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1

Quantitative evaluation on dynamics of fixturing system

Numata Raiki, Mori Kotaro, Matsubara Atsushi

Journal of Machine Engineering

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2024

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Vol. 24, No. 1

29--36

EN

When complex and thin-walled workpieces produced for the aircraft industry are machined, they are supported by fixtures to prevent them from easily deforming or vibrating. To support the workpieces effectively, the stiffness of the fixture should be sufficiently high. However, the criteria required for the fixture dynamics to effectively support a workpiece during machining have not been thoroughly investigated. To minimize trial and error, the design parameters required for the fixture should be determined theoretically. Accordingly, this study proposes a method for theoretically determining the design parameters of a fixturing system. The effect of the substructure thickness on the dynamics of the entire structure was evaluated quantitatively using a theoretical model, and the validity of the model was verified experimentally. The stiffness of the entire fixturing system was estimated using the reacceptance coupling method. In addition, the relationship between the thickness of the substructure and stiffness of the entire structure was evaluated.

2

Reduction of dynamic loads in the drive system of mining scraper conveyors through the use of an innovative highly flexible metal coupling

Wieczorek Andrzej Norbert, Konieczny Łukasz, Wojnar Grzegorz, Wyroba Rafał, Filipowicz Krzysztof, Kuczaj Mariusz

Eksploatacja i Niezawodność

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2024

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Vol. 26, no. 2

art. no. 181171

EN

The article provides a discussion on the results of the authors’ original studies of a power transmission system of a mining scraper conveyor coupled with an innovative highly flexible clutch, conducted in operating conditions. The research consisted in establishing the static characteristics of the highly flexible clutch in question, determining the torsional vibrations of the said highly flexible clutch and the vibrations of the transmission housings at a test rig, verifying if the coupling between the innovative flexible clutch and a typical scraper conveyor drive unit was correct, and testing durability of individual components of the highly flexible clutch. Following the aforementioned tests and based on the static characteristics of the highly flexibleclutch examined, one can distinguish three phases of its operation: initial, main, and final –all differing in terms of flexibility. Furthermore, upon increasing the flexibility of the metal clutch, a significant decline in the root mean square (RMS) values of linear vibration accelerations was observed compared to the blocked condition of the clutch. It was further noticed that, as the torsional vibrations of the clutch shaft were increasing, the linear vibrations measured at the transmission bearing housings were decreasing significantly. Based on the tests conducted in operating conditions, it was found that the durability of the flexibilising system (bolt and nut) was sufficient and that there were no thermal effects associated with the motion of the system components.

3

Defect categorization of ribbon blender worm gearbox worm wheel and bearing based on artificial neural network

Barshikar Raghavendra Rajendra, Ghongade Harshvardhan P., Bhadre Anjali A., Pawar Harjitkumar U., Rane Harshal S.

Eksploatacja i Niezawodność

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2024

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Vol. 26, no. 2

art. no. 185371

EN

There is a demand for worm gearboxes in diversified industrial fields that include machinery such as escalators, ribbon blenders, pulverisers, bowl mills, etc. because of their peculiar characteristics like torque and quick retardation. The most commonly occurring defects in a worm gear box are scratches that develop in the worm gear and in bearings. Early defect categorization is required to prevent a sudden breakdown that would decrease production. The defect is depicted in different cases, which include defects in the gear tooth and the outer and inner races of the bearing. In another case, the defect is considered in the gear tooth as well as the bearing. The severity is designated using the ANN. The experiments were performed under these conditions with a good worm gearbox to capture vibration response signatures. Using these values as an input to the ANN, the model is trained. Experimental results show that vibration amplitude increases with fault progression in the worm gearbox, and the trained ANN model effectively categorizes worm gearbox faults with an accuracy of 97.12%.

