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Articles 1231 - 1260 of 1384
Full-Text Articles in Mechanics of Materials
Evolutionary Algorithm For The Placement Of Fluid Power Valves On A Valve Stand, Trichy M. Kethara Pasupathy, Ravi Teja Seethamraju, Robert G. Wilhelm
Evolutionary Algorithm For The Placement Of Fluid Power Valves On A Valve Stand, Trichy M. Kethara Pasupathy, Ravi Teja Seethamraju, Robert G. Wilhelm
Department of Mechanical and Materials Engineering: Faculty Publications
The choice of placement of fluid power valves on a valve stand and routing by pipes has an impact on operational costs. Choosing the right placement that provides optimum routing configuration or determining the optimum routing for a chosen placement are both computationally hard problems. An evolutionary algorithm (EA), to minimize operational costs while optimizing placement and routing of valves, is developed here. The best practices in the industry are abstracted and implemented in the EA. In this paper, the algorithm and its performance for examples with varying complexities are presented. Our results meet or exceed experienced designers’ solutions.
Mechanical Behavior Of Cracked Panels Repaired With Bonded Composite Patch, Michael A. Hansen
Mechanical Behavior Of Cracked Panels Repaired With Bonded Composite Patch, Michael A. Hansen
Theses and Dissertations
This research focuses on investigating the mechanical behavior of cracked aluminum panels repaired with bonded boron/epoxy composite patches. The effects of crack initiation and growth on the residual strength of the repaired panels are characterized. This research establishes a correlation between damage modes, residual strength and evolution of strain within as well as outside the patch. Monotonic tensile tests on specimens with a perfectly bonded patch were used to determine the base line strength. Likewise, fatigue tests on specimens with a perfectly bonded patch served to establish baseline fatigue life. In addition, several specimens with a perfectly bonded patch were …
Internal Damage Detection And Assessment In Beams Using Experimental Natural Frequencies, Frances K. Durham
Internal Damage Detection And Assessment In Beams Using Experimental Natural Frequencies, Frances K. Durham
Theses and Dissertations
This study investigated the frequency response of a cantilever beam with the intent of establishing a reliable nondestructive method of damage detection. The test specimens were 12 aluminum 2024 T3 beams, each identical except for a unique, eccentrically located notch, and one reference notchless beam. The machined notches varied in length and location to simulate varying degrees of damage. Laser doppler vibrometry enabled the data acquisition. The changes in natural frequencies were correlated to notch length and notch location. A comparison of eccentric and centered notch influence on the natural frequencies also is discussed.
Tensile Properties Of Martensitic Stainless Steels At Elevated Temperatures, Ajit K. Roy, Srinivasarao R. Kukatla, Bhagath Yarlagadda, V. N. Potluri, Martin Lewis, Brendan O'Toole
Tensile Properties Of Martensitic Stainless Steels At Elevated Temperatures, Ajit K. Roy, Srinivasarao R. Kukatla, Bhagath Yarlagadda, V. N. Potluri, Martin Lewis, Brendan O'Toole
Mechanical Engineering Faculty Research
Tensile properties of quenched and tempered martensitic alloys EP-823, HT-9, and 422 were evaluated at temperatures ranging from ambient to 600 °C as a function of three different tempering times. The results indicated that the yield strength, ultimate tensile strength, and the failure strength were gradually reduced with increasing temperature. The ductility parameters were enhanced at elevated temperatures due to increased plastic flow. However, the tempering time did not significantly influence these properties. The evaluation of the fracture surfaces by scanning electron microscopy revealed reduced cracking and dimpled microstructures, indicating enhanced ductility at higher testing temperatures.
