Academic literature on the topic 'Dynamic wheel loads'
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Journal articles on the topic "Dynamic wheel loads"
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He, Zhihang, Wei Wang, Huaping Ruan, Yanzhang Yao, Xuelong Li, Dehua Zou, Yu Yan, and Shaochun Jia. "A two-wheel load balance control strategy for an HVTL inspection robot based on second-order sliding-mode." Industrial Robot: the international journal of robotics research and application 46, no. 1 (January 21, 2019): 83–92. http://dx.doi.org/10.1108/ir-10-2018-0212.
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Purpose Overhead high-voltage transmission line (HVTL) inspection robots are used to inspect the transmission lines and/or maintain the infrastructures of a power transmission grid. One of the most serious problems is that the load on the front wheel is much larger than that on the back one when the robot travels along a sloping earth wire. Thus, ongoing operation of the inspection robot mainly depends on the front wheel motor’s ability. This paper aims to extend continuous operation time of the HVTL inspection robots. Design/methodology/approach By introducing a traction force model, the authors have established a dynamic model of the robot with slip. The total load is evenly distributed to both wheels. According to the traction force model, the desired wheel slip is calculated to achieve the goal of load balance. A wheel slip controller was designed based on second-order sliding-mode control methodology. Findings This controller accomplishes the control objective, such that the actual wheel slip tracks the desired wheel slip. A simulation and experiment verify the feasibility of the load balance control system. These results indicate that the loads on both wheels are generally equal. Originality/value By balancing the loads on both wheels, the inspection robot can travel along the earth wire longer, improving its efficiency.
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O'Connor, Colin, and Tommy Hung Tin Chan. "Dynamic Wheel Loads From Bridge Strains." Journal of Structural Engineering 114, no. 8 (September 1988): 1703–23. http://dx.doi.org/10.1061/(asce)0733-9445(1988)114:8(1703).
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Kim, Sang-Hyo, Kwang-Il Cho, Moon-Seock Choi, and Ji-Young Lim. "Development of a Generation Method of Artificial Vehicle Wheel Load to Analyze Dynamic Behavior of Bridges." Advances in Structural Engineering 12, no. 4 (August 2009): 479–501. http://dx.doi.org/10.1260/136943309789508474.
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In this study, artificial wheel loads are proposed which reflect the dynamic effects of running vehicles and road roughness to overcome shortcomings of vehicle modeling methods. To derive a suitable artificial load from the moving vehicle model, a parametric study is conducted regarding span lengths, types of bridges, road roughnesses, vehicle speeds and consecutive vehicles. After that, Power Spectral Density (PSD) analyses of wheel loads are performed using Maximum Entropy Method (MEM). Based on the result, a representative PSD function is proposed considering the cumulative energy distribution and the area of the PSD curve. The artificial wheel loads are generated based on this PSD function. Also, dynamic analyses of a bridge are performed using the artificial wheel loads. The probabilistic characteristics of dynamic responses are evaluated by comparing the results with the existing moving vehicle model. The results show that the dynamic responses through the proposed method are slightly overestimated. It is concluded that the proposed method is a simple and reliable procedure for engineers to perform a dynamic analysis in practical design.
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Dolipski, Marian, Eryk Remiorz, and Piotr Sobota. "Determination of Dynamic Loads of Sprocket Drum Teeth and Seats by Means of a Mathematical Model of the Longwall Conveyor / Wyznaczenie Obciążeń Dynamicznych Zębów I Gniazd Bębna Łańcuchowego Za Pomocą Modelu Matematycznego Przenośnika Ścianowego." Archives of Mining Sciences 57, no. 4 (December 1, 2012): 1101–19. http://dx.doi.org/10.2478/v10267-012-0073-7.
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Abstract Scraper conveyors are one of the key machines forming part of mechanised longwall systems. They are currently the only means of transporting the mined rock from longwalls in hard coal mines. The hauling force caused by the drive is transmitted onto a link chain through drive wheels with their external shape corresponding to a geometric polygon. The number of teeth (seats) in such wheels ranges between 5 and 8. The horizontal links running on the drum are arranged in the drive wheel seats and are meshing with the teeth segments. The geometric relationships between the sprocket drum and the links are decisive for the position of the chain links in the seats. The abrasive wear of the chain parts and of the drive drum parts occurring due to conveyor operation is increasing the chain pitch and decreasing the wheel pitch. The position of a link in the seats changes as a result along with the load on the sprocket drum teeth and seats. Sprocket drums are the weakest element in longwall conveyors. It is, therefore, urgently necessary to determine the dynamic loads of such drums’ teeth and seats. The article presents a physical model and a mathematical model of a longwall conveyor created for the purpose of determination of dynamic loads of the sprocket drum teeth and seats. The results of computer simulations are also presented (dynamic loads: in chains, dynamic loads of sprocket drums and dynamic loads of sprocket drums’ teeth and seats) carried out using the created mathematical model for a 350 m long face conveyor.
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Nallusamy, S., N. Manikanda Prabu, K. Balakannan, and Gautam Majumdar. "Analysis of Static Stress in an Alloy Wheel of the Passengercar." International Journal of Engineering Research in Africa 16 (June 2015): 17–25. http://dx.doi.org/10.4028/www.scientific.net/jera.16.17.
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The vehicle may be towed without the engine but it is not possible without the wheels. Road wheel is a significant structural member of the vehicular suspension system that supports the static and dynamic loads encountered during vehicle operation. As in the case of an automobile wheel maximum load is applied on the alloy wheel. Proper analysis of the alloy wheel plays a significant role for the safety of the passenger cars. Alloy wheels which are intended for normal use on passenger cars, undergo three tests and have to pass before going into the production: Dynamic Cornering Fatigue Test, Dynamic Radial Fatigue Test and Impact Test. Most of aluminium alloy wheels manufacturing companies have done several testing of their product however information of their method on simulation test is often kept limited. During a part of research a static and fatigue analysis of aluminum alloy wheel A356.0 was carried out using FEA package. The 3-D model was imported from CATIA into ANSYS using the appropriate format. Finite element analysis (FEA) is carried out by simulating the test conditions to analyze stress distribution and fatigue life of the aluminium alloy wheel rim of passenger car. Experimental analyses are carried out by radial fatigue testing machine for evaluation of fatigue life under influence of camber angle. The test indicates that integrating FEA and nominal stress method is a good and efficient method to predict alloy wheels fatigue life. In this paper by observing the results of both static and dynamic analysis the aluminium alloy is suggested as better material.
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Husaini, Ali Nurdin, Abdillah Sofian, and Nuzan Rizki Muhammad. "Comparison of Hardness and Microstructure of Cast Wheel and Spoke Wheel Rims of Motorcycles Made of Aluminum Alloy Alloy." Key Engineering Materials 892 (July 13, 2021): 81–88. http://dx.doi.org/10.4028/www.scientific.net/kem.892.81.
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The rim is one of the main components in a motorized vehicle system, both two and three wheels. Rim loads when used are dynamic and often even shock. This study aims to study the mechanical characteristics, especially the hardness properties of spoke wheel rims and cast wheel rims made of aluminum alloy used in motorcycles and compare the results. Hardness testing is carried out on the spoke wheel and cast wheel specimens, using the Rockwell method with an identifier of 1/16 ball and a spectrometer used for both microstructure observations. The result of the average hardness test for the spoke wheel is HRB 99.3, while for the cast wheel is HRB 76.5. From the hardness test, it can be concluded that the hardness of the spoke wheel type is higher than the cast wheel type due to the difference in the manufacturing process. Cast wheel rims can withstand a load of 3 tons (30000 N) and the value of rim tension that can be accepted until the fracture is 45.84 MPa. Meanwhile, spoke wheel rims have the ability to withstand smaller compressive loads than cast wheel rims, which are 2 tonnes (20000 N) and the rims can accept the stress of 66.04 MPa until they break.
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Vale, Cecilia. "Wheel Flats in the Dynamic Behavior of Ballasted and Slab Railway Tracks." Applied Sciences 11, no. 15 (August 2, 2021): 7127. http://dx.doi.org/10.3390/app11157127.
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Wheel flats induce high-impact loads with relevance for the safety of the vehicle in operation as they can contribute to broken axles, hot axle boxes, and damaged rolling bearings and wheels. The high loads also induce damage in the track components such as rails and sleepers. Although this subject has been studied numerically and experimentally over the last few years, the wheel flat problem has focused on ballasted tracks, and there is a need to understand the phenomena also for slab tracks. In this research, a numerical approach was used to show the effects of the wheel flats with different geometric configurations on the dynamic behavior of a classical ballasted track and a continuous slab track. Several wheel flat geometries and different vehicle speeds were considered. The nonlinear Hertzian contact model was used because of the high dynamic variation of the interaction of the load between the vehicle and the rail. The results evidenced that, for the same traffic conditions, the dynamic force was higher on the slab track than on the ballasted one, contrary to the maximum vertical displacement, which was higher on the ballasted track due to the track differences regarding the stiffness and frequency response. The results are useful for railway managers who wish to monitor track deterioration under the regulatory limits.
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Sadeghi, J. M. "Experimental evaluation of accuracy of current practices in analysis and design of railway track sleepers." Canadian Journal of Civil Engineering 35, no. 9 (September 2008): 881–93. http://dx.doi.org/10.1139/l08-026.
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This research investigates the accuracy of the assumptions made in the current method of analysis and design of railway track sleepers. This study consists of a comprehensive field investigation into the response of sleepers in a railway track system to static and dynamic loads. In the experiments, several load cells (load gauges) are installed under a rail seat and beneath a B70 concrete sleeper for the purpose of monitoring the response of the sleeper to vertical loads. The dynamic coefficients factor, the ratio of the rail seat load to the wheel load and the pressures between the sleeper and the ballast are measured. The results are used to evaluate the current approaches for the analysis and design of concrete sleepers, in particular those proposed by the Americans (AREMA) and Europeans (UIC). New models are proposed for the calculation of dynamic load factors, correlations between wheel loads and rail seat loads, and load distribution patterns beneath sleepers.
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Zolotarevskaya, D. I. "Analysis of the influence of the main factors on the characteristics of the elastic properties of elastic wheels of tractors." Traktory i sel hozmashiny 85, no. 4 (August 15, 2018): 71–78. http://dx.doi.org/10.17816/0321-4443-66415.
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The work is devoted to the theoretical study of the elastic properties of tractor wheels and the analysis of the effect of air pressure in the tires and vertical loads on the wheel axles. According to the developed computer program, which allows to implement the method of calculating the characteristics of the elastic properties of tractor wheels with pneumatic tires proposed in this work, one-factor and complete factor computer experiments of two types were carried out. In computer experiments of the first type, the dependences of the elasticity coefficients of a number of elastic wheels were investigated when operating on the practically non-deformable basis of tractors MTZ-82 and MTZ-142 from the air pressure in the tires at different values of the vertical dynamic loads on the axes of the corresponding wheels of tractors. In computer experiments of the second type, the dependences of the elasticity coefficients and the normal deflection of the wheels with tires of different sizes from the air pressure in the tires at constant values of the vertical dynamic loads on the wheel axles were investigated. In computer experiments of both types, the deviations of the elastic properties of elastic wheels found by calculation are within the limits of the accuracy of measurements of the experimental data. Based on the results of computer experiments of the first type, regression equations were obtained reflecting the dependence of the elasticity coefficients of the elastic wheels studied on the air pressure in the tire for various values of the vertical dynamic loads on the wheel axes. According to the results of computer experiments of the second type, equations of regression of the coefficients of elasticity and normal deflection of wheels with tires of different sizes from air pressure in tires at constant values of vertical dynamic loads on the wheel axle are obtained. The high correlation values for these regression equations indicate the high importance of the relationships in the found correlation dependencies. The application of the proposed calculation method makes it possible to simplify and shorten the work on the choice of tires of optimum sizes to different tractors, taking into account the specific conditions of their operation. It was calculated that wheels with tires 18.4R38 are optimal on the rear axle of the MTZ-82 tractor.
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Savinkin, Vitaliy V., Zaure Zh Zhumekenova, Andrei Victor Sandu, Petrica Vizureanu, Sergey V. Savinkin, Sergey N. Kolisnichenko, and Olga V. Ivanova. "Study of Wear and Redistribution Dynamic Forces of Wheel Pairs Restored by a Wear-Resistant Coating 15Cr17Ni12V3F." Coatings 11, no. 12 (November 24, 2021): 1441. http://dx.doi.org/10.3390/coatings11121441.
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The relevance of this study lies in the need to research the wear process of the elements of dynamic systems and to establish the dependence of the geometric and structural characteristics of wheels restored by plasma surfacing with a coating of 15Cr17Ni12V3F on dynamic, cyclically varying loads. The study was aimed to establish the dependencies between the deviation of the wear area, the formation of contact and fatigue stresses, and the change in the phase structure of the wheel defect. It is important to justify the permissible limits of wear of the transverse profile in the contact zone of a wheel and ridge. The object of the study was the dynamic interaction of the “wheel–ridge–rail contact surface” system. To achieve the goal, the following methodology was adopted: kinematic analysis, strength calculation, the use of mathematical analysis in dynamic system modelling, virtual modelling in the SOLIDWORKS software environment of the GearTrax application, experiment planning, and model correction through the results of metallographic studies. The results of the study are presented as reasonable prediction criteria that consider contact cycles during the formation of fatigue stresses at the stage of defect origin. The process of the dynamic interaction of the contact worn profile of a wheel with a railway rail is explored. Polynomial equations are proposed to substantiate the optimal design and technological parameters of designing a railway carriage wheel. The permissible limits of wear of the transverse profile in the contact zone of the wheel and the ridge are justified while taking the coefficient of the reduction of contact stresses in the metal into account. The dependences of the change in static load on the utilization factor of the railway carriage load capacity are established. The dependences of changes in fatigue stresses on the design deviation of the contact area of wheel wear are established. It is confirmed that the stress concentration under cyclic loads is formed in the ferritic layers of the material structure before the appearance of wear.
Dissertations / Theses on the topic "Dynamic wheel loads"
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Siddiqui, Owais Mustafa. "Dynamic analysis of a modern urban bus for assessment of ride quality and dynamic wheel loads." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape4/PQDD_0018/MQ54328.pdf.
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Smagina, Zana. "Dynamic amplification for moving vehicle loads on buried pipes : Evaluation of field-tests." Thesis, KTH, Bro- och stålbyggnad, 2001. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-36801.
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Hosseini, SayedMohammad. "A Statistical Approach to Modeling Wheel-Rail Contact Dynamics." Thesis, Virginia Tech, 2021. http://hdl.handle.net/10919/101864.
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The wheel-rail contact mechanics and dynamics that are of great importance to the railroad industry are evaluated by applying statistical methods to the large volume of data that is collected on the VT-FRA state-of-the-art roller rig. The intent is to use the statistical principles to highlight the relative importance of various factors that exist in practice to longitudinal and lateral tractions and to develop parametric models that can be used for predicting traction in conditions beyond those tested on the rig. The experiment-based models are intended to be an alternative to the classical traction-creepage models that have been available for decades. Various experiments are conducted in different settings on the VT-FRA Roller Rig at the Center for Vehicle Systems and Safety at Virginia Tech to study the relationship between the traction forces and the wheel-rail contact variables. The experimental data is used to entertain parametric and non-parametric statistical models that efficiently capture this relationship. The study starts with single regression models and investigates the main effects of wheel load, creepage, and the angle of attack on the longitudinal and lateral traction forces. The assumptions of the classical linear regression model are carefully assessed and, in the case of non-linearities, different transformations are applied to the explanatory variables to find the closest functional form that captures the relationship between the response and the explanatory variables. The analysis is then extended to multiple models in which interaction among the explanatory variables is evaluated using model selection approaches. The developed models are then compared with their non-parametric counterparts, such as support vector regression, in terms of "goodness of fit," out-of-sample performance, and the distribution of predictions.Master of Science
The interaction between the wheel and rail plays an important role in the dynamic behavior of railway vehicles. The wheel-rail contact has been extensively studied through analytical models, and measuring the contact forces is among the most important outcomes of such models. However, these models typically fall short when it comes to addressing the practical problems at hand. With the development of a high-precision test rig—called the VT-FRA Roller Rig, at the Center for Vehicle Systems and Safety (CVeSS)—there is an increased opportunity to tackle the same problems from an entirely different perspective, i.e. through statistical modeling of experimental data. Various experiments are conducted in different settings that represent railroad operating conditions on the VT-FRA Roller Rig, in order to study the relationship between wheel-rail traction and the variables affecting such forces. The experimental data is used to develop parametric and non-parametric statistical models that efficiently capture this relationship. The study starts with single regression models and investigates the main effects of wheel load, creepage, and the angle of attack on the longitudinal and lateral traction forces. The analysis is then extended to multiple models, and the existence of interactions among the explanatory variables is examined using model selection approaches. The developed models are then compared with their non-parametric counterparts, such as support vector regression, in terms of "goodness of fit," out-of-sample performance, and the distribution of the predictions. The study develops regression models that are able to accurately explain the relationship between traction forces, wheel load, creepage, and the angle of attack.
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Cummings, Patrick. "Modeling the Locked-Wheel Skid Tester to Determine the Effect of Pavement Roughness on the International Friction Index." Scholar Commons, 2010. https://scholarcommons.usf.edu/etd/1604.
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Pavement roughness has been found to have an effect on the coefficient of friction measured with the Locked-Wheel Skid Tester (LWT) with measured friction decreasing as the long wave roughness of the pavement increases. However, the current pavement friction standardization model adopted by the American Society for Testing and Materials (ASTM), to compute the International Friction Index (IFI), does not account for this effect. In other words, it had been previously assumed that the IFI's speed constant (SP), which defines the gradient of the pavement friction versus speed relationship, is an invariant for any pavement with a given mean profile depth (MPD), regardless of its roughness. This study was conducted to quantify the effect of pavement roughness on the IFI's speed constant. The first phase of this study consisted of theoretical modeling of the LWT using a two-degree of freedom vibration system. The model parameters were calibrated to match the measured natural frequencies of the LWT. The calibrated model was able to predict the normal load variation during actual LWT tests to a reasonable accuracy. Furthermore, by assuming a previously developed skid number (SN) versus normal load relationship, even the friction profile of the LWT during an actual test was predicted reasonably accurately. Because the skid number (SN) versus normal load relationship had been developed previously using rigorous protocol, a new method that is more practical and convenient was prescribed in this work. This study concluded that higher pavement long-wave roughness decreases the value of the SP compared to a pavement with identical MPD but lower roughness. Finally, the magnitude of the loss of friction was found to be governed by the non-linear skid number versus normal load characteristics of a pavement.
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Kassner, Bernard Leonard. "Long-term In-service Evaluation of Two Bridges Designed with Fiber-Reinforced Polymer Girders." Thesis, Virginia Tech, 2004. http://hdl.handle.net/10919/10122.
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A group of researchers, engineers, and government transportation officials have teamed up to design two bridges with simply-supported FRP composite structural beams. The Toms Creek Bridge, located in Blacksburg, Virginia, has been in service for six years. Meanwhile, the Route 601 Bridge, located in Sugar Grove, Virginia, has been in service for two years.
Researchers have conducted load tests at both bridges to determine if their performance has changed during their respective service lives. The key design parameters under consideration are: deflection, wheel load distribution, and dynamic load allowance.
The results from the latest tests in 2003 yield little, yet statistically significant, changes in these key factors for both bridges. Most differences appear to be largely temperature related, although the reason behind this effect is unclear. For the Toms Creek Bridge, the largest average values from the 2003 tests are 440 me for service strain, 0.43 in. (L/484) for service deflection, 0.08 (S/11.1) for wheel load distribution, and 0.64 for dynamic load allowance. The values for the Route 601 Bridge are 220 me, 0.38 in. (L/1230), 0.34 (S/10.2), and 0.14 for the same corresponding paramters.
The recommended design values for the dynamic load allowance in both bridges have been revised upwards to 1.35 and 0.50 for the Toms Creek Bridge and Route 601 Bridge, respectively, to account for variability in the data. With these increased factors, the largest strain in the toms Creek Bridge and Route 601 Bridge would be less than 13% and 12%, respectively, of ultimate strain. Therefore, the two bridges continue to provide a large factor of safety against failure.Master of Science
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Collins, William Norfleet. "Live Load Testing and Analysis of the Southbound Span of U.S. Route 15 over Interstate-66." Thesis, Virginia Tech, 2010. http://hdl.handle.net/10919/34364.
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As aging bridges around the United States begin to near the end of their service lives,
more funding must be allocated for their rehabilitation or replacement. The Federal Highway
Administrationâ s (FHWA) Long-Term Bridge Performance (LTBP) Program has been developed
to help bridge stakeholders make the best decisions concerning the allocation of these funds.
This is done through the use of high quality data obtained through numerous testing processes.
As part of the LTBP Pilot Program, researchers have performed live load tests on the
U.S. Route 15 Southbound bridge over Interstate-66. The main performance and behavior
characteristics focused on are service strain and deflection, wheel load distribution, dynamic load
allowance, and rotational behavior of bridge bearings.
Data from this test will be used as a tool in developing and refining a plan for long-term
bridge monitoring. This includes identifying the primarily loaded girders and their expected
range of response under ambient traffic conditions. Information obtained from this test will also
aid in the refinement of finite element models by offering insight into the performance of
individual bridge components, as well as overall global behavior. Finally, the methods and
results of this test have been documented to allow for comparison with future testing of this
bridge, which will yield information concerning the changes in bridge behavior over time.Master of Science
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Neely, William Douglas. "Evaluation of the In-Servic Performance of the Tom's Creek Bridge." Thesis, Virginia Tech, 2000. http://hdl.handle.net/10919/33249.
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The Tom's Creek Bridge is a small-scale demonstration project involving the use of fiber-reinforced polymer (FRP) composite girders as the main load carrying members. The project is intended to serve two purposes. First, by calculating bridge design parameters such as the dynamic load allowance, transverse wheel load distribution and deflections under service loading, the Tom's Creek Bridge will aid in modifying current AASHTO bridge design standards for use with FRP composite materials. Second, by evaluating the FRP girders after being exposed to service conditions, the project will begin to answer questions about the long-term performance of these advanced composite material beams when used in bridge design.
This thesis details the In-Service analysis of the Tom's Creek Bridge. Five load tests, at six month intervals, were conducted on the bridge. Using mid-span strain and deflection data gathered from the FRP composite girders during these tests the above mentioned bridge design parameters have been determined. The Tom's Creek Bridge was determined to have a dynamic load allowance, IM, of 0.90, a transverse wheel load distribution factor, g, of 0.101 and a maximum deflection of L/488.
Two bridge girders were removed from the Tom's Creek Bridge after fifteen months of service loading. These FRP composite girders were tested at the Structures and Materials Research Laboratory at Virginia Tech for stiffness and ultimate strength and compared to pre-service values for the same beams. This analysis indicates that after fifteen months of service, the FRP composite girders have not lost a significant amount of either stiffness or ultimate strength.Master of Science
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Restrepo, Edgar Salom. "Determination of AASHTO Bridge Design Parameters through Field Evaluation of the Rt. 601 Bridge: A Bridge Utilizing Strongwell 36 in. Fiber-Reinforced Polymer Double Web Beams as the Main Load Carrying Members." Thesis, Virginia Tech, 2002. http://hdl.handle.net/10919/36182.
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The Route 601 Bridge in Sugar Grove, Virginia spans 39 ft over Dickey Creek. The Bridge is the first to use the Strongwell 36 in. fiber reinforced polymer (FRP) double web beam (DWB) in its superstructure. Replacement of the old bridge began in June 2001, and construction of the new bridge was completed in October 2001. The bridge was field tested in October 2001 and June 2002.
This thesis details the field evaluation of the Rt. 601 Bridge. Using mid span deflection and strain data from the October 2001 and June 2002 field tests, the primary goal of this research was to determine the following AASHTO bridge design parameters: wheel load distribution factor g, dynamic load allowance IM, and maximum deflection. The wheel load distribution factor was determined to be S/5, a dynamic load allowance was determined to be 0.30, and the maximum deflection of the bridge was L/1500. Deflection results were lower than the AASHTO L/800 limit. This discrepancy is attributed to partial composite action of the deck-to-girder connections, bearing restraint at the supports, and contribution of guardrail stiffness.
Secondary goals of this research were to quantify the effect of diaphragm removal on girder distribution factor, determine torsion and axial effects of the FRP girders, compare responses to multiple lane symmetrical loading to superimposed single lane response, and compare the field test results to a finite element and a finite difference model. It was found that diaphragm removal had a small effect on the wheel load distribution factor. Torsional and axial effects were small. The bridge response to multilane loading coincided with superimposed single lane truck passes, and curb-stiffening effects in a finite difference model improved the accuracy of modeling the Rt. 601 Bridge behavior.Master of Science
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Bian, Jian. "Ultimate flexural limit states analysis of prestressed concrete sleeper." Thesis, Queensland University of Technology, 2012. https://eprints.qut.edu.au/63660/1/Jian_Bian_Thesis.pdf.