4

Investigation of The Effect of Mechanical Vibration Applied During Solidification on The Microstructure and Properties of Aluminum 356 Alloy

Özgü Taha Süreyya, Çalın Recept, Tanış Naci Arda

Archives of Foundry Engineering

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2024

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Vol. 24, iss. 1

26--31

EN

Manufacturing by casting method in aluminum and its alloys is preferred by different industries today. It may be necessary to improve the mechanical properties of the materials according to different industries and different strength requirements. The mechanical properties of metal alloys are directly related to the microstructure grain sizes. Therefore, many grain reduction methods are used during production or heat treatment. In this study, A356 alloys were molded into molds at 750°C and exposed to vibration frequency at 0,8.33, 16.66, 25, and 33.33 Hz during solidification. Optical microscopes images were analyzed in image analysis programs to measure the grain sizes of the samples that solidified after solidification. In addition, microhardness tests of samples were carried out to examine the effect of vibration and grain reduction on mechanical behavior. In the analyzes made, it was determined that the grain sizes decreased from 54.984 to 26.958 μm and the hardness values increased from 60.48 to 126.94 HV with increasing vibration frequency.

5

Vibration reduction with rubber-metal cab supports

Bezruchko Alexander Fomich, Zezetko Nikolai Ivanovich, Vainola Vello, Tanaś Wojciech, Szymanek Mariusz

Agricultural Engineering

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2024

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Vol. 28, No. 1

1--8

EN

This paper investigates the possibility of improving the vibration isolation of a tractor cab by changing the stiffness of its rubber-metal supports. A spectral analysis of the vibration isolation properties of these supports is presented. The research was conducted on a BELARUS 1221 tractor at idling, at the maximum engine speed, with no load. The cab was mounted on rubber-metal vibration absorbers of serial design with different rubber hardness. Measurements were made with a first class certified Oktava 101VM instrument with registration of RMS acceleration values, expressed in dB, in the frequency range of 8-1000 Hz. The instrument was set in "local vibration" mode. The AR2082M probe was attached to the respective measurement points using adhesive. Mathematical relationships are given to optimize the work on the development of a new and upgraded design of the rubber-metal supports in use. It is shown that varying the stiffness of the rubber-metal supports has different effects in the low and high frequencies of the spectrum. A stiff support is effective in damping low-frequency vibrations but degrades the support's properties in damping high-frequency vibrations, and vice versa. A soft support is more effective at higher frequencies and reduces the effectiveness of the support at lower frequencies.

PL

Niniejsza praca analizuje możliwość ulepszenia izolacji wibracji w kabinie ciągnika poprzez zmianę sztywności gumowo-metalowych wsporników. Przedstawiono analizę spektralną właściwości izolacji wibracji tychże wsporników. Związki matematyczne zostały podane w celu optymalizacji pracy nad stworzeniem nowego i ulepszonego projektu gumowo-metalowych wsporników. Wykazano, iż różnicowanie sztywności gumowo-metalowych wsporników daje różne efekty w niskich i wysokich spektrach częstotliwości. Sztywny wspornik jest skuteczny w wyciszaniu wibracji o niskiej częstotliwości, ale zmniejsza właściwości wyciszania wibracji o wysokiej częstotliwości i vice versa. Miękkie wsparcie jest bardziej efektywne przy wysokich częstotliwościach i redukuje skuteczność wspornika przy niskich częstotliwościach.

6

Research on the Distribution of Axial Excitation of Positive Pressure Ventilators in the Aspect of Stability Safety of the Load-Bearing Frame

Wieczorek Bartosz, Kaczmarzyk Piotr, Warguła Łukasz, Giedrowicz Marcin, Bąk Damian, Gierz Łukasz, Stambolov Grigor, Kostov Boris

Advances in Science and Technology. Research Journal

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2024

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Vol. 18, no 1

142--154

EN

Positive pressure ventilators are exposed to self-shifting during their operation. The aim of the article was to perform research analysing dynamic excitations resulting from vibrations caused by the operation of the drive system. The tests included four different fans, including one with an electric drive. The tests carried out made it possible to determine the effective RMS R value of vibrations, which is a maximum of 0.970 G, and the direction of the excitation relative to the vertical and horizontal axes. In addition, the values of vibration amplitudes on individual axes of the adopted reference system were determined. In this case, the highest values were measured on the vertical axes for combustion-powered ventilators (vibration value from 20 to 35 m/s2 ) and in the axis along the fan rotor for electric-powered ventilators (vibration value from 1.1 m/s2).

