are derived theoretically, calibrated to experimental data, and verified against independent experimental data.

Download or read book Explosions in Air written by Wilfred Edmund Baker and published by . This book was released on 1973 with total page 298 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Design Against Blast written by S. Syngellakis and published by WIT Press. This book was released on 2013 with total page 225 pages. Available in PDF, EPUB and Kindle. Book excerpt: Terrorist attacks and other destructive incidents caused by explosives have, in recent years, prompted considerable research and development into the protection of structures against blast loads. For this objective to be achieved, experiments have been performed and theoretical studies carried out to improve our assessments of the intensity as well as the space-time distribution of the resulting blast pressure on the one hand and the consequences of an explosion to the exposed environment on the other.This book aims to enhance awareness on and understanding of these topical issues through a collection of relevant, Transactions of the Wessex Institute of Technology articles written by experts in the field. The book starts with an overview of key physics-based algorithms for blast and fragment environment characterisation, structural response analyses and structural assessments with reference to a terrorist attack in an urban environment and the management of its inherent uncertainties.A subsequent group of articles is concerned with the accurate definition of blast pressure, which is an essential prerequisite to the reliable assessment of the consequences of an explosion. Other papers are concerned with alternative methods for the determination of blast pressure, based on experimental measurements or neural networks. A final group of articles reports investigations on predicting the response of specific structural entities and their contents.The book concludes with studies on the effectiveness of steel-reinforced polymer in improving the performance of reinforced concrete columns and the failure mechanisms of seamless steel pipes used in nuclear industry.

Download or read book Numerical Simulations for Classification of Blast Loaded Laminated Glass written by Alexander Stolz and published by . This book was released on 2014 with total page 35 pages. Available in PDF, EPUB and Kindle. Book excerpt: It is important to protect critical buildings (shopping centres, government buildings and embassies), infrastructure and utilities, train and underground stations against being damaged, destroyed or disrupted by deliberate acts of terrorism, criminal activity and malicious behaviour. Normal regulations and building guidelines do not generally take into account these threats. The introduction of appropriate regulations or guidelines, where deemed necessary, should, enhance the resilience of buildings and infrastructure against explosion incidents. In order to protect the built infrastructure, methods are required to quantify the resistance of structural components against explosive loading and to assess the hazards resulting from the failure of an element. The applicable state-of-the-art techniques may include either experimental or numerical methods, or a combination of both.^Therefore, the thematic group (TG) on the resistance of structures to explosion effects was formed in order to bring the required expertise together, make it commonly available and to find and define harmonised methods and solutions which can be provided to the decision-makers responsible for critical infrastructure protection. The current report summarizes existing best practices for the numerical finite element modelling of blast loading, including the important topics of domain discretisation, implicit/explicit formulation, Lagrangian/Eulerian solvers, the mathematical description of the material behaviour etc. Furthermore recommendations for the modelling of laminated glass elements are formulated and knowledge gaps in this application area are pointed out. Hence the report builds the basis for an actual evaluation of the different numerical methods, their suitability to certain problems, and their capability to support/complement the experimental testing of glass components.^It thus provides helpful information to design architects and engineers, and more generally to critical infrastructure stakeholders, responsible for the structural integrity and security of the infrastructure in case of an explosion.

Download or read book Explosive Loading of Engineering Structures written by P.S. Bulson and published by CRC Press. This book was released on 1997-07-24 with total page 269 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book reviews the development of research into the explosive loading of structures, mainly since the beginning of the twentieth century. Major contributions in the fields of measurement, analysis and prediction are discussed. Dynamic loading from conventional high explosives is examined, as well as the effects of liquid propellant, dust, gas, v

Download or read book Explosion Systems with Inert High Modulus Components written by Igor A. Balagansky and published by John Wiley & Sons. This book was released on 2019-06-12 with total page 224 pages. Available in PDF, EPUB and Kindle. Book excerpt: Describes in one volume the data received during experiments on detonation in high explosive charges This book brings together, in one volume, information normally covered in a series of journal articles on high explosive detonation tests, so that developers can create new explosive technologies. It focuses on the charges that contain inert elements made of materials in which a sound velocity is significantly higher than a detonation velocity. It also summarizes the results of experimental, numerical, and theoretical investigations of explosion systems, which contain high modulus ceramic components. The phenomena occurring in such systems are described in detail: desensitization of high explosives, nonstationary detonation processes, energy focusing, and Mach stems formation. Formation of hypersonic flows of ceramic particles arising due to explosive collapse of ceramic tubes is another example of the issues discussed. Explosion Systems with Inert High Modulus Components: Increasing the Efficiency of Blast Technologies and Their Applications also looks at the design of explosion protective structures based on high modulus ceramic materials. The structural transformations, caused in metallic materials by the energy focusing, or by the impact of hypersonic ceramic jets are also discussed. These transformations include, but not limited to adiabatic shear banding, phase transformations, mechanical twinning, melting, boiling, and even evaporation of the impacted substrates. Specifically discusses in one volume the explosions involved with inert high modules components normally scattered over numerous journal articles Covers methods to increase energy output of a weak explosive by encasing it in a higher explosive Discusses the specifics of explosive systems containing high modulus inert elements Details the process of detonation and related phenomena, as well as the design of novel highly performant explosive systems Describes the transformation in materials impacted due to explosion in such systems Explosion Systems with Inert High Modulus Components will be of great interest to specialists working in fields of energy of the explosion and explosion safety as well as university staff, students, and postgraduate students studying explosion phenomena, explosive technologies, explosion safety, and materials science.