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Railway is one of the most important, reliable and widely used means of transportation, carrying freight, passengers, minerals, grains, etc. Thus, research on railway tracks is extremely important for the development of railway engineering and technologies. The safe operation of a railway track is based on the railway track structure that includes rails, fasteners, pads, sleepers, ballast, subballast and formation. Sleepers are very important components of the entire structure and may be made of timber, concrete, steel or synthetic materials. Concrete sleepers were first installed around the middle of last century and currently are installed in great numbers around the world. Consequently, the design of concrete sleepers has a direct impact on the safe operation of railways.
The "permissible stress" method is currently most commonly used to design sleepers. However, the permissible stress principle does not consider the ultimate strength of materials, probabilities of actual loads, and the risks associated with failure, all of which could lead to the conclusion of cost-ineffectiveness and over design of current prestressed concrete sleepers. Recently the limit states design method, which appeared in the last century and has been already applied in the design of buildings, bridges, etc, is proposed as a better method for the design of prestressed concrete sleepers. The limit states design has significant advantages compared to the permissible stress design, such as the utilisation of the full strength of the member, and a rational analysis of the probabilities related to sleeper strength and applied loads.
This research aims to apply the ultimate limit states design to the prestressed concrete sleeper, namely to obtain the load factors of both static and dynamic loads for the ultimate limit states design equations. However, the sleepers in rail tracks require different safety levels for different types of tracks, which mean the different types of tracks have different load factors of limit states design equations. Therefore, the core tasks of this research are to find the load factors of the static component and dynamic component of loads on track and the strength reduction factor of the sleeper bending strength for the ultimate limit states design equations for four main types of tracks, i.e., heavy haul, freight, medium speed passenger and high speed passenger tracks.
To find those factors, the multiple samples of static loads, dynamic loads and their distributions are needed. In the four types of tracks, the heavy haul track has the measured data from Braeside Line (A heavy haul line in Central Queensland), and the distributions of both static and dynamic loads can be found from these data. The other three types of tracks have no measured data from sites and the experimental data are hardly available. In order to generate the data samples and obtain their distributions, the computer based simulations were employed and assumed the wheel-track impacts as induced by different sizes of wheel flats. A valid simulation package named DTrack was firstly employed to generate the dynamic loads for the freight and medium speed passenger tracks. However, DTrack is only valid for the tracks which carry low or medium speed vehicles. Therefore, a 3-D finite element (FE) model was then established for the wheel-track impact analysis of the high speed track. This FE model has been validated by comparing its simulation results with the DTrack simulation results, and with the results from traditional theoretical calculations based on the case of heavy haul track. Furthermore, the dynamic load data of the high speed track were obtained from the FE model and the distributions of both static and dynamic loads were extracted accordingly. All derived distributions of loads were fitted by appropriate functions. Through extrapolating those distributions, the important parameters of distributions for the static load induced sleeper bending moment and the extreme wheel-rail impact force induced sleeper dynamic bending moments and finally, the load factors, were obtained. Eventually, the load factors were obtained by the limit states design calibration based on reliability analyses with the derived distributions. After that, a sensitivity analysis was performed and the reliability of the achieved limit states design equations was confirmed. It has been found that the limit states design can be effectively applied to railway concrete sleepers.
This research significantly contributes to railway engineering and the track safety area. It helps to decrease the failure and risks of track structure and accidents; better determines the load range for existing sleepers in track; better rates the strength of concrete sleepers to support bigger impact and loads on railway track; increases the reliability of the concrete sleepers and hugely saves investments on railway industries.
Based on this research, many other bodies of research can be promoted in the future. Firstly, it has been found that the 3-D FE model is suitable for the study of track loadings and track structure vibrations. Secondly, the equations for serviceability and damageability limit states can be developed based on the concepts of limit states design equations of concrete sleepers obtained in this research, which are for the ultimate limit states.
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Davis, Lloyd Eric. "Heavy vehicle suspensions : testing and analysis." Thesis, Queensland University of Technology, 2010. https://eprints.qut.edu.au/34499/1/Lloyd_Davis_Thesis.pdf.
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Transport regulators consider that, with respect to pavement damage, heavy vehicles (HVs) are the riskiest vehicles on the road network. That HV suspension design contributes to road and bridge damage has been recognised for some decades. This thesis deals with some aspects of HV suspension characteristics, particularly (but not exclusively) air suspensions. This is in the areas of developing low-cost in-service heavy vehicle (HV) suspension testing, the effects of larger-than-industry-standard longitudinal air lines and the characteristics of on-board mass (OBM) systems for HVs. All these areas, whilst seemingly disparate, seek to inform the management of HVs, reduce of their impact on the network asset and/or provide a measurement mechanism for worn HV suspensions. A number of project management groups at the State and National level in Australia have been, and will be, presented with the results of the project that resulted in this thesis. This should serve to inform their activities applicable to this research. A number of HVs were tested for various characteristics. These tests were used to form a number of conclusions about HV suspension behaviours. Wheel forces from road test data were analysed. A “novel roughness” measure was developed and applied to the road test data to determine dynamic load sharing, amongst other research outcomes. Further, it was proposed that this approach could inform future development of pavement models incorporating roughness and peak wheel forces. Left/right variations in wheel forces and wheel force variations for different speeds were also presented. This led on to some conclusions regarding suspension and wheel force frequencies, their transmission to the pavement and repetitive wheel loads in the spatial domain. An improved method of determining dynamic load sharing was developed and presented. It used the correlation coefficient between two elements of a HV to determine dynamic load sharing. This was validated against a mature dynamic loadsharing metric, the dynamic load sharing coefficient (de Pont, 1997). This was the first time that the technique of measuring correlation between elements on a HV has been used for a test case vs. a control case for two different sized air lines. That dynamic load sharing was improved at the air springs was shown for the test case of the large longitudinal air lines. The statistically significant improvement in dynamic load sharing at the air springs from larger longitudinal air lines varied from approximately 30 percent to 80 percent. Dynamic load sharing at the wheels was improved only for low air line flow events for the test case of larger longitudinal air lines. Statistically significant improvements to some suspension metrics across the range of test speeds and “novel roughness” values were evident from the use of larger longitudinal air lines, but these were not uniform. Of note were improvements to suspension metrics involving peak dynamic forces ranging from below the error margin to approximately 24 percent. Abstract models of HV suspensions were developed from the results of some of the tests. Those models were used to propose further development of, and future directions of research into, further gains in HV dynamic load sharing. This was from alterations to currently available damping characteristics combined with implementation of large longitudinal air lines. In-service testing of HV suspensions was found to be possible within a documented range from below the error margin to an error of approximately 16 percent. These results were in comparison with either the manufacturer’s certified data or test results replicating the Australian standard for “road-friendly” HV suspensions, Vehicle Standards Bulletin 11. OBM accuracy testing and development of tamper evidence from OBM data were detailed for over 2000 individual data points across twelve test and control OBM systems from eight suppliers installed on eleven HVs. The results indicated that 95 percent of contemporary OBM systems available in Australia are accurate to +/- 500 kg. The total variation in OBM linearity, after three outliers in the data were removed, was 0.5 percent. A tamper indicator and other OBM metrics that could be used by jurisdictions to determine tamper events were developed and documented. That OBM systems could be used as one vector for in-service testing of HV suspensions was one of a number of synergies between the seemingly disparate streams of this project.
Books on the topic "Dynamic wheel loads"
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Roeder, C. W. Field measurements of dynamic wheel loads on modular expansion joints. [Olympia, Wash.]: Washington State Dept. of Transportation, 1995.
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Kelly, Carney, Gallardo V. C, and NASA Glenn Research Center, eds. A study of fan stage/casing interaction models. Cleveland, Ohio: National Aeronautics and Space Administration, Glenn Research Center, 2003.
Find full textBook chapters on the topic "Dynamic wheel loads"
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Blanksby, C., R. George, B. Peters, A. Ritzinger, and L. Bruzsa. "Measuring dynamic wheel loads on tri and quad axle groups." In International Conference on Heavy Vehicles HVParis 2008, 223–36. Hoboken, NJ, USA: John Wiley & Sons, Inc, 2013. http://dx.doi.org/10.1002/9781118623305.ch17.
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Gorbunov, Nikolai, Gintautas Bureika, Maksim Kovtanets, Gediminas Vaičiūnas, Olga Prosvirova, and Oksana Sergienko. "Study of Dynamic Loads in the Wheel and Rail Contact Influence on the Maximum Adhesion Coefficient." In TRANSBALTICA XI: Transportation Science and Technology, 235–44. Cham: Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-030-38666-5_25.
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Brötz, Nicolas, Manuel Rexer, and Peter F. Pelz. "Mastering Model Uncertainty by Transfer from Virtual to Real System." In Lecture Notes in Mechanical Engineering, 35–44. Cham: Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-77256-7_4.
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AbstractTwo chassis components were developed at the Technische Universität Darmstadt that are used to isolate the body and to reduce wheel load fluctuation.The frequency responses of the components were identified with a stochastic foot point excitation in a hardware-in-the-loop (HiL) simulation environment at the hydropulser. The modelling of the transmission behaviour influence of the testing machine on the frequency response was approximately represented with a time delay of $$10\,\mathrm {ms}$$ 10 ms in the frequency range up to $$25\,\mathrm {Hz}$$ 25 Hz . This is considered by a Padé approximation. It can be seen that the dynamics of the testing machine have an influence on the wheel load fluctuation and the body acceleration, especially in the natural frequency of the unsprung mass. Therefor, the HiL stability is analysed by mapping the poles of the system in the complex plane, influenced by the time delay and virtual damping.This paper presents the transfer from virtual to real quarter car to quantify the model uncertainty of the component, since the time delay impact does not occur in the real quarter car test rig. The base point excitation directly is provided by the testing machine and not like in the case of the HiL test rig, the compression of the spring damper calculated in the real-time simulation.
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Ahlbeck, Donald R. "A Study of Dynamic Impact Load Effects Due to Railroad Wheel Profile Roughness." In The Dynamics of Vehicles on roads and on tracks, 13–16. London: CRC Press, 2021. http://dx.doi.org/10.1201/9781003210894-2.
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Demiyanushko, Irina, Aleksandr Vakhromeev, Evgeny Loginov, and Violetta Mironova. "The Dynamic Behavior of the Vehicle Wheels Under Impact Loads—FEM and Experimental Researches." In Springer Proceedings in Mathematics & Statistics, 125–34. Cham: Springer International Publishing, 2018. http://dx.doi.org/10.1007/978-3-319-96598-7_11.
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Long, Le Xuan, Dang Viet Ha, Nguyen Van Tuan, Vu Thanh Niem, and Vu Thi Hien. "A Simulation Investigation of Dynamic Wheel Load of a Heavy Truck with Hydro-Pneumatic Suspension System." In Advances in Engineering Research and Application, 74–83. Cham: Springer International Publishing, 2022. http://dx.doi.org/10.1007/978-3-031-22200-9_8.
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Shankar, Sarath, Subodh Kumar Nirala, Saayan Banerjee, Dhanalakshmi Sathishkumar, and P. Sivakumar. "Delamination Growth Behaviour in Carbon/Epoxy Composite Road Wheel of an Armoured Fighting Vehicle Under Dynamic Load." In Lecture Notes in Mechanical Engineering, 429–41. Singapore: Springer Singapore, 2020. http://dx.doi.org/10.1007/978-981-15-5862-7_35.
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Sudheesh Kumar C P, Sujatha C, and Shankar K. "A Comparative Study of Two Different Wheel Load Models Used for the Estimation of Dynamic Responses of Bridges." In Advances in Transdisciplinary Engineering. IOS Press, 2022. http://dx.doi.org/10.3233/atde220795.
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Dynamic analysis of bridges under moving point loads is carried out in this paper. Two different wheel load models, model 1 with uniform space intervals and model 2 with non-uniform space intervals, in this study. Bridge responses due to single and multiple moving point loads are compared. Responses for both resonance and cancellation speeds are also estimated. Effects of damping, number of moving loads and their speed on the dynamic responses of the bridge using these two models are investigated. The objective is to make a comparative study of the two different wheel load models in terms of accuracy of the responses and computational easiness.
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P. Boronenko, Yuri, Rustam V. Rahimov, and Waail M. Lafta. "New Approach Measuring the Wheel/Rail Interaction Loads." In Railway Transport Planning and Management [Working Title]. IntechOpen, 2021. http://dx.doi.org/10.5772/intechopen.100031.
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This chapter suggested new methods for monitoring the dynamic processes of rolling stock/rail interaction. This study develops a new technical solution for measuring the wheel/rail interaction forces on a significant part of the sleeper. The theoretical part of this study, using FEM, confirm the ability of piecewise continuous recording of vertical and lateral forces from the wheel/rail interaction by measuring the stresses in two sections of the rail. Also, the optimum location of strain gauges and the effective length of the measuring zone have been determined. The experimental part of this study has been carried out on the stands and the railway track to confirm the effectiveness of the method to determine the vertical and lateral wheel/rail interaction forces, increase the reliable statistical data, improve the measurement accuracy, reducing the time and cost compared with current testing methods. The developed method is recommended to determine the wheel/rail interaction forces and identify defects on the wheels when diagnosing rolling stock on operational and travel regimes.
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"Effect of dynamic wheel loads on fatigue performance of RC slabs." In Reliability and Optimization of Structural Systems: Assessment, Design, and Life-Cycle Performance, 153–62. CRC Press, 2007. http://dx.doi.org/10.1201/b16819-15.
Full textConference papers on the topic "Dynamic wheel loads"
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Hu, Garrick. "Use of a Road Simulator for Measuring Dynamic Wheel Loads." In 1988 Conference and Exposition on Future Transportation Technology. 400 Commonwealth Drive, Warrendale, PA, United States: SAE International, 1988. http://dx.doi.org/10.4271/881194.
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Kim, Chul Woo, and Mitsuo Kawatani. "A Comparative Study on Dynamic Wheel Loads of Multi-Axle Vehicle and Bridge Responses." In ASME 2001 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference. American Society of Mechanical Engineers, 2001. http://dx.doi.org/10.1115/detc2001/vib-21526.
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Abstract To investigate relations between dynamic wheel loads of multi-axle vehicles on highway bridges and dynamic responses of bridge due to the vehicular loading, a three-dimensional dynamic analysis is carried out. Simultaneous differential equations for a coupling vibration of bridge and moving vehicle including roadway roughness are derived by means of modal analysis. The analytical wheel loads of vehicle model and responses of bridges are compared with experimental ones, to verify a validity of presented analytical procedure. Parametric investigations show that there exists resemblance between bounce motion of vehicle and bridge response. It can also be seen that the RMS based dynamic factor of dynamic wheel load can give an important information to predict the variation of impact factor of bridge due to speed condition as well as speed parameter.
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Van Dyk, Brandon J., Marcus S. Dersch, J. Riley Edwards, Conrad Ruppert, and Christopher P. L. Barkan. "Quantifying Shared Corridor Wheel Loading Variation Using Wheel Impact Load Detectors." In 2013 Joint Rail Conference. American Society of Mechanical Engineers, 2013. http://dx.doi.org/10.1115/jrc2013-2404.
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A sustained increase in heavy axle loads and cumulative freight tonnages, coupled with increased development of high speed passenger rail, is placing an increasing demand on railway infrastructure. Some of the most critical areas of the infrastructure in need of further research are track components used in high speed passenger, heavy haul, and shared infrastructure applications. In North America, many design guidelines for these systems use historical wheel loads that may not necessarily be representative of those seen on rail networks today. Without a clear understanding of the nature of these loads, it is impossible to adequately evaluate the superstructure to make design improvements. Therefore, researchers at the University of Illinois at Urbana-Champaign (UIUC) are conducting research to lay the groundwork for an improved and thorough understanding of the loading environment entering the track structure. Wheel impact load detectors (WILDs) have been used in North America for decades to identify bad-acting wheels that could damage the rail infrastructure or result in a rolling stock failure. The WILD measures vertical and lateral rail loads imparted by the wheel at the wheel-rail interface, along with other pertinent information related to the specific wheel, car, and train passing the instrumented site. This information can be used to identify and classify trends in the loading features and other characteristics of the rolling stock. These trends not only provide a clearer picture of the existing loading environment created by widely varied traffic characteristics, but can be used in future design and maintenance planning of infrastructure according to the anticipated traffic. This paper will discuss the current trends in wheel loads across the North American rail network while investigating the effects of speed on dynamic and impact loads. Ultimately this work should lead to useful distinctions of loads for improved design methodologies that are specific to the intended type of traffic traversing a given route or network.
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Ahmad, Husain, and Mehdi Ahmadian. "Model Reference Adaptive Control of Train Dynamic Braking." In 2012 Joint Rail Conference. American Society of Mechanical Engineers, 2012. http://dx.doi.org/10.1115/jrc2012-74141.
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Model Reference Adaptive Control (MRAC) is developed to control the amount of current through the traction motors under various wheel/rail adhesion conditions while braking. More accurate estimation and control of train braking distance will allow the trains to be run with closer spacing. In order to minimize the braking distance of a train, dynamic braking forces need to be maximized while maintaining good wheel/rail adhesion. Wheel/rail adhesion coefficient plays an important role in safe train braking. Excessively large dynamic braking can cause wheel lockup that can damage the wheels and the rail. In addition, it can cause large buff loads that cause derailment or coupler damage. Dynamic braking force is directly proportional to the current supplied to the traction motors. In this study, a multibody formulation of a locomotive and three railcars is used to develop a model reference adaptive controller for adjusting the current provided to the traction motors such that the maximum dynamic braking is achieved, without wheel lockup. Aerodynamic drag and air brake forces are included in the model. The coupler forces are also considered in the control model to ensure that they remain within acceptable levels. The results indicate that the MRAC system significantly improves braking distance while maintaining better wheel/rail adhesion and coupler dynamics during braking.
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Uzzal, Rajib Ul Alam, Subhash Rakheja, and Waiz Ahmed. "Dynamic Analysis of Pitch Plane Railway Vehicle-Track Interactions Due to Single and Multiple Wheel Flats." In IEEE/ASME/ASCE 2008 Joint Rail Conference. ASMEDC, 2008. http://dx.doi.org/10.1115/jrc2008-63023.
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The dynamic impact forces due to the wheel defect such as a flat is a main concern for a heavy freight train operating at high speed. The present investigation employs a pitch plane vehicle model coupled with a comprehensive three-layer track system model to study the impact force generated in the wheel-rail interface due to the presence of wheel flats. The wheel-rail contact is modeled using nonlinear Hertzian contact theory. Responses in terms of wheel-rail impact load and forces transmitted to bearings, pad and ballast are evaluated in an attempt to identify desirable design and operating factors. Wheel-rail impact loads due to the presence of multiple flats either in single or different wheels in-phase or out-of-phase conditions are evaluated and analyzed. A detailed parametric study is carried out that includes the variations in selected vehicle, track, operational as well as flat parameters. The results show that the effect of multiple flats is insignificant if they are more than 45° apart. The impact due to single wheel flat can be larger than in-phase flats at each wheel due to the presence of pitch dynamics. The parametric study shows that other than speed, depth and length of the flats are most sensitive parameters, and there exists a critical length at each flat depth that leads to the largest impact load.
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Lonsdale, Cameron, Thomas Rusin, and Thomas Hay. "Research to Understand the Effects of Wheel Impact Loads on Wheel Stress Levels." In 2009 Joint Rail Conference. ASMEDC, 2009. http://dx.doi.org/10.1115/jrc2009-63026.
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In recent years wheel impact loads have become a very important topic in the railroad industry due to operational and safety concerns. Much attention has been given to the level of condemnable wheel impact load as determined by wayside detection systems, and to the root causes of tread defects that lead to these wheel impacts. This paper describes physical testing of a wheelset in an instrumented drop hammer system to examine the effects of impact loading on resultant stress levels at various locations on a wheel’s surface. The drop hammer, typically used for evaluation of draft gears, is located at ASF-Keystone in Camp Hill, PA, and can impart dynamic loads up to a maximum of 2,000 kips, which is well in excess of typical wheel impact loads recorded by wayside impact detection systems. Impact loads for drop hammer wheel testing were generally confined to a maximum of approximately 200 kips. Finite element analysis (FEA) modeling using only mechanical tread loading was conducted to determine the high stress locations for the wheel design and to correlate strain gauge results for static loading on the wheel. The instrumented drop hammer used for wheel impact testing is described, and wheel strain gauge issues are discussed. Vertical split rim wheel failures are described and are briefly reviewed. The implications of impact loading for vertical split rim wheel failures are discussed and recommendations for future work are offered.
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Woodrooffe, J. H. F., and P. A. LeBlanc. "The Influence of Suspension Variations on Dynamic Wheel Loads of Heavy Vehicles." In SAE International Truck and Bus Meeting and Exposition. 400 Commonwealth Drive, Warrendale, PA, United States: SAE International, 1986. http://dx.doi.org/10.4271/861973.
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Fairbanks, Gary, Harold Weisinger, Steven Zuiderveen, Anand Prabhakaran, and Tanner Buel. "Dynamic Load Augment From Steam Locomotives." In 2016 Joint Rail Conference. American Society of Mechanical Engineers, 2016. http://dx.doi.org/10.1115/jrc2016-5839.
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Railroad bridges experience dynamic wheel load augment from rolling stock that cross the bridges, due to nominal bridge and suspension dynamics, as well as anomalies such as wheel flats. The level of dynamic augment is particularly high for steam locomotives due to the hammer blow effect associated with the driven wheels. Tests conducted in the early-mid 20th century had quantified some of these effects, and the resulting findings have been part of the impact formulae presented in the AREMA Railway Engineering Manual. However, there was concern that the impact associated with some of the non-cross counter-balanced, lighter, older locomotives, could be higher than specified by AREMA formulae. This paper describes the methodology and results from a series of tests that evaluated the levels of dynamic augment experienced by railroad track and an exemplar bridge under a set of narrow gauge steam locomotives, and compares the measurements to the design values specified in the AREMA Manual. Vertical and lateral loads on railroad track, and strain levels on multiple critical bridge members were measured under three different classes of light, narrow gauge steam locomotives, over a range of operating speeds and conditions. The tests were conducted on a 120 ft span, through truss bridge, and adjacent track on a tourist railroad. Dynamic augment values measured during the tests were generally lower than the values expected from AREMA formulae. Similarly, the peak lateral loads measured appear to be nominal and lower than the AREMA prescribed values. However, it should be kept in mind that these results are from tests conducted with three relatively light, narrow gauge locomotives, on specific bridge and track, whereas, the AREMA formulae are intended to cover a wider range of conditions. These tests tend to show that the legacy standards are conservative and are applicable to calculating regulatory required bridge loads where steam locomotives are concerned.
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Pan, Ziheng, Xiaowu Zhang, Emilia Silvas, Huei Peng, and Nikhil Ravi. "Optimal Design of All-Wheel-Drive Hybrid Pick-Up Trucks." In ASME 2015 Dynamic Systems and Control Conference. American Society of Mechanical Engineers, 2015. http://dx.doi.org/10.1115/dscc2015-9701.
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Both fuel economy and launching/towing performance are important for pick-up trucks. All-wheel-drive (AWD) and multimode operations are important to ensure efficient operations in a wide range of speeds and road loads. In this paper, a systematic methodology is developed and applied to the screening and evaluation of AWD multi-mode hybrid trucks. It is a four-step design process that uses automated modeling techniques, exhaustive search, and a near-optimal control strategy to obtain optimal designs. A case study was conducted to identify superior designs for an imagined hybrid electric Ford F-150 light truck.
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Hu, Hanbing, and Hans Brinkman. "Key Factors of Subgrade Influencing Dynamic Wheel/Rail Loads at Railway Transition Zones." In Second International Conference on Geotechnical and Earthquake Engineering. Reston, VA: American Society of Civil Engineers, 2013. http://dx.doi.org/10.1061/9780784413128.012.
Full textReports on the topic "Dynamic wheel loads"
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Heymsfield, Ernie, and Jeb Tingle. State of the practice in pavement structural design/analysis codes relevant to airfield pavement design. Engineer Research and Development Center (U.S.), May 2021. http://dx.doi.org/10.21079/11681/40542.
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An airfield pavement structure is designed to support aircraft live loads for a specified pavement design life. Computer codes are available to assist the engineer in designing an airfield pavement structure. Pavement structural design is generally a function of five criteria: the pavement structural configuration, materials, the applied loading, ambient conditions, and how pavement failure is defined. The two typical types of pavement structures, rigid and flexible, provide load support in fundamentally different ways and develop different stress distributions at the pavement – base interface. Airfield pavement structural design is unique due to the large concentrated dynamic loads that a pavement structure endures to support aircraft movements. Aircraft live loads that accompany aircraft movements are characterized in terms of the load magnitude, load area (tire-pavement contact surface), aircraft speed, movement frequency, landing gear configuration, and wheel coverage. The typical methods used for pavement structural design can be categorized into three approaches: empirical methods, analytical (closed-form) solutions, and numerical (finite element analysis) approaches. This article examines computational approaches used for airfield pavement structural design to summarize the state-of-the-practice and to identify opportunities for future advancements. United States and non-U.S. airfield pavement structural codes are reviewed in this article considering their computational methodology and intrinsic qualities.