7

Experimental Energy Recovery from a Backpack Using Various Harvester Concepts

Kęcik Krzysztof

Advances in Science and Technology. Research Journal

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2024

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Vol. 18, no 3

67--78

EN

Energy harvesting from human body kinetics is a crucial issue. The primary challenge lies in designing and optimizing the energy converter. This paper presents an analysis of energy harvesting using three variants of electromagnetic harvesters designed for backpack integration. The first harvester comprises a single levitating magnet within a coil. The second concept involves a specially designed oscillating magnet consisting of two divided magnets with a separator. The third harvester variant utilizes two levitating magnets within the coil. The results indicate that, for harmonic excitation, the harvested power is the highest for the classical harvester with a single oscillating magnet. However, when integrated into a backpack, the concept of two levitating magnets proves to be more effective in lower speed ranges.

8

Design of Dry Friction Damper to Reduce Vibration Impacts to Circuit Cards at Critical Frequencies

Kovtun Igor, Goroshko Andrii, Petrashchuk Svitlana

Advances in Science and Technology. Research Journal

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2024

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Vol. 18, no 2

78--87

EN

The paper is focused on providing strength and stiffness for circuit cards exposed to vibration at critical frequencies. Since the dry friction damping is more effective than viscous damping and in case when application of viscous dampers is restricted by electronic package design the dry friction damper is proposed to be embedded to design of enclosure case in order to reduce oscillation amplitudes of circuit cards at critical frequencies. Dry friction damper produces dissipative forces – non-elastic resistance forces due to friction in kinematic pairs undergoing oscillations. The mathematical model has been developed for estimation of maximal dynamic stress and deflection in critical cross-section of circuit card with embedded dry friction damper at critical frequencies. Developed mathematical model specifies minimal limit value for stiffness of dry friction damper, which is used in engineering calculations to determine its geometric parameters. Design of dry friction damper is introduced by semi-elliptical beam with rectangular profile. The effectiveness of dry friction damper to reduce dynamic stress and deflection in circuit cards has been analytically proved and experimentally testified.

9

Examination of a magnetorheological damper control system with vibration energy harvesting

Jastrzębski Łukasz, Sapiński Bogdan

Acta Mechanica et Automatica

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2024

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Vol. 18, no. 1

158--168

EN

The study deals with the experimental examination of a magnetorheological (MR) damper control system with vibration energy harvesting using a specially engineered electronic unit (EU). Unlike a typical MR damper control system, which requires an external energy source, the developed system is powered exclusively by energy extracted from a vibrating structure (mechanical system with one-degree-of freedom) and processed through the EU. The work describes the structure and functions of the EU, presents the test rig and the control algorithm implementation, and discusses the test results of the control system under harmonic kinematic excitations of low frequency range.

10

Line start permanent magnet synchronous motor supplied with voltage containing subharmonics

Gnaciński Piotr, Muc Adam, Pepliński Marcin

Zeszyty Naukowe Akademii Morskiej w Szczecinie

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2023

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nr 74 (146)

28--34

EN

The presented study examines the effect of voltage subharmonics, which relates to components of the frequency less than the fundamental voltage harmonic, and the currents and vibration of the line start permanent magnet synchronous motor. The obtained experimental results corresponded to a production motor with a rated power of 3 kW and a rated speed of 1500 rpm. The main purpose of our study was to highlight that the subharmonic value had a non-linear effect on the vibration level of the considered motor. It was found that for subharmonic values up to approx. 0.5% of the vibration level could be considered acceptable for long-term operation, whereas vibration caused by voltage subharmonics of values greater than approx. 0.8% might promote machine damage.

11

Vibrating moistening of wheat grain

Chornyi Valentyn, Kharchenko Yevgen

Vibrations in Physical Systems

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2023

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Vol. 34, nr 1

art. no. 2023113

EN

The article experimentally established the influence of amplitude, frequency and duration of processing on the efficiency of vibratory wetting of wheat. With increasing amplitude and frequency of oscillations, as well as the duration of processing, the increase in moisture in the grain increases nonlinearly. With oscillation amplitudes of 10 and 20 mm and constant frequency of 10 Hz and processing duration of 8 min., Wheat grain increased moisture by 2.1%. Processing time more than 8 min. does not increase the moisture content of wheat. The largest increase in moisture in wheat was observed at an oscillation frequency of 12 Hz and an amplitude of 20 mm and a treatment duration of 5 min. Increasing the oscillation frequency more than 12 Hz did not lead to an increase in wheat moisture. It was found that the load does not affect the efficiency of moistening wheat grain.

12

Modification of the guitar bracing using optimization

Pilch Adam

Vibrations in Physical Systems

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2023

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Vol. 34, nr 2

art. no. 2023221

EN

The form of modern guitars were shaped by Spanish luthiers in the XIX century. Especially Antonio de Torres Jurado is the one, whose designs are an inspiration for modern constructions. From the very beginning, guitars are struggling with not sufficient sound levels for all the desired applications. Apart from electroacoustic amplification, there were several attempts to modify the construction of the sound hole or the soundboard. Higher sound pressure levels were often connected with distorted sound, sometimes not acceptable to musicians. In this paper, inequalities in the frequency characteristics of the sound generated by the guitar with modern sound holes are presented. Resonant frequencies of the soundboard were pointed as being responsible for the too high amplitude of sound in the 600-800 Hz frequency range. Using optimization and finite element method modelling, the best patterns of bracings were proposed to equalize the frequency spectrum and improve the sound of the instrument.

13

Research of the energy parameters of the vibro-ozonation complex

Tsurkan Oleh, Prysiazhniuk Dmytro, Spirin Anatolii, Borysiuk Dmytro, Tverdokhlib Ihor, Hrushetskyi Serhii

Przegląd Elektrotechniczny

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2023

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R. 99, nr 6

39--44

EN

In the system of technological operations of post-harvest processing of grain, the most important place belongs to drying. High-quality drying not only ensures the storage of the harvested crop, prevents its loss, but in some cases also improves the quality of the finished product. It is at this stage that up to 80% of all the energy of the post-harvest processing of grain is spent, and the useful use of energy in the grain dryers is up to 40…45%. The direction of improvement of grain drying technologies is: reduction of energy costs for moisture removal, ensuring environmental safety of the dried product, development of highly efficient grain drying equipment. A significant intensification of the grain drying process can be achieved by using the vibration effect on the processed material with simultaneous treatment with ozone as part of the drying agent, which additionally reduces the energy costs of the operation and allows obtaining a high-quality final material. The energy parameters of the developed vibro-ozonation complex, depending on the mode parameters of the studied process of drying grain raw materials, were experimentally investigated in the article.

PL

W systemie operacji technologicznych pozbiorczej obróbki ziarna najważniejsze miejsce zajmuje suszenie. Wysokiej jakości suszenie nie tylko zapewnia przechowywanie zebranego plonu, zapobiega jego utracie, ale w niektórych przypadkach poprawia również jakość gotowego produktu. To właśnie na tym etapie zużywa się do 80% całej energii na pozbiorczą obróbkę ziarna, a użyteczne wykorzystanie energii w suszarniach zbożowych sięga 40…45%. Kierunkiem doskonalenia technologii suszenia ziarna jest: obniżenie kosztów energii na odwilgocenie, zapewnienie bezpieczeństwa ekologicznego suszu, rozwój wysokowydajnych urządzeń do suszenia ziarna. Znaczne zintensyfikowanie procesu suszenia ziarna można uzyskać poprzez wykorzystanie efektu wibrowania obrabianego materiału przy jednoczesnym działaniu ozonu jako składnika suszenia, co dodatkowo obniża koszty energetyczne operacji i pozwala na uzyskanie wysokiej jakości materiału końcowego . W artykule zbadano eksperymentalnie parametry energetyczne opracowanego kompleksu wibro-ozonowania w zależności od parametrów modowych badanego procesu suszenia surowców zbożowych.

14

Influence of mechanical factors on the performance and aging process of oil pump jack

Aliyev Alesker M., Aliyeva Sevda Y.

Nafta-Gaz

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2023

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R. 79, nr 12

776--785

EN

The paper discusses the influence of mechanical factors on the performance and aging process of rocking machines, specifically focusing on oilfield equipment such as the downhole rod pump jack. The authors emphasize the importance of analyzing the condition and aging process of oilfield equipment to ensure reliability, safety, and efficiency in oil production processes. The mechanical factors discussed in the paper include vibrations, loads, wear, and corrosion. Vibrations can be caused by improper balance, bearing failures, or other factors, and they have a negative impact on equipment performance and can lead to breakdowns. High mechanical loads associated with raising and lowering sucker rods can cause wear and damage to the pump jack. Operating in harsh environments with sand, abrasive particles, or chemicals can also cause wear on surfaces and equipment parts. Corrosion of metal components can occur due to moisture, chemical attack, or improper storage and maintenance, leading to deterioration and breakage of equipment. The consequences of these mechanical factors on the aging of an oil pump jack include accelerated aging, decreased performance, and an increased risk of accidents. Continuous exposure to vibration, stress, wear, and corrosion accelerates the aging process, resulting in deterioration and reduced equipment life. Damage and breakdowns caused by mechanical factors lead to decreased efficiency, negatively impacting oil production processes. Moreover, insufficient maintenance and failure to address mechanical influences increase the risk of accidents, downtime, and damage to other parts of the manufacturing process. To assess the health and aging status of an oil pump jack, various analysis and diagnostic methods are used, including visual inspection, strength testing, monitoring of parameters, and non-destructive testing. Visual inspection helps identify visible damage, wear, and defects. Strength testing evaluates the reliability of pump jack parts and identifies potential issues. Monitoring parameters like vibrations, temperature, and pressure allows for detecting deviations from normal operation and preventing breakdowns. Non-destructive testing methods such as ultrasonic testing, magnetic particle testing, and radiography help identify hidden defects and damage. The authors recommend several strategies to maintain the reliability and efficiency of an oil pump jack. These strategies include implementing a preventive maintenance program with regular inspection, testing, and parts replacement based on manufacturer’s recommendations and equipment condition analysis. Determining optimal service and part replacement intervals based on historical data, monitoring results, and manufacturer’s recommendations is crucial. Additionally, utilizing more durable materials, anti-corrosion coatings, improved designs, and technologies can increase equipment resistance to mechanical stress and improve performance. The paper also describes the device and components of a pump jack, such as the installation base, platform, balancer, electric motor, crank, connecting rod, and control station. It emphasizes the importance of considering various characteristics when selecting and evaluating the effectiveness of a pump jack, including working load, maximum plunger stroke, reducer dimensions, output torque, and swing frequency. The kinematics of the pump jack drive system are discussed, highlighting the need for reconfiguration to adapt to changing operating conditions and optimize oil production performance. Overall, the paper emphasizes the importance of analyzing mechanical factors, managing the aging process, and implementing maintenance strategies to ensure the reliable and efficient operation of oilfield equipment, specifically the pump jack used in oil production processes.

PL

: W artykule omówiono wpływ czynników mechanicznych na wydajność i proces starzenia się kiwonów, koncentrując się na urządzeniach do eksploatacji złóż ropy naftowej. Autorzy podkreślają znaczenie analizy stanu i procesu starzenia się sprzętu naftowego dla zapewnienia niezawodności, bezpieczeństwa i wydajności procesów produkcji ropy naftowej. Czynniki mechaniczne omówione w artykule obejmują drgania, obciążenia, zużycie i korozję. Drgania mogą być wywołane przez nieodpowiednie zbalansowanie, usterki łożysk lub inne czynniki i mają negatywny wpływ na wydajność sprzętu oraz mogą prowadzić do awarii. Wysokie obciążenia mechaniczne powiązane z podnoszeniem i opuszczaniem żerdzi pompowych mogą powodować zużycie i uszkodzenie kiwona. Praca w trudnych środowiskach z piaskiem, cząstkami ścierającymi lub chemikaliami może także skutkować zużyciem powierzchni i części sprzętu. Korozja komponentów metalowych może wystąpić w związku z wilgocią, agresywnością chemiczną lub nieodpowiednim przechowywaniem i konserwacją i doprowadzić do degradacji i uszkodzeń sprzętu. Konsekwencje tych czynników mechanicznych względem starzenia się kiwona obejmują przyspieszone starzenie, zmniejszoną wydajność i zwiększone ryzyko wypadków. Stałe narażenie na drgania, naprężenie, zużycie i korozję przyspiesza proces starzenia, powodując degradację i zmniejszenie żywotności sprzętu. Uszkodzenia i awarie wywołane przez czynniki mechaniczne prowadzą do zmniejszenia wydajności, wpływając negatywnie na procesy produkcji ropy naftowej. Ponadto niewystarczająca konserwacja i brak uwzględnienia wpływów mechanicznych zwiększają ryzyko wypadków, przestoju i uszkodzenia innych elementów procesu produkcyjnego. Aby ocenić stan i status starzenia się kiwona, stosuje się różne analizy i metody diagnostyczne, w tym inspekcję wizualną, próby wytrzymałościowe, monitorowanie parametrów i próby nieniszczące. Inspekcja wizualna pomaga zidentyfikować widoczne uszkodzenia, zużycie i defekty. Próby wytrzymałościowe oceniają niezawodność części kiwona i identyfikują potencjalne problemy. Monitorowanie parametrów takich jak drgania, temperatura i ciśnienie pozwala wykryć odchylenia od normalnej pracy i zapobiec awariom. Metody prób nieniszczących, takie jak badania ultradźwiękowe, badania magnetyczno-proszkowe i radiografia, pomagają odnaleźć ukryte defekty i uszkodzenia. Autorzy rekomendują kilka strategii dla zachowania niezawodności i wydajności kiwona. Strategie te obejmują wdrożenie zapobiegawczego programu konserwacji z regularnymi przeglądami, testami i wymianą części na podstawie rekomendacji producenta i analizy stanu sprzętu. Kluczowe jest ustalenie optymalnych przedziałów serwisowania i wymiany części, opierając się na danych historycznych, wynikach monitoringu i rekomendacjach producenta. Dodatkowo stosowanie wytrzymalszych materiałów, powłok antykorozyjnych, ulepszonych konstrukcji i technologii może zwiększyć wytrzymałość sprzętu na naprężenia mechaniczne i poprawić wydajność. W artykule opisano także urządzenia i komponenty kiwona, takie jak podstawa instalacyjna, platforma, wahacz, silnik elektryczny, korba, żerdź łącząca i stanowisko sterowania. Podkreślono znaczenie uwzględnienia różnych cech podczas wyboru i oceny wydajności kiwona, w tym obciążenia roboczego, maksymalnego suwu tłoka, wymiarów reduktora, wyjściowego momentu obrotowego i częstotliwości ruchu wahadłowego. Omówiona została kinematyka systemu napędowego kiwona, z podkreśleniem potrzeby rekonfiguracji w celu przystosowania się do zmiennych warunków pracy i optymalizacji wydajności produkcji ropy naftowej. Ogólnie rzecz biorąc, w artykule podkreślono znaczenie analizy czynników mechanicznych, zarządzania procesem starzenia i wdrażania strategii konserwacji dla zapewnienia niezawodnej i wydajnej pracy sprzętu na złożach ropy naftowej, a konkretnie kiwona stosowanego w procesach produkcji ropy naftowej.

15

Operating characteristics of bearings with magnetic nanoparticles doped lubricant

Krenicky Tibor, Mascenik Jozef, Coranic Tomas, Ruzbarsky Juraj

Mining Machines

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2023

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vol. 41, iss. 3

168--174

EN

The main aim of the presented research was to investigate theoperational characteristics of a bearing when alternative lubricants were used for comparison with a standard lubricant, including that containing magnetic nanoparticles. The bearing was subjected to varying operating conditions, differing in terms of mechanical load status. The monitoring of the bearing operation parameters primarily focused on monitoring the velocity and acceleration of vibrations, as well as the operating temperature of the bearing. Thebearingwith lubricant doped by magnetic nanoparticles exhibited reduced vibration velocity and acceleration values both under no load conditions and when subjected to a mechanicalload. The operating temperature slightly increased during testing in the case ofthe bearing with nanoparticles compared to the bearing using the original lubricant.

16

Analysing the impact of cutting force and vibration on surface roughness in external cylindrical grinding of SKH2 steel

Hoang Long, Nguyen Linh Tuan

Journal of Machine Engineering

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2023

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Vol. 23, No. 3

130--140

EN

The surface roughness of a part during external cylindrical grinding is directly impacted by cutting force and vibration, which are intermediate parameters. To improve the quality of finished parts, studying and controlling these parameters is essential. In this research, the Taguchi method combined with ANOVA analysis was utilized to analyse the effects of feed rate, cutting depth, and rotational speeds on cutting force and vibration amplitude. The test material used was SKH2 steel, which was heat-treated to a hardness of 60 HRC. The research aimed to investigate the relationship between cutting force, vibration, and surface roughness. The study concludes with an analysis of the influence of cutting force and vibration on the surface roughness of parts during external cylindrical grinding. The results show that as cutting force and vibration increase, the surface roughness of the workpiece in external grinding will also increase, and conversely when cutting force and vibration decrease, the surface roughness will decrease.

17

Procedury uwzględniania wpływu drgań komunikacyjnych na budynki eksploatowane

Kawecki Janusz, Tatara Tadeusz

Inżynieria i Budownictwo

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2023

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R. 79, nr 3-4

132--144

PL

Opracowanie nawiązuje do ogólnych wymagań zapisanych w "Prawie ochrony środowiska", dotyczących oceny standardów jakości środowiska odnoszących się do emisji drgań pochodzących od eksploatowanych dróg. Podano tu procedury przydatne w ocenianiu wpływu na budynki eksploatowane drgań generowanych przejazdami pojazdów w pobliżu tych budynków. Drgania takie są wymuszeniem kinematycznym budynku i mogą doprowadzać do jego uszkodzeń (rysy, uszkodzenia elementów architektonicznych, zarysowania w elementach konstrukcyjnych itp.). Z kolei drgania w budynku mogą wpływać na naruszenie warunków niezbędnego komfortu wibracyjnego. Mogą też naruszać wymagania odnoszące się do warunków pracy urządzeń wrażliwych na drgania w budynkach eksploatowanych. Zadaniem rzeczoznawcy jest opracowanie diagnozy, w wyniku której uzyskuje się informacje o tym, czy istnieje związek skutkowo-przyczynowy między naruszeniem warunków bezpiecznej eksploatacji budynku a działaniem źródła drgań. Zastosowanie procedur tu opisanych powinno ułatwić wykonanie takich diagnoz. Postępując według podanych procedur rzeczoznawca będzie stosował odpowiednie narzędzia diagnostyczne, o których niezbędne informacje również zamieszczono w niniejszym opracowaniu.

EN

The study refers to the general requirements of the Environmental Protection Law regarding the assessment of environmental quality standards relating to the emission of vibrations from the roads in use. The article discusses the useful procedures for assessing the impact of vibrations generated by passing vehicles near the buildings. Such vibrations are a kinematic excitation for the building and can lead to damage (Iike cracks, damage to architectural elements, scratches in structural elements, etc.). In turn, vibrations in the building may affect the violation of the conditions of the necessary vibration comfort. They may also violate the requirements relating to the working conditions of devices sensitive to vibrations in exploited buildings. The expert task is to develop a diagnosis, as a result of which information is obtained as to whether there is a cause-and-effect relationship between the violation of the conditions for the safe operation of the building and the operation of the source of vibration. The use of the procedures described here should facilitate such diagnoses. Following the given procedures, the expert will use appropriate diagnostic tools, and the necessary information described in this study.

18

Działalność Laboratorium Badań Konstrukcji na Wydziale Budownictwa, Inżynierii Środowiska i Architektury Politechniki Rzeszowskiej

Janas Lucjan

Inżynieria i Budownictwo

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2023

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R. 79, nr 1-2

4--8

PL

Przedstawiono zakres działalności laboratorium oraz system zarządzania wdrożony i akredytowany przez Polskie Centrum Akredytacji. Zwrócono uwagę na cele systemu oraz wynikające z tego wymagania i obowiązki. Zamieszczono wykaz procedur objętych akredytacją oraz przykłady badań wykonanych w laboratorium w ostatnich kilku latach.

EN

The scope of the laboratory's activity and the management system implemented and accredited by the Polish Centre for Accreditation were presented. Attention was drawn to the objectives of the management system and the resulting requirements and obligations. The list of procedures covered by the accreditation and examples of scientific research, carried out in the laboratory in the last few years, have been discussed.

19

Analiza numeryczna zachowania się gazociągu podziemnego w warunkach zadanych wymuszeń dynamicznych

Okroj Paweł, Hulimka Jacek

Inżynieria i Budownictwo

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2023

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R. 79, nr 11-12

599--604

PL

W artykule omówiono metodę oceny wpływów dynamicznych obciążających podziemny gazociąg w całości osadzony w podłożu gruntowym, bazującą na numerycznej analizie obliczeniowej układu grunt + gazociąg i pomiarze drgań wierzchniej płaszczyzny gruntu ponad ocenianym przewodem. Przedstawione podejście, poparte przykładowymi wynikami, jest zgodne z aktualną normą i bezpieczne - nie wymaga bowiem wykonania odkrywek w celu osadzenia czujników pomiarowych bezpośrednio na konstrukcji gazociągu.

EN

The paper discusses a method for evaluation of the dynamic loads acting on an underground gas pipeline fully embedded in the ground. The method is based on a numerical computational analysis of the soil with pipeline system and the measurement of vibrations of the top ground plane above the pipeline analysed. The approach, supported by exemplary results, complies with the current standard and is a safe alternative to direct vibration measurements which require excavating and placing measurement sensors directly on the pipeline structure.

20

Some recent developments in inerter-based devices for vibration mitigation

Wagg David J.

Bulletin of the Polish Academy of Sciences. Technical Sciences

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2023

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Vol. 71, nr 3

art. no. e144617

EN

Reducing the effect of unwanted vibrations is an important topic in many engineering applications. In this paper we describe some recent developments in the area of passive vibration mitigation. This is based on a new device called the inerter which can be exploited in a range of different contexts. In this paper we consider two recent examples; (i) where a flywheel inerter is combined with a hysteretic damper, and (ii) in which a pivoted bar inerter is developed for a machining application. In both cases, experimental test results show that the devices can outperform existing methods.