Residual Stress Characterization In Structural Materials By Destructive And Nondestructive Techniques, Ajit K. Roy, Anand Venkatesh, Vikram Marthandam, Satish Dronavalli, Douglas P. Wells, Ronald Rogge
Residual Stress Characterization In Structural Materials By Destructive And Nondestructive Techniques, Ajit K. Roy, Anand Venkatesh, Vikram Marthandam, Satish Dronavalli, Douglas P. Wells, Ronald Rogge
Mechanical Engineering Faculty Research
Transmutation of nuclear waste is currently being considered to transform long-lived isotopes to species with relatively short half-lives and reduced radioactivity through capture and decay of minor actinides and fission products. This process is intended for geologic disposal of spent nuclear fuels for shorter durations in the proposed Yucca Mountain repository. The molten lead-bismuth-eutectic will be used as a target and coolant during transmutation, which will be contained in a subsystem vessel made from materials such as austenitic (304L) and martensitic (EP-823 and HT-9) stainless steels. The structural materials used in this vessel will be subjected to welding operations and …
Analysis Of Computational Methods For The Treatment Of Material Interfaces, Minh C. Nguyen
Analysis Of Computational Methods For The Treatment Of Material Interfaces, Minh C. Nguyen
Theses and Dissertations
Rocket sled tests at the Air Force Research Laboratory's Holloman High Speed Test Track frequently approach velocities where gouging development becomes the limiting factor to achieving higher operating velocities. Direct observation of the gouging process is not possible so computational modeling is necessary to study the phenomenon. Since gouging development is dependent on the impact surface conditions, the method used to model material interfaces directly affects the accuracy of the solution. Three methods are available in the hydrocode CTH to handle material interfaces: 1) materials are joined at the interface, 2) a frictionless slide line is inserted, and 3) a …
Fatigue Behavior Of A Functionally-Graded Titanium Matrix Composite, Scott R. Cunningham
Fatigue Behavior Of A Functionally-Graded Titanium Matrix Composite, Scott R. Cunningham
Theses and Dissertations
Functionally-graded Titanium Matrix Composites are an attempt to utilize the high-strength properties of a titanium matrix composite with a monolithic alloy having the more practical machining qualities. This work studied the mechanical characteristics of the joint region as a first step toward future evaluation of this material. The scope of this effort involved testing under monotonic tension and fatigue loading conditions. Mechanical properties and cyclic behavior were evaluated for the joint area and then compared to those of the parent materials. The results of this study found that the strength of the transition region was slightly higher than the unreinforced …
Tensile Stress Rupture Behavior Of A Woven Ceramic Matrix Composite In Humid Environments At Intermediate Temperature, Kevin J. Larochelle
Tensile Stress Rupture Behavior Of A Woven Ceramic Matrix Composite In Humid Environments At Intermediate Temperature, Kevin J. Larochelle
Theses and Dissertations
Stress rupture tests on the SylramicTM fiber with an in-situ layer of boron nitride, boron nitride interphase, and SiC matrix ceramic matrix composite were performed at 550°C and 750°C with 0.0, 0.2, or 0.6 atm partial pressure of water vapor, pH2O. The 550°C, 100-hr strengths were 75%, 65% and 51% of the monotonic room temperature tensile strength, respectively. At 750°C, the strengths were 67%, 51%, and 49%, respectively. Field Emission Scanning Electron Microscopy analysis estimated the total embrittlement times for 550°C with 0.0, 0.2, and 0.6 atm pH2O were >63 hrs, >38 hrs, and between …
An Investigation Of A Simplified Gouging Model, Gregory S. Rickerd
An Investigation Of A Simplified Gouging Model, Gregory S. Rickerd
Theses and Dissertations
Gouging is a type of structural failure that becomes important when two metals slide against each other at velocities in the range of 1.5 kilometers per second. A computer model has previously been used to model the development of gouging at the Holloman High Speed Test Track. This model has not been experimentally verified to be correct, due to the complexity of the model. This research develops a simplified model that can be experimentally verified. The computer program utilized in this research was studied to determine the most appropriate options to use in simulations. This was accomplished by modeling a …
Electronic Commerce Negotiation In A Supply Chain Via Constraint Evaluation, R. Wilhelm, B. Chu, R. Sun
Electronic Commerce Negotiation In A Supply Chain Via Constraint Evaluation, R. Wilhelm, B. Chu, R. Sun
Department of Mechanical and Materials Engineering: Faculty Publications
Negotiation is of critical importance in e-commerce applications where the supply chain is dynamic and reconfiguring. In this research supply chain negotiation problems are addressed as constraint-satisfaction problems. In general each negotiation is handled in the largest scope possible to avoid the suboptimality that can result from many local solutions. This global approach, however, must be balanced with time constraints that apply in e-commerce supply chain execution. In this paper, we describe a new approach for e-commerce supply chain negotiation via constraint evaluation. As well, results from prototype software, distributed across the internet, are discussed. Beyond the general formulation, we …
Influence Of Composition And Heat-Treatment On The Charge Transport Properties Of Poly(3-Hexylthiophene) And [6,6]-Phenyl C61-Butyric Acid Methyl Ester Blends, Jinsong Huang, Gang Li, Yang Yang
Influence Of Composition And Heat-Treatment On The Charge Transport Properties Of Poly(3-Hexylthiophene) And [6,6]-Phenyl C61-Butyric Acid Methyl Ester Blends, Jinsong Huang, Gang Li, Yang Yang
Department of Mechanical and Materials Engineering: Faculty Publications
Poly(3-hexylthiophene) (P3HT) and [6,6]-phenyl C61-butyric acid methyl ester (PCBM) blends have been demonstrated to form highly efficient polymer photovoltaic devices. In this letter, the time-of-flight technique is used to investigate the influence of composition and heat treatment on charge transport properties of P3HT and PCBM blends. The transport of electrons and holes both display a transition from dispersive to nondispersive and return to dispersive again as the percentage of PCBM increases. A balanced mobility of both electron and hole is obtained at a composition of 1:1 weight ratio, and it is nearly independent of the electrical field in …
Sub-Surface Corrosion Research On Rock Bolt System, Perforated Ss Sheets And Steel Sets For The Yucca Mountain Repository, Dhanesh Chandra, Jaak J.K. Daemen, Jaime Gonzalez, Raymond Keeler, Amy J. Smiecinski
Sub-Surface Corrosion Research On Rock Bolt System, Perforated Ss Sheets And Steel Sets For The Yucca Mountain Repository, Dhanesh Chandra, Jaak J.K. Daemen, Jaime Gonzalez, Raymond Keeler, Amy J. Smiecinski
Publications (YM)
The objective of the proposed investigation is to conduct corrosion research and predict the durability of rock-bolts and other underground metallic roof supports. In critical areas, it is possible to use highly corrosion resistant steels for rock bolts at Yucca Mountain (YM) repository, as the steel rock bolts, as well as other materials such as Bernold type shields for tunnels at YM site [1-4]. In addition, there is propensity for stress corrosion cracking as well as hydrogen induced cracking in rock bolts likely to occur in YM repository emplacement under drift conditions. As corrosion of these materials for underground support …
Stress Corrosion Cracking Resistance Of Martensitic Stainless Steels For Transmutation Applications, Phani P. Gudipati
Stress Corrosion Cracking Resistance Of Martensitic Stainless Steels For Transmutation Applications, Phani P. Gudipati
UNLV Theses, Dissertations, Professional Papers, and Capstones
The susceptibility of Alloy EP-823 to stress corrosion cracking has been evaluated using smooth and notched cylindrical specimens in neutral and acidic solutions at ambient and elevated temperatures using constant load and slow strain rate testing (SSR) techniques. C-ring and U-bend specimens have also been tested in the acidic solution. The effect of hydrogen on the cracking susceptibility has been evaluated under controlled cathodic potential. While no failures were observed with smooth specimens at constant load, the notched specimens showed failure. The SSR test results indicate that the true failure stress (o'f), time to failure and ductility parameters …
Cfd Analysis Of 3-D Thermalhydraulics Flow Effects On Wall Concentration Gradient Profiles For Lbe Loop Fittings, Narain Armbya
Cfd Analysis Of 3-D Thermalhydraulics Flow Effects On Wall Concentration Gradient Profiles For Lbe Loop Fittings, Narain Armbya
UNLV Theses, Dissertations, Professional Papers, and Capstones
The objective of the thesis is to study the effects of thermalhydraulics flows on the wall concentration gradient profiles in LBE loop fittings. To that end detailed models of the fittings have been constructed to study these effects. These fittings include sudden expansion, sudden contraction, t-joint and elbow. The typical flow rates chosen for these simulations are typical of design criteria chosen for the loop with Reynolds numbers expected around 200,000 and the usual axial temperature profiles which are being characterized in the DELTA loop at LANL. STAR-CD is the simulation package used to make these predictions, which include detailed …
Stress Corrosion Cracking And Hydrogen Embrittlement Of Martensitic Alloy Ep-823, Mohammad K. Hossain
Stress Corrosion Cracking And Hydrogen Embrittlement Of Martensitic Alloy Ep-823, Mohammad K. Hossain
UNLV Theses, Dissertations, Professional Papers, and Capstones
This investigation is focused on the evaluation of stress corrosion cracking (SCC), localized corrosion, and hydrogen embrittlement (HE) susceptibility of martensitic Alloy EP-823 in neutral and acidic solutions at ambient and elevated temperatures. While no failures were observed in smooth specimens in the neutral solution, failures were noticed in the 90°C acidic solution at constant-load (CL) leading to a threshold stress (O'th) of 102 ksi. The presence of a notch reduced the O'th value to 91 ksi in a similar environment. The ductility (%El and %RA), time-to-failure (TTF), and true failure stress (O'r) were gradually …
Environmental Effects On Corrosion Properties Of Alloy 22, K. S. Raja, L. G. Mcmillion, Shantanu A. Namjoshi, Paige Russel, Raymond E. Keeler, Amy J. Smiecinski
Environmental Effects On Corrosion Properties Of Alloy 22, K. S. Raja, L. G. Mcmillion, Shantanu A. Namjoshi, Paige Russel, Raymond E. Keeler, Amy J. Smiecinski
Publications (YM)
During the regulatory life of the Yucca Mountain High Level Nuclear Waste (HLNW) repository the primary engineered barrier that is to prevent release of radioactive material into the environment is proposed to be a Corrosion-Resistant Material (CRM) outer shell covering the Waste Package (WP) container. The current selection for the CRM is Alloy 22 (UNS N06022), a Ni-Cr-Mo-W-Fe alloy. Alloy 22 forms a defective chromic oxide passive film which results in excellent corrosion resistance; the presence of molybdenum in Alloy 22 offers corrosion resistance in reducing environments as well as oxidizing environments.
Phase Stability And Segregation In Alloy 22 Base Metal And Weldments, Jeffrey Lacombe, Shantanu A. Namjoshi, Paige Russel, Raymond E. Keeler, Amy J. Smiecinski
Phase Stability And Segregation In Alloy 22 Base Metal And Weldments, Jeffrey Lacombe, Shantanu A. Namjoshi, Paige Russel, Raymond E. Keeler, Amy J. Smiecinski
Publications (YM)
The current design of the waste disposal containers relies heavily on encasement in a multi-layered container, featuring a corrosion barrier of Alloy 22, a Ni-Cr-Mo-W based alloy with excellent corrosion resistance over a wide range of conditions. The fundamental concern from the perspective of the Yucca Mountain Project, however, is the inherent uncertainty in the (very) long-term stability of the base metal and welds. Should the properties of the selected materials change over the long service life of the waste packages, it is conceivable that the desired performance characteristics (such as corrosion reistance) will become compromised, leading to premature failure …
Long-Term Mechanical Behavior Of Yucca Mountain Tuffs, And Its Variability, Jaak J.K. Daemen, George Danko, Jaime Gonzalez, Amy J. Smiecinski, Raymond E. Keeler
Long-Term Mechanical Behavior Of Yucca Mountain Tuffs, And Its Variability, Jaak J.K. Daemen, George Danko, Jaime Gonzalez, Amy J. Smiecinski, Raymond E. Keeler
Publications (YM)
We propose to continue the investigation of the long term strength of Yucca Mountain tuffs, with particular emphasis on tuffs from and near the emplacement horizon. We propose to also continue and expand the investigation of the spatial variability of rock strength and stiffness. An intrinsic component of this planned rock testing is the testing of rock joints. Although the emphasis is on tests aimed at determining long term strength, as part of the testing measurements of stiffness also are collected, and will be collected, reported, and analyzed.
Science For Stewardship: Multidisciplinary Research On Uss Arizona, Matthew A. Russell, Larry E. Murphy, Donald L. Johnson, Timothy J. Foecke, Pamela J. Morris, Raphy Mitchell
Science For Stewardship: Multidisciplinary Research On Uss Arizona, Matthew A. Russell, Larry E. Murphy, Donald L. Johnson, Timothy J. Foecke, Pamela J. Morris, Raphy Mitchell
Department of Mechanical and Materials Engineering: Faculty Publications
The National Park Service’s Submerged Resources Center and USS Arizona Memorial are conducting and coordinating research directed at understanding the nature and rate of natural processes affecting the deterioration of the USS Arizona in Pearl Harbor, Hawaii. The USS Arizona Preservation Project is designed to be multi-year, interdisciplinary and cumulative, with each element contributing to developing an overall management strategy designed to minimize environmental hazard from fuel oil release and provide the basic research required to make informed management decisions for long-term preservation. The primary project focus is toward acquiring requisite data for understanding the complex corrosion and deterioration processes …
Role Of Plasticity On Fretting Fatigue Behavior Of Ti-6al-4v, Kisu Shin
Role Of Plasticity On Fretting Fatigue Behavior Of Ti-6al-4v, Kisu Shin
Theses and Dissertations
Fretting fatigue generally leads to the degradation of the fatigue strength of a material due to cyclic micro-slip between two contacting materials. Fretting fatigue is regarded as an important issue in designing aerospace structures. While many studies have evaluated fretting fatigue behavior under elastic deformation conditions, few studies have focused on fretting fatigue behavior under elastic-plastic deformation conditions. The primary goal of this study was to characterize the fretting fatigue crack initiation behavior in the presence of plasticity. Experimental tests were performed using pad configurations involving elastic-plastic deformations. In order to calculate stress distributions under elastic-plastic fretting fatigue conditions, FEA …
Embrittlement And Localized Corrosion In Alloy Ht-9, Sudheer Sama
Embrittlement And Localized Corrosion In Alloy Ht-9, Sudheer Sama
UNLV Theses, Dissertations, Professional Papers, and Capstones
This investigation is focused on the evaluation of stress corrosion cracking (SCC), hydrogen embrittlement (HE) and localized corrosion susceptibility of Alloy HT -9 in neutral and acidic solutions at 30, 60 and 90°C. Constant-load and slow-strain-rate (SSR) testing techniques were used to evaluate the SCC and HE behavior of this alloy by using smooth and notched tensile specimens. Hydrogen effect on the cracking behavior was evaluated by applying cathodic (negative) potential to the test specimens. Localized corrosion susceptibility was evaluated by cyclic potentiodynamic polarization technique. The results of constant load SCC testing showed a threshold stress at 80% of the …
Environment-Induced Degradations In A Target Structural Material For Transmutation Applications, Ramprashad Prabhakaran
Environment-Induced Degradations In A Target Structural Material For Transmutation Applications, Ramprashad Prabhakaran
UNLV Theses, Dissertations, Professional Papers, and Capstones
This investigation is focused on the evaluation of stress corrosion cracking (SCC) and localized corrosion behavior of Type 422 stainless steel in aqueous environments at ambient and elevated temperature. The results of constant load SCC testing using smooth specimens showed no failure in the neutral solution but a threshold stress of 97 ksi was observed in the 90°C acidic environment. SCC testing by the slow-strain-rate test method indicate that the time-to-failure, true failure stress and ductility parameters were gradually reduced with increasing temperature, showing more pronounced effect in the acidic solution. The application of a controlled cathodic potential showed further …
Modeling, Optimization, And Flow Visualization Of Chemical Etching Process In Niobium Cavities, Sathish K. Subramanian
Modeling, Optimization, And Flow Visualization Of Chemical Etching Process In Niobium Cavities, Sathish K. Subramanian
UNLV Theses, Dissertations, Professional Papers, and Capstones
Niobium cavities are important component of the linear accelerators. Researchers have concluded that buffered chemical polishing on the inner surface of the cavity improves its performance. However the mechanism of chemical polishing is not well understood. A finite element computational fluid dynamics (CFD) model was developed to simulate the fluid flow characteristics of chemical etching process inside the cavity. The CFD model is then used to optimize the baffle design. The analysis confirmed the observation of other researchers that the iris section of the cavity received more etching than the equator regions. The baffle, which directs flow towards the walls …
Analytical Results For A Single-Unit System Subject To Markovian Wear And Shocks, Daniel E. Finkelstein
Analytical Results For A Single-Unit System Subject To Markovian Wear And Shocks, Daniel E. Finkelstein
Theses and Dissertations
This thesis develops and analyzers a mathematical model for the reliability measures of a single-unit system subject to continuous wear due to its operating environment and randomly occurring shocks that inflict a random amount of damage to the unit. Assuming a Markovian operating environment and shock arrival mechanism, Laplace-Stieltjes transform expressions are obtained for the failure time distribution and all of its moments. Moreover, an analytical expression is derived for the long-run availability of the single-unit system when it is subject to an inspect-and-replace maintenance policy. The analytical results are illustrated, and their results compared with those of Monte Carlo-simulated …
Optimization Process For Configuration Of Flexible Joined-Wing, Cody C. Rasmussen
Optimization Process For Configuration Of Flexible Joined-Wing, Cody C. Rasmussen
Theses and Dissertations
This study established a weight optimized configuration design of a joined-wing sensor-craft. The joined-wing aircraft concept fulfills a proposed long-endurance surveillance mission that contains an antenna structure embedded in the wing skin. The analysis was completed utilizing structural optimization, aerodynamic analyses, and response surface methodology. A sample of 62 joined-wing configurations were weight optimized. Each optimized structure was determined through a change of skin, spar, and rib thickness in the wing box by determining trimmed maneuver and gust conditions for critical flight mission points. Since the joined-wing concept has non-linear deformation characteristics, the structural optimization used both strain and buckling …
An Electromagnetic Tool For Damping And Fatigue Analysis, Todd M. Hoover
An Electromagnetic Tool For Damping And Fatigue Analysis, Todd M. Hoover
Theses and Dissertations
An automated test system was developed by the USAF Turbine Engine Fatigue Facility (TEFF). This system was initially designed to reduce the time and manpower required to characterize damping treatments. It is based on a digitally controlled environmental chamber with automated data acquisition and processing. Several outputs are available including identification of natural frequencies, modal damping ratios from the acquired frequency responses, and changes in damping with response amplitude; however, the TEFF additionally desires the capability to study fatigue under a free boundary condition. The system consists of a test specimen suspended by a pendulum to closely simulate free boundary …
Effect Of A Variable Contact Load On Fretting Fatigue Behavior Of Ti-6al-4v, Andrew J. Jutte
Effect Of A Variable Contact Load On Fretting Fatigue Behavior Of Ti-6al-4v, Andrew J. Jutte
Theses and Dissertations
Effects of a variable contact load on the high cycle fretting fatigue behavior of Ti-6AL-4V were investigated. Experimental tests were performed using a new test setup capable of applying a contact load varying in amplitude, frequency, and phase and independently measuring shear forces on opposite sides of a specimen. Finite element analysis (FEA) of experimental and idealized loading conditions was performed and local mechanistic parameters and the Modified Shear Stress Range (MSSR) fatigue parameter were determined. Correlations between contact width, slip amplitude, fatigue life and a variable contact load were established with variable contact loading shown to have a damaging …
The Evaluation Of The Damping Characteristics Of A Hard Coating On Titanium, Christopher M. Blackwell
The Evaluation Of The Damping Characteristics Of A Hard Coating On Titanium, Christopher M. Blackwell
Theses and Dissertations
Engine failures due to fatigue have cost the Air Force an estimated $400 million dollars per year over the past two decades (Garrison, 2001). Damping treatments capable of reducing the internal stresses of fan and turbine blades to levels where fatigue is less likely to occur have the potential for reducing cost while enhancing reliability. This research evaluates the damping characteristics of magnesium aluminate spinel, MgO+Al2O3, (mag spinel) on titanium plates. The material and aspect ratio were chosen to approximate the low aspect ratio blades found in military gas turbine fans. The plates were tested with …
Bar Clamp Having Ergonomic Handle, M. Susan Hallbeck, Myung-Chul Jung
Bar Clamp Having Ergonomic Handle, M. Susan Hallbeck, Myung-Chul Jung
Department of Mechanical and Materials Engineering: Faculty Publications
The present invention generally relates to a handle assembly for a hand operable bar clamp having a fixed jaw, a movable jaw and a drive for translating the movable jaw towards the fixed jaw. The assembly includes a handgrip and a trigger handle. The handgrip having an elongated rear portion has a generally rounded surface and being contoured to complement the natural transverse curve pf a human palm. The trigger handle is pivotal with respect to the handgrip. The trigger handle included an elongated front portion having a rounded front surface and being contoured to complement the natural palmer curve …
Trailer Mounted Bursting Energy Absorption System, John D. Reid, John R. Rohde, Dean L. Sicking
Trailer Mounted Bursting Energy Absorption System, John D. Reid, John R. Rohde, Dean L. Sicking
Department of Mechanical and Materials Engineering: Faculty Publications
A portable crash attenuation System having a trailer frame and an energy absorption mechanism attached thereto. The absorption mechanism has a first Stage pivotably connected to a Second Stage and the Second Stage is pivotably connected to the frame. By pivoting the Stages about hinges the attenuation System may be folded from an extended, deployed position or mode to a shortened transit mode for easy relocation of the entire attenuation System.