Journal articles: 'Oversize loads'

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Skowrońska, Agnieszka, and Łukasz Kołodziejczyk. "Przewozy ładunków wielkogabarytowych w pojazdach nienormatywnych." Gospodarka Materiałowa i Logistyka 2020, no. 7 (July 20, 2020): 2–14. http://dx.doi.org/10.33226/1231-2037.2020.7.1.

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Semenov, Iouri, and Magdalena Kaup. "Risk management of oversize cargo transport." WUT Journal of Transportation Engineering 129 (June 1, 2020): 63–71. http://dx.doi.org/10.5604/01.3001.0014.3142.

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The article examined the selected problems in traffic caused by the abnormal loads transportation. The authors take into account the uniqueness of such cargoes, which requires an individual approach to the organization and implementation of their delivery from origin to destination. In addition, consider donating the need to eliminate of the numerous difficulties when transporting such abnormal loads as well as re-duction high risk transportation. Also indicated that the solution to these problems is possible through the wider application of risk management methods of the road traffic, the reduction of various threats and probabilities of their occurrence in the context of the traffic flow disruption analysis.

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Wang, Chun Sheng, Gan Li, Guo Dong Guan, and Yu Jiao Wang. "Fatigue Truck Load and Fatigue Life Evaluation of Concrete Bridges for Shaanxi Province." Advanced Materials Research 255-260 (May 2011): 1299–302. http://dx.doi.org/10.4028/www.scientific.net/amr.255-260.1299.

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In the past ten years, considerable increases in traffic volume and vehicle loads have caused obviously fatigue damage in existing highway reinforced concrete bridges in China. Some highway reinforced concrete bridges were damaged seriously, leading to the whole bridge collapse sometimes because of overloading and oversize trucks. In order to observe the highway load character in Shaanxi province, truck weigh device is set up in highway pavement to measure axle weights and axle spacing. Based on these data, it can be classified and generalized the different classes of vehicles, and drawn out the simplifying fatigue truck model in Shaanxi province. Furthermore, the fatigue truck model was used to evaluate the fatigue life and service safety of typical concrete bridges.

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Doležel, Jiří, Drahomír Novák, and Jan Petrů. "Assessment of the transportation route of oversize and excessive loads in relation to the load-bearing capacity of existing bridges." IOP Conference Series: Materials Science and Engineering 236 (September 2017): 012070. http://dx.doi.org/10.1088/1757-899x/236/1/012070.

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Wu, Dayong, Junxuan Zhao, Honchao Liu, and Changwei Yuan. "The assessment of damage to Texas highways due to oversize and overweight loads considering climatic factors." International Journal of Pavement Engineering 20, no. 7 (July 26, 2017): 853–65. http://dx.doi.org/10.1080/10298436.2017.1353392.

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Wang, Chung Sheng, Xiao Hong Dong, Wen Hui Miao, and Gan Li. "Fatigue Safety Evaluation of Existing Reinforced Concrete Bridges." Key Engineering Materials 413-414 (June 2009): 749–56. http://dx.doi.org/10.4028/www.scientific.net/kem.413-414.749.

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Generally, fatigue has not been considered as a key problem in the design of reinforced concrete bridges. Until the 1960s, reinforcement was mild steel and the stresses permitted in the steel bar and the concrete were such that fatigue and fracture failure was believed to be impossible. With the developments of reinforced concrete structures, higher working stresses were permitted and, in particular, high yield reinforcing bars were introduced. Design rules were issued to control cracking and to prohibit welding of reinforcement unless the risk of fatigue was negligible. In recent years, great deals of researches have been carried out, leading to a better understanding of the fatigue behaviors in concrete structures. Some studies showed that fatigue could occur in reinforced concrete structures in combination with other causes of deterioration. In the past eight years, considerable increases in traffic intensity and wheel loads have caused obviously fatigue damage in reinforced concrete structures in China. Some reinforced concrete bridges were damaged seriously, leading to the whole bridge collapse sometimes because of overloading and oversize trucks. So how to evaluate the fatigue safety of existing reinforced concrete bridges is an urgent problem in China. In the current paper, the assessment models of existing reinforced concrete bridges based on S-N curve and fracture mechanics approach were proposed considering the effect of overloading and oversize trucks. Finally the assessment method based on S-N curve and in-situ monitoring data was applied to a case study bridge.

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WIERZBICKA, Aleksandra, and Mariusz KMIECIK. "Abnormal load transport in the context of urban logistics." Scientific Papers of Silesian University of Technology. Organization and Management Series 2020, no. 146 (2020): 499–508. http://dx.doi.org/10.29119/1641-3466.2020.146.35.

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Purpose: The goal of the article is to present oversized transport in the context of urban logistics as the impact of available urban infrastructure, documentation and means of transport on the flow of oversized cargo between the place of loading and the place of receipt. Abnormal load transportation is carried out with the use of public and private roads. It affects the infrastructure and safety of the city through which it takes place, because usually a given section of the road is not excluded during the journey. Design/methodology/approach: The article is based on a broad analysis of Polish and foreign literature. The article also contains an example of the organization of abnormal load transport by one of the Polish enterprises, which was awarded the prestigious “ESTA Awards of excellence 2017” in the category of transport over 120 tonnes. Findings: Oversized transport has a big impact on the temporary functioning of freight flows in the city. The city's spatial development and legal norms significantly influence the oversize transport reduction. It is interesting area of research developing in the future. Originality/value The article shows oversized transport in the context of the city and freight flows in the city.

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Machelski, Czesław, and Maciej Hildebrand. "Strengthening of a road bridge due to a very large load." Transportation Overview - Przeglad Komunikacyjny 2017, no. 8 (August 1, 2017): 58–66. http://dx.doi.org/10.35117/a_eng_17_08_06.

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Extremely heavy oversized transport is considered in the paper. Such oversized loads appears occasionally along the road network due to the restrictions of load capacity of bridges. The results of the analyses involved in the paper shows that old bridges as well as new ones are not adapted to such oversized loads. The strengthening or reconstructions of structural ele-ments are required as presented in the paper. The final remark refers to the administrative un-derstanding of the load capacity of the bridge which is based on the total weight of a vehicle. Such approach of the load capacity is not precise.

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Andrews, Tony D. "Projectile Driving Band Interactions With Gun Barrels." Journal of Pressure Vessel Technology 128, no. 2 (January 3, 2006): 273–78. http://dx.doi.org/10.1115/1.2172965.