Download or read book EASEC16 written by Chien Ming Wang and published by Springer Nature. This book was released on 2020-12-22 with total page 2093 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book presents articles from The 16th East Asian-Pacific Conference on Structural Engineering and Construction, 2019, held in Brisbane, Australia. It provides a forum for professional engineers, academics, researchers and contractors to present recent research and developments in structural engineering and construction.​

Download or read book Explosive Bonding written by V. D. Linse and published by . This book was released on 1967 with total page 38 pages. Available in PDF, EPUB and Kindle. Book excerpt: Describes basic mechanics of the process, practices of those in the field, metal combinations and configurations that have been bonded, and applications.

Download or read book Issues in Structural and Materials Engineering 2011 Edition written by and published by ScholarlyEditions. This book was released on 2012-01-09 with total page 2985 pages. Available in PDF, EPUB and Kindle. Book excerpt: Issues in Structural and Materials Engineering: 2011 Edition is a ScholarlyEditions™ eBook that delivers timely, authoritative, and comprehensive information about Structural and Materials Engineering. The editors have built Issues in Structural and Materials Engineering: 2011 Edition on the vast information databases of ScholarlyNews.™ You can expect the information about Structural and Materials Engineering in this eBook to be deeper than what you can access anywhere else, as well as consistently reliable, authoritative, informed, and relevant. The content of Issues in Structural and Materials Engineering: 2011 Edition has been produced by the world’s leading scientists, engineers, analysts, research institutions, and companies. All of the content is from peer-reviewed sources, and all of it is written, assembled, and edited by the editors at ScholarlyEditions™ and available exclusively from us. You now have a source you can cite with authority, confidence, and credibility. More information is available at http://www.ScholarlyEditions.com/.

Download or read book Numerical Simulation of a Long Span Bridge Response to Blast Loading written by Edmond Kai Cheong Tang and published by . This book was released on 2009 with total page 237 pages. Available in PDF, EPUB and Kindle. Book excerpt: [Truncated abstract] As a consequence of the increase in terrorist incidents, many comprehensive researches, both experimental and numerical modelling of structure and blast interaction, have been conducted to examine the behaviour of civilian structures under dynamic explosion and its impact. Nevertheless most of the works in literature are limited to response of simple structures such as masonry walls, reinforced concrete beams, columns and slabs. Although these studies can provide researchers and structural engineers a good fundamental knowledge regarding blast load effect, it is more likely for blast load to act upon entire structures in actual explosion events. The interaction between blast load and structures, as well as the interaction among structural members may well affect the structural response and damage. Therefore it is necessary to analyse more realistic reinforced concrete structures in order to gain an extensive knowledge on the possible structural response under blast load effect. Among all the civilian structures, bridges are considered to be the most vulnerable to terrorist threat and hence detailed investigation in the dynamic response of these structures is essential. This thesis focuses on the study of the response of a modern cable-stayed bridge under blast loadings. ... Firstly, analysis is conducted to examine the failure of four main components namely pier, tower, concrete back span and steel composite main span under close proximity dynamic impact of a 1000 kg TNT equivalent blast load. Secondly, based on such results, the remainder of the bridge structure is then tested by utilizing the loading condition specified in the US Department of Defence (DoD) guideline with the aim to investigate the possibility of bridge collapse after the damage of these components. It is found that failure of the vertical load bearing elements (i.e. pier and tower) will lead to catastrophic collapse of the bridge. Assuming that terrorist threat cannot be avoided, hence protective measures must be implemented into the bridge structure to reduce the damage induced by explosive blast impact and to prevent bridge from collapse. As such, a safe standoff distance is determined for both the pier and tower under the blast impact of 10000 kg TNT equivalent. This information would allow the bridge designer to identify the critical location for placing blast barriers for protection purpose. For the case of bridge deck explosion, carbon fibre reinforced polymer (CFRP) is employed to examine in respect of its effectiveness in strengthening the concrete structure against blast load. In this research, appropriate contact is employed for the numerical model to account for the epoxy resin layer between the CFRP and concrete. In addition, to ensure that the CFRP can perform to its full capacity, anchors are also considered in the numerical study to minimize the chance of debonding due to the weakening of the epoxy. The results reveal that although severe damage can still be seen for locations in close proximity to the explosive charge, the use of CFRP did reduce the dynamic response of the bridge deck as compared to the unprotected case scenario. Further investigation is also carried out to examine the change in damaged zone and global response through variation in CFRP thickness.

Download or read book Structural Design for Dynamic Loads written by Charles Head Norris and published by . This book was released on 1959 with total page 453 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Numerical Modeling of Explosives and Propellants written by Charles L. Mader and published by CRC Press. This book was released on 2007-10-18 with total page 539 pages. Available in PDF, EPUB and Kindle. Book excerpt: Major advances, both in modeling methods and in the computing power required to make those methods viable, have led to major breakthroughs in our ability to model the performance and vulnerability of explosives and propellants. In addition, the development of proton radiography during the last decade has provided researchers with a major new experimental tool for studying explosive and shock wave physics. Problems that were once considered intractable – such as the generation of water cavities, jets, and stems by explosives and projectiles – have now been solved. Numerical Modeling of Explosives and Propellants, Third Edition provides a complete overview of this rapidly emerging field, covering basic reactive fluid dynamics as well as the latest and most complex methods and findings. It also describes and evaluates Russian contributions to the experimental explosive physics database, which only recently have become available. This book comes with downloadable resources that contain— · FORTRAN and executable computer codes that operate under Microsoft® Windows Vista operating system and the OS X operating system for Apple computers · Windows Vista and MAC compatible movies and PowerPoint presentations for each chapter · Explosive and shock wave databases generated at the Los Alamos National Laboratory and the Russian Federal Nuclear Centers Charles Mader’s three-pronged approach – through text, computer programs, and animations – imparts a thorough understanding of new computational methods and experimental measuring techniques, while also providing the tools to put these methods to effective use.

Download or read book Blast Mitigation written by Arun Shukla and published by Springer Science & Business Media. This book was released on 2013-07-06 with total page 368 pages. Available in PDF, EPUB and Kindle. Book excerpt: Blast Mitigation: Experimental and Numerical Studies covers both experimental and numerical aspects of material and structural response to dynamic blast loads and its mitigation. The authors present the most up-to-date understanding from laboratory studies and computational analysis for researchers working in the field of blast loadings and their effect on material and structural failure, develop designs for lighter and highly efficient structural members for blast energy absorption, discuss vulnerability of underground structures, present methods for dampening blast overpressures, discuss structural post blast collapse and give attention to underwater explosion and implosion effects on submerged infrastructure and mitigation measures for this environment.

Download or read book Experimental and Numerical Correlation of a Scaled Containment Vessel Subjected to an Internal Blast Load written by and published by . This book was released on 1997 with total page 29 pages. Available in PDF, EPUB and Kindle. Book excerpt: Los Alamos National Laboratory is currently in the design phase of a large Containment System that will be used to contain hydrodynamic experiments. The system in question is being designed to elastically withstand a 50 kg internal high explosive (PBX-9501) detonation. A one-tenth scaled model of the containment system was fabricated and used to obtain experimental results of both pressure loading and strain response. The experimental data are compared with numerical predictions of pressure loading and strain response obtained from an Eulerian hydrodynamic code (MESA-2D) and an explicit, non-linear finite element code (LLNL DYNA3D). The two-dimensional pressure predictions from multiple hydrodynamic simulations are used as loading in the structural simulation. The predicted pressure histories and strain response compare well with experimental results at several locations.

Download or read book Experimental Mechanics and Effects of Intensive Loading written by Lin Wang and published by Trans Tech Publications Ltd. This book was released on 2015-08-06 with total page 368 pages. Available in PDF, EPUB and Kindle. Book excerpt: Collection of selected, peer reviewed papers from the 2014 SEM Fall Conference and International Symposium on Intensive Loading and Its Effects, October 19-22, 2014, Beijing, China. The 46 papers are grouped as follows: Chapter 1: Plenary and Invited Talks; Chapter 2: Mechanical Properties of Materials; Chapter 3: Materials and Structures under Extreme Loading Conditions; Chapter 4: Computational Experiments and Simulation; Chapter 5: Advanced Diagnostic and Measurement Methods

Download or read book Computational and Experimental Simulations in Engineering written by Shaofan Li and published by Springer Nature. This book was released on with total page 1358 pages. Available in PDF, EPUB and Kindle. Book excerpt: