Download or read book Transportation Loads Measurement and Evaluation of Dynamic Mechanical Loads Data Evaluation written by British Standards Institute Staff and published by . This book was released on 2008-01-31 with total page 62 pages. Available in PDF, EPUB and Kindle. Book excerpt: Transportation, Freight transport, Materials handling, Packaging, Packages, Loading, Dynamic loading, Mechanical measurement, Mechanical testing, Environmental testing, Data processing, Data analysis, Signals

Download or read book Transportation Loads Measurement and Evaluation of Dynamic Mechanical Loads Data Validity Check and Data Editing for Evaluation written by British Standards Institute Staff and published by . This book was released on 2008-01-31 with total page 36 pages. Available in PDF, EPUB and Kindle. Book excerpt: Transportation, Freight transport, Materials handling, Packaging, Packages, Loading, Dynamic loading, Mechanical measurement, Mechanical testing, Environmental testing, Data processing, Signals, Error detection

Download or read book Transportation Loads Measurement and Evaluation of Dynamic Mechanical Loads General Requirements written by British Standards Institute Staff and published by . This book was released on 2008-01-31 with total page 12 pages. Available in PDF, EPUB and Kindle. Book excerpt: Transportation, Freight transport, Materials handling, Packaging, Packages, Loading, Dynamic loading, Mechanical measurement, Mechanical testing, Environmental testing, Data processing, Data acquisition, Test equipment

Download or read book Transportation Loads Measurement and Evaluation of Dynamic Mechanical Loads Data Acquisition and General Requirements for Measuring Equipment written by British Standards Institute Staff and published by . This book was released on 2008-01-31 with total page 64 pages. Available in PDF, EPUB and Kindle. Book excerpt: Transportation, Freight transport, Materials handling, Packaging, Packages, Loading, Dynamic loading, Mechanical measurement, Mechanical testing, Environmental testing, Data processing, Data acquisition, Test equipment, Reports

Download or read book Evaluation Findings for Tekton Inc Steel Rubber Bearings written by Highway Innovative Technology Evaluation Center (U.S.) and published by ASCE Publications. This book was released on 1998-01-01 with total page 52 pages. Available in PDF, EPUB and Kindle. Book excerpt: Prepared by the Highway Innovative Technology Evaluation Center (HITEC), a CERF Service Center. This report summarizes the results of a detailedØevaluation of steel rubber bearings,Ømanufactured by Tekton, Inc. The report is part of a program to test the performance of 11 seismic isolators and dampers produced by several manufacturers. The devicesØwere tested for stability, response during earthquake simulations, and fatigue and weathering effects.

Download or read book Live Load Test and Failure Analysis for the Steel Deck Truss Bridge Over the New River in Virginia written by and published by . This book was released on 2009 with total page 104 pages. Available in PDF, EPUB and Kindle. Book excerpt: This report presents the methods used to model a steel deck truss bridge over the New River in Hillsville, Virginia. These methods were evaluated by comparing analytical results with data recorded from 14 members during live load testing. The research presented herein is part of a larger endeavor to understand the structural behavior and collapse mechanism of the erstwhile I-35W bridge in Minneapolis, Minnesota, that collapsed on August 1, 2007. Objectives accomplished toward this end include investigation of lacing effects on built-up member strain measurement, live load testing of a steel truss bridge, and evaluation of modeling techniques in comparison to recorded data. The most accurate model was used to conduct a failure analysis with the intent of then loading the steel truss bridge to failure. Before any live load testing could be performed, it was necessary to confirm an acceptable strain gage layout for measuring member strains. The effect of riveted lacing in built-up members was investigated by constructing a two-thirds mockup of a typical bridge member. The mockup was instrumented with strain gages and subjected to known loads to determine the most effective strain gage arrangement. The results of the testing analysis showed that for a built-up member consisting of laced channels, one strain gage installed on the middle of the extreme fiber of each channel's flanges was sufficient. Thus, laced members on the bridge were mounted with four strain gages each. Data from live loads were obtained by loading two trucks to 25 tons each. Trucks were positioned at eight locations on the bridge in four different relative truck positions. Data were recorded continuously and reduced to member forces for model validation comparisons. Deflections at selected truss nodes were also recorded for model validation purposes. The model validation process began by developing four simple truss models, each reflecting different expected restraint conditions, in the hopes of bracketing data from recorded results. The models included a simple truss model, a frame model with only the truss members, and a frame model that included the stringers. The final, most accurate model was selected and used for a failure analysis. This model showed where the minimum amount of load could be applied to learn about the bridge's failure behavior and was to be used for a test to be conducted at a later time. Unfortunately, the project was terminated because of a lack of funding before the actual test to failure of the steel truss bridge was conducted. Nevertheless, findings from the study led to two important recommendations: 1.) When instrumenting a steel truss bridge for load testing by placing strain gages on built-up members, four gages, one placed on each flange of each channel, should be used. 2.) When modeling deck truss bridges, the system should be considered to be a frame and should include the stringers in the model.

Download or read book ASME 70 WA NE 2 written by Chi-Wen Lin and published by . This book was released on 1970 with total page 4 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1994 with total page 836 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Live load Models for Design and Fatigue Evaluation of Highway Bridges written by and published by . This book was released on 2007 with total page 333 pages. Available in PDF, EPUB and Kindle. Book excerpt: New load design factors and models are introduced to account for site-specific live-load demands in the state of New Jersey. Live-load for highway bridges is highly site specific. The current AASHTO LRFD design specifications provide a notional design truck to which load factors are applied. These strength design factors were calibrated using reliability theory to provide a consistent level of safety for various spans and bridge types. The original calibration was done using a small sample of data from decades ago. Truck weights and volumes have significantly increased, reducing the level of safety of highway bridges designed today. Live-load is quantified using an extensive weigh-in-motion (WIM) database for the state of New Jersey as well as instrumentation at a bridge located in the heart of Port Newark, NJ. An integrated system combines a WIM system to measure truck loads and a data logger to capture the strains and deflections. This, first of its kind, system provides a complete picture of bridge behavior. The WIM data collected include all of the parameters needed to quantify truck loading: gross and axle weights, axle spacings, classification, counts, speeds, lane, etc. The bridge response includes parameters such as: strains and deflections. Information on truck loads are used to develop load effect envelopes for various span lengths. The load effects are then extrapolated using Normal probability paper to predict the maximum expected levels for the full service life of 75 years. The effect of other distributions, various measurement durations, and truck multiple presence is also studied. Based on the analysis of moment and shear envelops for various spans, it was found that the current load factors must be increased to maintain the level of safety that the code dictates. A new load model is proposed to provide a more uniform bias for New Jersey trucks. Fatigue load effects are studied in terms of effective truck weights, truck dimensions, and multiple presence in comparison with current evaluation procedures. Experimental load and response data from the instrumented bridge along with computer models is used to study the effect of truck weight, volume, and multiple presence of the fatigue life. Statistical techniques developed by the automotive industry are applied to short experimental measurements to predict a fatigue load profile that would be expected if measurement extended to a much longer duration. The rainflow extrapolation techniques utilize Extreme Value Theory and non-parametric smoothing methods to render a future prediction of the rainflow counted stress cycle matrix. The effect of measurement duration, seasonality, and truck multiple presence on fatigue life prediction is studied.

Download or read book Report written by and published by . This book was released on 1964 with total page 112 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Dynamic Pavement Deflection Measurements written by Vernon J. Marks and published by . This book was released on 1977 with total page 34 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Bulletin of the Atomic Scientists written by and published by . This book was released on 1970-06 with total page 116 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Bulletin of the Atomic Scientists is the premier public resource on scientific and technological developments that impact global security. Founded by Manhattan Project Scientists, the Bulletin's iconic "Doomsday Clock" stimulates solutions for a safer world.