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This paper discusses results from a series of trials carried out to determine the effect of the projectile driving band on the stress applied to a 155mm gun barrel during firing. The interference between the driving band and gun barrel can apply significant loads to the barrel and, in extreme cases, lead to premature cracking and failure of the barrel. Strain gage data from firing trials has been used to characterize the external strain from firing different projectiles and charges to identify potential problems and provide information for fatigue analysis. Very high band strains were routinely measured under “oiled bore” conditions, i.e., after barrel cleaning and also during the first one to three rounds of a serial following a long pause in firing, such as at the start of a day’s firing. In general, the strain associated with the driving band was seen to decrease with increased charge zone, barrel wear, and, at higher charge zones, distance along the barrel. In the majority of tests fired at maximum charge, there was no strain peak associated with the driving band in the forward part of the barrel. In conjunction with these experimental observations, a laboratory study has been carried out on the effect of a narrow pressure band on the deformation of a thick-walled tube. An apparatus was constructed in order to pressurize a known length of a smooth-bore cylinder. Sealing width at the edges of the band was minimized to reduce edge effects, and an oversize pressurized “cap” was used to ensure that the bandwidth remained constant during the experiments. Spacer disks were used to vary the bandwidth and also to adjust the cylinder position relative to the band. Measured external strains on the tubes were compared to calculations based on analytical solutions for step pressure changes and are shown to be in good agreement.

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Drozd, Jan, and Jiří Neubauer. "Use of an aerial reconnaissance model during the movement of oversized loads." Journal of Defense Modeling and Simulation: Applications, Methodology, Technology 17, no. 4 (July 29, 2019): 447–56. http://dx.doi.org/10.1177/1548512919866928.

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The paper sets out the results of an experiment carried out using the Virtual Battle Space 2 simulator to verify the applicability of an autonomous unmanned aerial system (UAS) reconnaissance model when moving oversized loads. The model is originally implemented within a decision-support system under military conditions. The aim of the experiment is to verify the possibilities of using the model for civilian needs. The basic output of the experiment presented in the paper is confirmation that the autonomous UAS reconnaissance model can be applied in the actual transportation of oversized loads: the experiment confirms the author’s hypothesis. Based on the result of the experiment it is possible to state that a slightly modified UAS model can significantly influence the execution phase of the oversized load movement in a positive way. It shows that the use of the model reduces the time of the movement and avoids unexpected interferences.

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Popkowski, Tadeusz, and Dmytro Bugayko. "Modern challenges of dangerous and extraordinary goods transportations." Electronic Scientific Journal Intellectualization of Logistics and Supply Chain Management #1 2020 1, no. 3 (October 30, 2020): 54–61. http://dx.doi.org/10.46783/smart-scm/2020-3-5.

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Dangerous goods - goods which, by the nature of their physical characteristics, chemical composition, dimensions, or other specific features and nature (live animals or fish), for some reason endanger human life or health, the environment natural or general order or material goods, including those with features of the principles of humanitarianism. The transport of dangerous and oversize goods is one of the most difficult specialties in the field of goods transport in public transport, in particular in road and rail transport. Such transport is regulated by a number of legal acts that do not apply to companies carrying out tasks related to the transport of loads, the so-called neutral. The United Nations has created a closed TN directory, giving everyone a four-digit "UN number", at the same time dividing them into classes depending on the threat or the predominant threat. The provisions of the ADR agreement relate, inter alia, to the rules (requirements) for TN transport in terms of limiting the possible effects of a potential release of hazardous substances (e.g. as a result of road or rail collisions), as well as, above all, the forms and principles of preventing the possibility of such events. The transport of dangerous goods is a special type of transport and it is subject to specific legal provisions, meeting and observing a number of specific requirements. The safety of this type of transport depends on the proper organization of its transport and the maximum involvement of participants in the entire process. The organization of the transport of hazardous materials requires a comprehensive, comprehensive view of the vehicle, packaging and cargo (means of transport and packaging should be adapted to the transported goods) as well as people involved in the preparation of transport, drivers with appropriate authorizations and training, setting the route, securing this routes in terms of maintaining safety in the event of an emergency. The article offers the author's approaches to the investigation of modern challenges of dangerous and extraordinary goods transportations.

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Monteiro, Sandra, Alfredo Dias, and Sérgio Lopes. "Distribution of Concentrated Loads in Timber-Concrete Composite Floors: Simplified Approach." Buildings 10, no. 2 (February 18, 2020): 32. http://dx.doi.org/10.3390/buildings10020032.

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Timber-concrete composite (TCC) solutions are not a novelty. They were scientifically referred to at the beginning of the 20th century and they have proven their value in recent decades. Regarding a TCC floor at the design stage, there are some assumptions, at the standard level, concerning the action of concentrated loads which may be far from reality, specifically those associating the entire load to the beam over which it is applied. This naturally oversizes the beam and affects how the load is distributed transversally, affecting the TCC solution economically and mechanically. Efforts have been made to clarify how concentrated loads are distributed, in the transverse direction, on TCC floors. Real-scale floor specimens were produced and tested subjected to concentrated (point and line) loads. Moreover, a Finite Element (FE)-based model was developed and validated and the results were collected. These results show that the “loaded beam” can receive less than 50% of the concentrated point load (when concerning the inner beams of a medium-span floor, 4.00 m). Aiming at reproducing these findings on the design of these floors, a simplified equation to predict the percentage of load received by each beam as a function of the floor span, the transversal position of the beam, and the thickness of the concrete layer was suggested.

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Petraska, Arturas, Aldona Jarasuniene, and Kristina Ciziuniene. "Routing Methodology for Heavy-weight and Oversized Loads Carried by Rail Transport." Procedia Engineering 178 (2017): 589–96. http://dx.doi.org/10.1016/j.proeng.2017.01.114.

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Tabsh, Sami W., and Muna Tabatabai. "Live Load Distribution in Girder Bridges Subject to Oversized Trucks." Journal of Bridge Engineering 6, no. 1 (February 2001): 9–16. http://dx.doi.org/10.1061/(asce)1084-0702(2001)6:1(9).

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Baranovskiy, Mikhail, Vladimir Tarasov, and Sergei Zimin. "The Typical Roof Structure Project Based on Trusses Made of Roll-Welded RHS Pipes Development." Applied Mechanics and Materials 725-726 (January 2015): 774–83. http://dx.doi.org/10.4028/www.scientific.net/amm.725-726.774.

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Standardization and unification of elements, constructions and design solutions is one of the main ways to reduce the complexity and cost of the construction.Standard designs of truss coatings with a 10% slope for 24, 30, 36 meters spans were developed in this article for different load combinations.Stress calculation and truss elements dimensioning was made with the SCAD Office software complex. Then the relationship between the thickness of the section, span and load was defined, and the limits of various sizes of the accepted bottom chord connecting block.Designed series of truss structures with a 10% slope and 24, 30, 36 meters spans covers a range of line loads from 1,3 t/m to 3.3 t/m. In comparison with the truss structures series Molodechno it has a lower metal consumption by reducing the cross section of the upper chords due to vertical elements adding. Transportation of a 12-meter section falls under the category of oversized transportation.

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Chee, Li Ping, Esther C. L. Goh, and Leon Kuczynski. "Oversized Loads: Child Parentification in Low-Income Families and Underlying Parent–Child Dynamics." Families in Society: The Journal of Contemporary Social Services 95, no. 3 (July 2014): 204–12. http://dx.doi.org/10.1606/1044-3894.2014.95.26.

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Iatan, Radu, Mihai Stătescu, and Cristina Salca. "The Stability of Longitudinal Movement During the Transportation of Industrial Oversized Equipment on a Platform with an Even Number of Axles. General Case." Scientific Bulletin of Valahia University - Materials and Mechanics 15, no. 12 (April 25, 2017): 43–47. http://dx.doi.org/10.1515/bsmm-2017-0008.

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Abstract It is known that the transportation of oversized technological equipment raises particular poroblems, both from the economical and technicall point of view. Knowing the loads in the platform-equipment assembly, the intensity and the direction of the wind loads, the condition of roads and the way these act is imperative. The present paper seeks to determine the expression of the loads obtained on a platform with an even number of axles, loaded with a technological equipment and neglecting or not the deformation of the suspensions and tires.

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Dzhakhiaeva, S., and K. Klimova. "WAYS OF SOLUTION LOGISTIC TASKS OF TRANSPORTATION THE LONG LOADS FOR EXAMPLE WIND TURBINE BLADES." EurasianUnionScientists 7, no. 11(80) (December 14, 2020): 26–31. http://dx.doi.org/10.31618/esu.2413-9335.2020.7.80.1139.

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The article deals with the optimization of logistics operations for the transportation and reloading of wind turbine blades. The main directions of technical coordination of water and road transport for the implementation of the possibilities of transportation of oversized cargo have been determined. A method of transportation, as well as reloading from an object of a rolling stock of water transport to a road transport, is proposed.

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Petrů, Jan, and Vladislav Křivda. "HEIGHT AND WIDTH PARAMETERS FOR ENSURING PASSAGE OF EXCESSIVE LOADS ON ROADS." Acta Polytechnica 57, no. 3 (June 30, 2017): 209–17. http://dx.doi.org/10.14311/ap.2017.57.0209.

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<p>The article deals with the problem of passage of excessive transports on the roads and ensuring the necessary height and width parameters for this transport in the Czech Republic. Currently is lack of regulations for the design of communications for transit of excessive and oversized cargo in the Czech Republic. On the basis of these aspects the research in this area was carried out and the parameters were set to ensure the passage of excessive loads on the road. The article describes the issue of transportation in the Czech Republic, created database of transports with its resulting statistical analysis. It also describes the procedure for determining the resulting parameters, which should serve as a basis for the legislation and technical conditions.</p>

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Atanasovska, I., R. Mitrović, D. Momĉilović, and A. Subic. "Analysis of the Nominal Load Effects on Gear Load Capacity Using the Finite-Element Method." Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science 224, no. 11 (September 10, 2010): 2539–48. http://dx.doi.org/10.1243/09544062jmes2508.

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This research investigates the effects of the nominal load value on load distribution of simultaneously meshing gear teeth pairs, and on the involute gear load capacity. The research results presented in this article confirm that the nominal load value has a significant influence on the gear load capacity calculations. However, this influence is generally neglected in standard gear calculations, which can result in oversized gear dimensions. This can lead to inadequate gear designs in practice due to increased demand for reduced gear size and weight in modern machinery. The article provides a detailed description of the iterative numerical method developed in this research to support the modelling and analysis of load distribution in meshed gears using the finite-element method.

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Rackov, Milan, Siniša Kuzmanović, Ivan Knežević, Maja Čavić, Marko Penčić, Darko Stefanović, Victor E. Starzhinsky, Sergey V. Shil’ko, and Vladimir B. Algin. "The Influence of the Bearing Lifetime on the Performance of Universal Gear Drives with High Gear Ratio Values." MATEC Web of Conferences 287 (2019): 01022. http://dx.doi.org/10.1051/matecconf/201928701022.

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The problem of defining the load (nominal torque on the output shaft - T2N) of universal gear drives depending on the size of the gear ratio is analysed in this paper. It is logical that the load capacity of gear drive depends on the weakest gear component. Since the gears are the most expensive components of gear unit, it tends to maximize their performance. However, for low gear ratio, i.e. for high speeds, the bearings often limit their load capacity since the same bearings are used in all transmission ratios because it is not practiced to oversize the bearings at low speeds. Nowadays, when high values of gear ratio are used, it is interesting to consider the dependence of the nominal torque at the output regarding to gear ratio and operating life of the unit.

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Petru, Jan, and Vladislav Krivda. "The Process of Setting the Parameters for Ensuring Passage of Oversized Cargos." Baltic Journal of Road and Bridge Engineering 14, no. 3 (September 26, 2019): 425–42. http://dx.doi.org/10.7250/bjrbe.2019-14.451.

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Engineering and the industry very often produce above-standard products concerning their dimensions and weights. There is often a problem with the transport of these products both within Europe and in subsequent transport all around the world. Because of these reasons, several projects to remedy the situation were implemented in the Czech Republic. The article describes the results of many years of research, which observed ensuring the passage of oversized cargos on roads. Further, the measurements, which were carried out, are presented in this paper − the measurement of an oversized vehicle using Global Positioning System devices, creation and modelling of missing cars in programs to verify the swept path, comparison of created models with the measurement using Global Positioning System devices. Then the results of the implemented researches, the suggested parameters, and modelled cars are used for the suggestion of technical parameters of backbone network of roads. On these roads, the loads are transported. The results are also used for verification of critical points of the route, e.g. problematic places and intersections.

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Petru, Jan, Jiri Dolezel, and Vladislav Krivda. "Assessment of the transport routes of oversized and excessive loads in relation to the passage through roundabout." IOP Conference Series: Materials Science and Engineering 236 (September 2017): 012033. http://dx.doi.org/10.1088/1757-899x/236/1/012033.

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Riise, Raymond, and Bjørn R. Sørensen. "The Influence of Oversized Boilers on Power Efficiency, Energy Consumption and Cost in Energy Flexible Heat Stations. Part 1." Applied Mechanics and Materials 291-294 (February 2013): 1816–25. http://dx.doi.org/10.4028/www.scientific.net/amm.291-294.1816.

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Oversized boilers in in-house heat stations are relatively common. This study demonstrates the effect of installed overcapacity in heat stations with regard to the buildings heat load. Potential energy savings are calculated on basis of a heat station containing both fuel oil boiler and electric boiler. Correct installed capacity is defined as the capacity of a boiler designed to meet the design outdoor temperature, DOT. The baseline for normal consumption has been defined by utilization of correct designed boilers operated under various climatic conditions for a normal year. This baseline has then been compared to consumption calculation done with oversized boiler capacity. The energy consumption calculation is done on an hourly basis for one year. The results show a clear connection between the boiler size, boiler efficiency and potential savings in energy and cost.

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Yik, F. W. H., W. L. Lee, J. Burnett, and P. Jones. "Chiller Plant Sizing by Cooling Load Simulation as a Means to Avoid Oversized Plant." HKIE Transactions 6, no. 2 (January 1999): 19–25. http://dx.doi.org/10.1080/1023697x.1999.10667801.

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Stahl, Jens, Isabella Pätzold, Lucas van den Bosch, Alexander Kindsmüller, Roland Golle, and Wolfram Volk. "The Frictional Force between Slug and Die in Shear Cutting after Material Separation." Key Engineering Materials 883 (April 2021): 285–93. http://dx.doi.org/10.4028/www.scientific.net/kem.883.285.

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Frictional forces in sheet metal blanking are central in different aspects, e.g. in wear prediction, validation of simulation models or in so called slug pulling. The latter is a phenomenon where the slug is pulled out of the die by the punch after the sheet metal is separated. This leads to process disturbances reaching from a blocked belt feeder up to severe tool damage caused by the simultaneous cutting of the slug and the sheet metal strip. A sufficiently high frictional force between the slug and the die prevents this effect. Despite its importance, this force and its causes have not yet been investigated in detail. A method was developed in this paper to measure the frictional force between slug and die. A shear cutting tool with an integrated piezoelectric load cell and an inductive position sensor was used on a stamping press to cut sheet metal made of CuSn6 (R350, thickness 1 mm). The die clearance, the punch edge radii and the lubrication conditions were varied. A larger die clearance resulted in a lower frictional force while a larger punch edge radius increased it significantly. Lubrication reduced the frictional force, especially for small die clearances. Finally, the cause of the frictional force was investigated by identifying the relevant springback modes of the slugs. This was carried out by correlating the slugs' deflection, oversize, and clean cut height with the frictional force. Especially the slug oversize, i.e. the difference between the slug's diameter and the die's inner diameter, revealed a strong correlation. Calculations showed that the deformation in radial direction is the main cause of the frictional force between slug and die. It suggests that the slug oversize is a good measure for the magnitude of the frictional force.

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Duan, Qing Song, Cun Ming Ma, and Bin Xie. "Research on Aerodynamic Impacts of Snow on Bridge Decks." Advanced Materials Research 774-776 (September 2013): 68–72. http://dx.doi.org/10.4028/www.scientific.net/amr.774-776.68.

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With the development of economy and technology, many long span bridges have been constructed. However, oversize thickness and long duration of snow on these long span bridges might lead to security issues. The computational fluid dynamics software FLUENT is employed to simulate the snow effect on the bridges. According to the two-phase fluid theory, the relationship between air phase and snow phase is one-way coupling. The corresponding changes of snow load on the bridge deck under the action of strong winds are studied in this paper and the comparative analysis about aerodynamic impacts before and after the snow are conducted as well. According to the results, the snow has notable influence on the aerodynamic characteristics of bridge decks. Keywords: computational fluid dynamics; two-phase fluid theory; snow load; aerodynamics;

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Didkovskiy, Arkadiy, Ekaterina Mukhina, and Gleb Stanishevskiy. "Developing of transport airship for delivery oversized cargo to vostochny cosmodrome." Perm National Research Polytechnic University Aerospace Engineering Bulletin, no. 63 (2020): 23–29. http://dx.doi.org/10.15593/2224-9982/2020.63.03.

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An overview of existing methods of delivering oversized cargo using water, rail, road, air and airship transport, an analysis of the world experience in creating lighter-than-air aircraft and identified the most urgent tasks for this type of vehicles in the field of rocket and space technology, in particular, transportation of oversized elements of super-heavy launch vehicles from manufacturers to the Vostochny cosmodrome, search and rescue of astronauts, evacuation of spent stages from fall fields to disposal points and transportation of oversized trusses. The goals and objectives of this work are defined: review of existing projects of transport airships and study of their designs, development of the layout of a transport airship for delivering stages of superheavy launch vehicles from manufacturers to the Vostochny cosmodrome, calculation of the characteristics of the main systems and detailing the design of the vehicle. As exceptional design solutions, we tested the power scheme of gas shells based on supercharged spiral pneumatic structures that allow you to thermostat the carrier gas and fold the shell for storage, as well as a tangential system for blowing the aerodynamic shell, which allows you to reduce the drag of the device. Based on the developed layout, a simplified mathematical model of the device was created, which allows determining the optimal design parameters. These parameters were used for detailed development of each of the systems, then iterative calculation was performed. As a result, the design of a transport airship for the delivery of oversized elements from manufacturers to the Vostochny cosmodrome was developed and its main technical parameters were determined: load capacity-100 tons, cruising speed-126 km / h, flight range-10 thousand km.

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Hochmann, David, and Lucien Opitz. "Method for instrumentation of orthotic joints for measurement of internal joint loads." Current Directions in Biomedical Engineering 3, no. 1 (March 1, 2017): 35–38. http://dx.doi.org/10.1515/cdbme-2017-0008.

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Abstract:Introduction:The lack of knowledge of mechanical loads in orthotic joints can lead to oversized or breaking components. Previous studies suffer from small sample size and technical limitations. The goal of this study was to develop and validate a method that allows the direct measurement of moments in sagittal, frontal and transverse planes in knee and ankle joints of existing custom made orthoses.Methods:We developed a modular measurement system based on standard joint components, which were instrumented with strain gauges. To ensure sufficient signals and reduce cross talk an iterative approach based on FEM simulation was utilized. The system also contains inertial sensors for mobile gait analysis.Results:Instrumented joints show good results regarding linearity, hysteresis and cross talk. First pilot trials with post-polio and ICP patients demonstrated that joint loads depend on several factors and not solely on body weight. If combined with conventional gait analysis, measurement results can characterize the individual muscle situation of the patient.Conclusion:A novel method for obtaining data on loads in orthotic components was developed and validated. It provides the basis to develop safety testing standards and clinical guidelines, as well as allowing individual optimization of orthotic devices.

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Song, Jian Yong, Ya Mei Yu, and Shuo Zhang. "Initial Imperfection Simulation and Effect on Shear Buckling of Corrugated Steel Webs." Advanced Materials Research 308-310 (August 2011): 2463–70. http://dx.doi.org/10.4028/www.scientific.net/amr.308-310.2463.

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The nonlinear shear buckling of corrugated steel webs is completed by ANSYS. Consistent mode imperfection method is adopted for simulating corrugation configuration imperfection of corrugated steel plate, shear buckling calculation analysis result shows that ultimate shear buckling load of corrugated steel webs is decreased with increasing in corrugation configuration imperfection. Analysis results shows that oversized corrugation configuration imperfection will decrease the ultimate shear buckling load of corrugated steel webs, but premature buckling caused by steel plate thickness imperfection of corrugated steel webs is much better than plain steel webs, and the ultimate shear buckling load and buckling mode will not be much effected by such steel plate thickness imperfection. On this basis, the influences of corrugation configuration to ultimate shear bucking load and buckling mode are investigated.

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Pavier, M. J., C. G. C. Poussard, and D. J. Smith. "Finite element modelling of the interaction of residual stress with mechanical load for a crack emanating from a cold worked fastener hole." Journal of Strain Analysis for Engineering Design 33, no. 4 (May 1, 1998): 275–89. http://dx.doi.org/10.1243/0309324981512995.

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A three-dimensional finite element simulation has been conducted for the cold working of a fastener hole in an aluminium plate. The simulation predicts the residual stress distribution resulting from the cold working process where an oversize mandrel is pulled though the fastener hole. Following the cold working simulation, unidirectional tensile mechanical load is applied to the plate and the resulting redistribution of stress predicted. Parallel through-the-thickness cracks emanating from the hole are then introduced into the model and crack opening displacements and stress intensity factors are predicted along the crack front as a function of applied mechanical load. The finite element simulation shows that cold working has a beneficial effect by reducing the stress intensity factor for a crack under applied mechanical load compared to a non-cold-worked plate. However, this improvement is less than would be expected if the cold working process is idealized as the application of a uniform radial expansion at the hole edge.

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Gooseff, Michael N., David Van Horn, Zachary Sudman, Diane M. McKnight, Kathleene A. Welch, and William B. Lyons. "Stream biogeochemical and suspended sediment responses to permafrost degradation in stream banks in Taylor Valley, Antarctica." Biogeosciences 13, no. 6 (March 21, 2016): 1723–32. http://dx.doi.org/10.5194/bg-13-1723-2016.

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Abstract. Stream channels in the McMurdo Dry Valleys are characteristically wide, incised, and stable. At typical flows, streams occupy a fraction of the oversized channels, providing habitat for algal mats. In January 2012, we discovered substantial channel erosion and subsurface thermomechanical erosion undercutting banks of the Crescent Stream. We sampled stream water along the impacted reach and compared concentrations of solutes to the long-term data from this stream ( ∼ 20 years of monitoring). Thermokarst-impacted stream water demonstrated higher electrical conductivity, and concentrations of chloride, sulfate, sodium, and nitrate than the long-term medians. These results suggest that this mode of lateral permafrost degradation may substantially impact stream solute loads and potentially fertilize stream and lake ecosystems. The potential for sediment to scour or bury stream algal mats is yet to be determined, though it may offset impacts of associated increased nutrient loads to streams.

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Gooseff, M. N., D. Van Horn, Z. Sudman, D. M. McKnight, K. A. Welch, and W. B. Lyons. "Biogeochemical and suspended sediment responses to permafrost degradation in stream banks in Taylor Valley, Antarctica." Biogeosciences Discussions 12, no. 17 (September 8, 2015): 14773–96. http://dx.doi.org/10.5194/bgd-12-14773-2015.

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Abstract. Stream channels in the McMurdo Dry Valleys are typically wide, incised, and stable. At typical flows, streams occupy a fraction of the oversized channels, providing habitat for algal mats. In January 2012, we discovered substantial channel erosion and subsurface thermomechanical erosion undercutting banks of Crescent Stream. We sampled stream water along the impacted reach and compared concentrations of solutes to the long-term data from this stream (~20 years of monitoring). Thermokarst-impacted stream water demonstrated higher electrical conductivity, and concentrations of chloride, sulfate, sodium, suspended sediments, and nitrate than the long-term medians. These results suggest that this mode of lateral permafrost degradation may substantially impact stream solute loads and potentially fertilize stream and lake ecosystems. The potential for sediment to scour or bury stream algal mats is yet to be determined, though it may offset impacts of associated increased nutrient loads to streams.

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Williamson, Patrick, Aron Lechtig, Philip Hanna, Stephen Okajima, Peter Biggane, Michael Nasr, David Zurakowski, Naven Duggal, and Ara Nazarian. "Pressure Distribution in the Ankle and Subtalar Joint With Routine and Oversized Foot Orthoses." Foot & Ankle International 39, no. 8 (April 26, 2018): 994–1000. http://dx.doi.org/10.1177/1071100718770659.

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Background: Foot orthoses are used to treat many disorders that affect the lower limb. These assistive devices have the potential to alter the forces, load distribution, and orientation within various joints in the foot and ankle. This study attempts to quantify the effects of orthoses on the intra-articular force distribution of the ankle and subtalar joint using a cadaveric testing jig to simulate weight bearing. Methods: Five lower-limb cadaveric specimens were placed on a custom jig, where a 334-N (75-lb) load was applied at the femoral head, and the foot was supported against a plate to simulate double-leg stance. Pressure-mapping sensors were inserted into the ankle and subtalar joint. Mean pressure, peak pressure, contact area, and center of force were measured in both the ankle and subtalar joints for barefoot and 2 medial foot orthosis conditions. The 2 orthosis conditions were performed using (1) a 1.5-cm-height wedge to simulate normal orthoses and (2) a 3-cm-height wedge to simulate oversized orthoses. Results: The contact area experienced in the subtalar joint significantly decreased during 3-cm orthotic posting of the medial arch, but neither orthosis had a significant effect on the spatial mean pressure or peak pressure experienced in either joint. Conclusion: The use of an oversized orthosis could lead to a decrease in the contact area and alterations in the distribution of pressure within the subtalar joint. Clinical Relevance: The use of inappropriate orthoses could negatively impact the force distribution in the lower limb.

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Oswald, Eugen, Mathias Liewald, and Oliver Stephan. "Development of Bionic Design Concepts for Structure Optimisation of Forming Tools According to Production and Stress Constraints." Key Engineering Materials 473 (March 2011): 209–16. http://dx.doi.org/10.4028/www.scientific.net/kem.473.209.

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In the automotive industry, current design and dimensioning of forming tools and bearing tool components occurs according to guidelines. Possible interactions between arising loads as well as dimensioning are empirically estimated. Simulative computations, which are based on CAE-methods, are only realized in special cases. Therefore, most often current standards lead to oversized tools. In consequence, new studies based on CAE-analyses are supposed to investigate new possibilities to design forming tools and components optimized in their structure corresponding to the right distribution of forces and stress. This is made in order to increase reliability during the manufacturing process, as well as the tools’ stiffness and contribute to decrease of investment costs.

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Di Rosa, Ines, Romina Clarioni, Hansjürg Hotz, Rita Pascolini, Francesca Simoncelli, Anna Fagotti, Lorena Morosi, Roberto Pellegrino, and Gaston-Denis Guex. "Bioaccumulation of organochlorine pesticides in frogs of the Rana esculenta complex in central Italy." Amphibia-Reptilia 26, no. 1 (2005): 93–104. http://dx.doi.org/10.1163/1568538053693297.

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AbstractConcentrations of commonly used organochlorine pesticides (OCPs) were determined in tissues of 23 adult and 24 larval water frogs of two coexisting species (Rana lessonae and the hemiclonal hybrid R. esculenta) and in the water of their breeding pond in an agricultural zone in Umbria, central Italy, where increased occurrence of infectious diseases and distinctly oversized tadpoles were recently observed. The concentrations of OCP in tissues of both species were lower than those in the water of their breeding pond, except for DDT, which was more concentrated in adult frogs than in pond water (bioaccumulation factor 7 for R. lessonae, 15 for R. esculenta). Total OCP concentration and adult body weight were positively correlated for both species, which is consistent with bioaccumulation. In accord, adults contained higher OCP concentrations than tadpoles. Oversized tadpoles had higher OCP concentrations than normal tadpoles. Mean OCP concentrations in individual organs were about an order of magnitude higher than those in whole-frog homogenates. They were highest in brain, higher in ventral than in dorsal skin, and moderately high in ovaries; transmission of bioaccumulation loads to the next generation is therefore possible. The observed OCP concentrations appear too low to directly cause mortality in water frogs, but effects of cumulative exposure to low-level pollutants and their synergistic interactions with the effects of other natural and anthropogenic environmental stressors are unknown.

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Baszynski, Marcin, Kacper Sowa, and Stanislaw Pirog. "An Active Power Filter with Energy Storage and Double DC Conversion for Power Surge Compensation." Electronics 9, no. 9 (September 10, 2020): 1489. http://dx.doi.org/10.3390/electronics9091489.

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This paper presents a single-phase power filter with an energy storage bidirectional DC/DC converter, both of which are equipped with separate capacitor-based DC links that provides good transient response and reduce energy storage capacity. The device is dedicated to the compensation of active power surges generated by nonlinear loads characterized by intermittent operation, where the operating time of a device in relation to the idle time is relatively short. As a compensated and filtered object, the single-phase spot welding machine with a thyristor current controller was assumed. In the case of such devices, the feeder has to be dimensioned for the peak loads, which increase the cost of installation—due to the fact that the used components have to be oversized. The proposed solution can produce measurable economic benefits by reducing the rated power necessary to energize periodically operating loads and improve the indicators of electrical energy quality. An elaborated control algorithm based on a switchable control structure provides a fast and good transient response. The work contains a comprehensive analysis of storage sizing, confirmed by simulation results performed in the Matlab and Simulink environment. Based on the analyses carried out, the laboratory model of the device was implemented and experimental verification performed.

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Sprenger, André, Michael Haydn, Serge Ondoua, Lucia Mosch, and Reiner Anderl. "Ontology-Based Information Model for the Exchange of Uncertainty in Load Carrying Structures." Applied Mechanics and Materials 104 (September 2011): 55–66. http://dx.doi.org/10.4028/www.scientific.net/amm.104.55.

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Knowledge about future process properties is crucial for the development of safe and economic products with load carrying structures. Real processes are influenced by uncertainty what causes scattering and deviation from assumed values. As a consequence, products are often oversized or even product failures can occur. To control uncertainty, extensive knowledge about future processes is necessary in the development process. This paper shows an approach for the representation of uncertainty in production-and usage-processes, according to scattering properties and their cause and effect relations. This approach is used as a common platform for storing, locating, comparing and reuse of knowledge about uncertain properties and their relations. The core of the proposed approach is an ontology-based information model with the ability to represent different levels of trusted information in relation to process parameters and cause and effect relations.

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Zhang, Yu Min, Ying Cui, and Jing Liu. "Collapse-Prevention Design and Damage-Reduction Seismic Performance Analysis of Bridges." Applied Mechanics and Materials 638-640 (September 2014): 1997–2000. http://dx.doi.org/10.4028/www.scientific.net/amm.638-640.1997.

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As the crucial junction in transportation lines, more attention should pay to the safety of bridges. However, the collapse of bridges under earthquake threats the safe of lifeline engineering seriously. Unseating prevention devices are the effective structural measure to prevent collapse under unexpected earthquake. The design of unseating prevention devices need not only to meet the deformation demand of bridge during normal operations, but also to limit the oversize displacement under unexpected earthquake. Combined with relational design standards at home and abroad, unseating prevention devices have been designed for bridge to prevent collapse. The research results show that the unseating prevention devices with reasonable parameter will decrease the relative displacement between superstructure and substructure, improve the seismic performance and integrality of bridge, and make the seismic load to be well-distributed among the piers.

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He, Ming, Frank Lam, and Helmut GL Prion. "Influence of cyclic test protocols on performance of wood-based shear walls." Canadian Journal of Civil Engineering 25, no. 3 (June 1, 1998): 539–50. http://dx.doi.org/10.1139/l97-114.

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This paper compares the test results obtained from three cyclic test protocols in a series of studies on lateral resistance of wood-based shear walls built with oriented strand board panels. When the shear walls were subjected to a long sequence of cycle groups, the failure mode was dominated by low cycle fatigue failure of nail connectors which was rarely observed under seismic conditions. Alternate cyclic loading protocols with large amplitude but short sequence allowed shear walls to avoid this type of nail failure. The results also indicate that under the high amplitude short sequence cyclic test protocol, a higher racking resistance of the shear wall can be achieved which approaches the peak loads from monotonic tests.Key words: wood shear wall, oriented strand board, oversized panel, cyclic lateral loading, earthquake, connector failure mode, energy dissipation.

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Gheitasi, Amir, and Devin K. Harris. "Implications of Overload Distribution Behavior on Load Rating Practices in Steel Stringer Bridges." Transportation Research Record: Journal of the Transportation Research Board 2522, no. 1 (January 2015): 47–56. http://dx.doi.org/10.3141/2522-05.

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With the ever-increasing demands for transporting goods and services, transportation officials are facing a growing challenge with the safety of in-service bridges under the passage of oversized and overweight vehicles. Current load rating practices provide the basis for evaluating the operational safety of in-service structures by using engineering judgments and simplifying assumptions. However, a true measure of the system performance under the impact of irregular loading scenarios requires knowledge of different aspects of the system-level characteristics, including the lateral load distribution behavior. In this study, nonlinear finite element analysis has been implemented to evaluate the evolution of load-distributing mechanisms in two representative in-service structures subjected to overloads in the state of Michigan. In addition, rating factors were defined for the selected structures on the basis of the load and resistance factor rating methodology. Results from this study demonstrated that current design and rating practices were overly conservative in predicting the actual distribution behavior and assessing the safety of the in-service structures under the effect of irregular loading conditions. This investigation also highlighted the importance and benefits of implementing a refined method of analysis that can help bridge engineers to support their permit and posting decisions.

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Wolff, Christian V. "“ASEMOS”—Advanced Semisubmersible Mooring System." Marine Technology and SNAME News 22, no. 01 (January 1, 1985): 36–49. http://dx.doi.org/10.5957/mt1.1985.22.1.36.

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The least efficient, yet most popular mooring system on semisubmersibles is the conventional chain-only type. These perform well in shallow to moderate depths, but as water depth increases, so do horizontal excursions of the rig. System efficiency also decreases because more and more of the strength of the chain is required to support its own weight and less is available to provide horizontal restoring forces. This paper describes an advanced mooring system that offers several distinct advantages over the usual alternatives: more elasticity in the mooring line at shallow depths; maximum strength and restoring force at the vessel; lower center of gravity and improved stability; increased variable deck-load capacity; and protection of the winches from wind and sea. One feature that makes the "ASEMOS" system unique is the placement of the mooring winches within the pontoons (Figs. 1 and 2). This location not only protects the winches from the elements, but results in a much lower center of gravity than that of other comparably sized semisubmersible drilling rigs. Another key feature is the use of oversized very heavy chain between the end of the wire rope mooring line and the anchors. This heavy chain provides extra elasticity in the mooring line catenary in shallow depths, and shortens the length of wire rope required to achieve maximum anchor-holding power in deep water. The greater breaking strength of the oversized chain permits the use of a lower-grade steel and avoids the high cost and fatigue problems commonly encountered in other systems.

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Masood, Ali S., and Monica E. Lineberger. "United Kingdom, United Courts? Hierarchical Interactions and Attention to Precedent in the British Judiciary." Political Research Quarterly 73, no. 3 (June 11, 2019): 714–26. http://dx.doi.org/10.1177/1065912919853368.

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Most empirical examinations of hierarchical interactions among the courts are limited to a single judiciary, the American courts. A significant puzzle that remains is the extent to which lower courts in comparative environments follow the legal pronouncements of their court of last resort. We confront this shortcoming by examining lower court adherence to the precedents of the House of Lords in the United Kingdom. As the Law Lords in the United Kingdom primarily oversee a single lower court, the Court of Appeal of England and Wales, this design provides a unique opportunity to assess the factors that influence hierarchical responses to precedent. We offer a framework in which legal, rather than strategic, factors influence the propensity with which lower court judges rely on the precedents of the House of Lords. Using an original data set of over 13,000 lower court responses to the precedents of the House of Lords between 1970 and 2002, our findings challenge the efficacy of principal–agent accounts and shed new light on how horizontal stare decisis influences decision-making behavior within the United Kingdom.

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Ricci, Stefano, and Valentino Meacci. "Simple Torque Control Method for Hybrid Stepper Motors Implemented in FPGA." Electronics 7, no. 10 (October 7, 2018): 242. http://dx.doi.org/10.3390/electronics7100242.

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Stepper motors are employed in a wide range of consumer and industrial applications. Their use is simple: a digital device generates pulse-bursts and a direction bit towards a power driver that produces the 2-phase currents feeding the motor windings. Despite its simplicity, this open-loop approach fails if the torque load exceeds the motor capacity, so the motor and driver should be oversized at the expense of efficiency and cost. Field-Oriented closed-loop Control (FOC) solves the problem, and the recent availability of low cost electronics devices like Digital Signal Processors, Field Programmable Gate Arrays (FPGA), or even Microcontrollers with dedicated peripherals, fostered the investigation and implementation of several variants of the FOC method. In this paper, a simple and economic FOC torque control method for hybrid stepper motors is presented. The load angle is corrected accordingly to the actual shaft position through pulse-bursts and direction commands issued towards a commercial stepper driver, which manages the 2-phase winding currents. Thanks to the FPGA implementation, the control loop updates the electrical position every 50 μs only, thus allowing a load angle accuracy of −1/100 rad for a rotor velocity up to 750 rev/min, as shown in the reported experiments.

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Tabsh, Sami W., and Muna Tabatabai. "Live-Load Girder Distribution Factors for Bridges Subjected to Wide Trucks." Transportation Research Record: Journal of the Transportation Research Board 1696, no. 1 (January 2000): 144–49. http://dx.doi.org/10.3141/1696-56.

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An important problem facing engineers and officials in the United States is the constraint imposed on transportation due to limitations of bridges. These limitations typically constrain vehicles to minimum heights and widths, to minimum and maximum lengths, and to a maximum allowable weight. However, with current demands of society and industry, there are times when a truck must carry a load that exceeds the size and weight of the legal limit. In this situation, the trucking company requests from the state departments of transportation an overload permit. For a truck with a wheel gauge larger than 1.8 m (6 ft), the process of issuing a permit for an overload truck requires a tremendous amount of engineering efforts. This is because the wheel load girder distribution factors (GDFs) in the design specifications cannot be used to estimate the live-load effect in the girders. In some cases, an expensive and time-consuming finite element analysis may be needed to check the safety of the structure. In this study, the finite element method is used to develop a modification factor for the GDF in AASHTO’s LRFD Bridge Design Specifications to account for oversized trucks with a wheel gauge larger than 1.8 m. To develop this factor, nine bridges were considered with various numbers of girders, span lengths, girder spacings, and deck slab thicknesses. The results indicated that use of the proposed modification factor with the GDF in the design specifications can help increase the allowable load on slab-on-girder bridges.

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Chuo, Er Yong, De Qun Wang, and Guo Rui Deng. "The Impact of Road Construction Materials Dynamic Modulus Parameters on Road Surface Shearing Stress." Applied Mechanics and Materials 178-181 (May 2012): 1183–87. http://dx.doi.org/10.4028/www.scientific.net/amm.178-181.1183.

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At the beginning,we used the ABAQUS to establish a two-dimensional finite element model of typical asphalt pavement, and analysised the changing axiom of road surface shearing stress under the half sine wave load. Also, we studied on the impact of damping ratio and the driving speed on shearing stress. Finally, by using SPSS13.0 software to compare the impact of speed, the surface layer material damping ratio, lower modulus ratio, the thickness of the surface layer and the thickness of the subbase. The results show that, to reduce the cracking damage caused by oversized shearing stress in asphalt pavement, we should first consider the damping ratio of surface layer material, and the most effective method is to use the road-building material of high damping ratio to prevent cracks, at the same time we should raise the driving speed.

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Soutis, C., and F. Z. Hu. "Design and performance of bonded patch repairs of composite structures." Proceedings of the Institution of Mechanical Engineers, Part G: Journal of Aerospace Engineering 211, no. 4 (April 1, 1997): 263–71. http://dx.doi.org/10.1243/0954410971532668.

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The compressive behaviour of bonded patch repaired composite laminates is examined. A non-linear stress analysis is performed on a double-lap joint in order to identify critical joint parameters and design an efficient external patch repair. It is found that oversized patches not only increase the structure's weight but also increase the stress concentrations in the repaired region which can cause premature failure. Reducing the patch thickness near the edges of the overlap and increasing the local adhesive thickness decreases the stress concentration in both shear and peel stresses. A three- dimensional finite element analysis is then performed to determine the stresses in the optimum repaired configuration and is used with a stress failure criterion to predict the ultimate failure load. Experimental measurements show that carefully designed bonded patch repairs can recover almost 80 per cent of the undamaged laminate strength.

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Conti, Paolo, Carlo Bartoli, Alessandro Franco, and Daniele Testi. "Experimental Analysis of an Air Heat Pump for Heating Service Using a “Hardware-In-The-Loop” System." Energies 13, no. 17 (September 1, 2020): 4498. http://dx.doi.org/10.3390/en13174498.

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Estimating and optimizing the dynamic performance of a heat pump system coupled to a building is a paramount yet complex task, especially under intermittent conditions. This paper presents the “hardware-in-the-loop” experimental campaign of an air-source heat pump serving a typical dwelling in Pisa (Italy). The experimental apparatus uses real pieces of equipment, together with a thermal load emulator controlled by a full energy dynamic simulation of the considered building. Real weather data are continuously collected and used to run the simulation. The experimental campaign was performed from November 2019 to February 2020, measuring the system performances under real climate and load dynamics. With a water set point equal to 40 °C, the average heat pump coefficient of performance was about 3, while the overall building-plant performance was around 2. The deviation between the two performance indexes can be ascribed to the continuous on-off signals given by the zone thermostat due to the oversized capacity of the heat emission system. The overall performance raised to 2.5 thanks to a smoother operation obtained with reduced supply temperature (35 °C) and fan coil speed. The paper demonstrates the relevance of a dynamic analysis of the building-HVAC system and the potential of the “hardware-in-the-loop” approach in assessing actual part-load heat pump performances with respect to the standard stationary methodology.

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Abramowicz-Gerigk, Teresa, and Zbigniew Burciu. "Design and Operational Innovations in Adapting the Existing Merchant River Fleet to Cost-Effective Shipping." Polish Maritime Research 26, no. 4 (December 1, 2019): 157–64. http://dx.doi.org/10.2478/pomr-2019-0078.

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Abstract Modernisation of the existing river fleet adapted for the local conditions of the Middle and Lower Vistula can be considered as a solution to slow down the progressive decrease of river transport in this area. The implementation of technical improvements, smart technologies and enhancement of transport performance may partially solve the problem of growing demand for multimodal transport of containers and oversized loads in a shorter perspective than the expected period of planned revitalisation of the river. The paper presents investigations on the modernisation of river convoys adapted to the current navigational conditions of the Lower Vistula. The different options have been discussed by the authors with river fleet operators and the best recognised solution was agreed to be the use of river convoys combining modernised motor barges and the pushed barges previously used in this area. Improvement of the transport profitability, reduction of fuel consumption, air pollution and noise can be achieved at minimum costs by modernisation of the main power-propulsion systems of outdated motor barges and the implementation of innovative steering systems on pushed barges. The demand for power-propulsion and manoeuvring performance of modernised convoys is discussed in the paper.

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Lucas, Guilherme B., Bruno A. de Castro, Marco A. Rocha, and Andre L. Andreoli. "Study of a Low-Cost Piezoelectric Sensor for Three Phase Induction Motor Load Estimation." Proceedings 4, no. 1 (February 11, 2019): 46. http://dx.doi.org/10.3390/ecsa-5-05723.

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Due the complexity of control and automation networks in modern industries, sensor-based systems stand out as effective approaches for failure detection in electrical and mechanical machines. This kind of intervention has a high operational value in industrial scenarios, once it can avoid corrective maintenance stops, i.e., before the failure reaches a high level of severity and compromises the machine. Consequently, the development of sensors applied to non-destructive techniques (NDT) for failure monitoring in electrical machines has become a recurrent theme in recent studies. In this context, this paper investigates the application of low-cost piezoelectric sensors for vibration analysis, which is an NDT that has already proved to be efficient for the detection of many structural anomalies in induction motors. Further, the proposed work presents a low-cost alternative approach for expensive commercial sensors, which will make this NDT more attractive for industrial applications. To describe the piezoelectric sensor frequency response, a pencil lead break (PLB) test was performed. After this validation, the Root Mean Square (RMS) value from the voltage samples obtained in the test bench was used as a signal processing method. A comparison between the results for different levels of mechanical load attached to the machine shaft indicated not only the successful performance of the low-cost sensors for load estimation purposes, but also showed that oversized motors may present higher vibration levels in some components that could cause mechanical wearing.

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Journal articles on the topic 'Oversize loads'

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