Download or read book Load Rating and Evaluation of Two Prestressed Concrete Box Girder Bridges with No Plans Using Non destructive Load Testing written by Dagmawie Degif Shikurye and published by . This book was released on 2014 with total page 436 pages. Available in PDF, EPUB and Kindle. Book excerpt: Bridges with no plans are currently an issue in various states including New Mexico as many exist throughout the United States. Since these bridges have no existing plans and documentation, conventional load rating procedures can't be employed. Therefore in this research project, a four step procedure was developed for the load rating of prestressed concrete box girder bridges without plans. First, the total number and eccentricity of the prestressing strands in the bridge beams are estimated using Magnel diagrams. Second, material properties are obtained from the AASHTO Manual for Bridge Evaluation, AASHTO Standard Specifications, and/or the New Mexico provisions. Second, a Hilti PS 250 Ferroscan is used to detect the steel in the prestressed concrete beams and check the strand estimate and also determine the layout of the shear reinforcement. In addition, the concrete strength is estimated using a Windsor probe. Third, a diagnostic load test is performed to evaluate the in-service behavior and to measure the beam strains under a truck load approximately 60% of the target proof load determined based on the prestressing strand estimate and allowable tensile stress at service. Strain measurements are taken at critical locations to monitor the bridge response during the test. The objectives of this test are to determine the critical transverse truck path (i.e., ones producing the largest measured strains) and compare the measurements with analytical predictions. Fourth, a proof load test is conducted following the critical truck paths and under increasing truck loading until the allowable tensile stress or the target proof load is reached (whichever comes first). Results from the proof test are used to determine rating factors for legal loads. The AASHTOWare BrR software program is also used for purpose of comparison with the rating factors from the proof test. Two prestressed concrete box girder bridges in New Mexico located in Doña Ana County (Bridge 7722) and Bernalillo County (Bridge 8825) were evaluated in this study. For Bridge 7722, the BrR design ratings under HS-20 truck loading were computed as 1.073 and 1.791 at the inventory and operating level, respectively. Inventory and operating factors of 0.882 and 1.403, respectively, were obtained for Bridge 8825. These results, in particular the operating ratings greater than 1.0, provided the needed confidence to proceed with the load tests. Based on the results of the proof tests, rating factors were computed for New Mexico and AASHTO legal loads according to the AASHTO Manual for Bridge Evaluations. The lowest rating factors were 1.09 and 1.17 for Bridge 7722 and Bridge 8825, respectively, which showed that the two bridges did not need to be load posted for legal loads.

Download or read book Split Hopkinson Kolsky Bar written by Weinong W. Chen and published by Springer Science & Business Media. This book was released on 2010-11-11 with total page 390 pages. Available in PDF, EPUB and Kindle. Book excerpt: The authors systematically describe the general principles of Kolsky bars, or split Hopkinson bars, which are widely used for obtaining dynamic material properties. Modifications are introduced for obtaining reliable data. Specific experiment design guidelines are provided to subject the specimen to desired testing conditions. Detailed Kolsky-bar examples are given for different classes of materials (brittle, ductile, soft, etc) and for different loading conditions (tension, torsion, triaxial, high/low temperatures, intermediate strain rate, etc). The Kolsky bars used for dynamic structural characterization are briefly introduced. A collection of dynamic properties of various materials under various testing conditions is included which may serve as a reference database. This book assists both beginners and experienced professionals in characterizing high-rate material response with high quality and consistency. Readers who may benefit from this work include university students, instructors, R & D professionals, and scholars/engineers in solid mechanics, aerospace, civil and mechanical engineering, as well as materials science and engineering.

Download or read book Guide to Load Analysis for Durability in Vehicle Engineering written by P. Johannesson and published by John Wiley & Sons. This book was released on 2013-08-29 with total page 469 pages. Available in PDF, EPUB and Kindle. Book excerpt: The overall goal of vehicle design is to make a robust and reliable product that meets the demands of the customers and this book treats the topic of analysing and describing customer loads with respect to durability. Guide to Load Analysis for Vehicle and Durability Engineering supplies a variety of methods for load analysis and also explains their proper use in view of the vehicle design process. In Part I, Overview, there are two chapters presenting the scope of the book as well as providing an introduction to the subject. Part II, Methods for Load Analysis, describes useful methods and indicates how and when they should be used. Part III, Load Analysis in view of the Vehicle Design Process, offers strategies for the evaluation of customer loads, in particular characterization of customer populations, which leads to the derivation of design loads, and finally to the verification of systems and components. Key features: • Is a comprehensive collection of methods for load analysis, vehicle dynamics and statistics • Combines standard load data analysis methods with statistical aspects on deriving test loads from surveys of customer usage • Sets the methods used in the framework of system dynamics and response, and derives recommendations for the application of methods in engineering practice • Presents a reliability design methodology based on statistical evaluation of component strength and customers loads • Includes case studies and illustrative examples that translate the theory into engineering practice Developed in cooperation with six European truck manufacturers (DAF, Daimler, Iveco, MAN, Scania and Volvo) to meet the needs of industry, Guide to Load Analysis for Vehicle and Durability Engineering provides an understanding of the current methods in load analysis and will inspire the incorporation of new techniques in the design and test processes.

Download or read book Government Reports Announcements Index written by and published by . This book was released on 1984-08 with total page 924 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Publications of the National Bureau of Standards written by United States. National Bureau of Standards and published by . This book was released on 1974 with total page 544 pages. Available in PDF, EPUB and Kindle. Book excerpt: