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Tytuł:
Design and Verification of Sector Vortex Archimedean Spiral Phased Array Transducer for Improving Focus Acoustic Pressure
Autorzy:
Lu, Xiaodan
Zeng, Deping
Powiązania:
https://bibliotekanauki.pl/articles/31339756.pdf
Data publikacji:
2024
Wydawca:
Polska Akademia Nauk. Czasopisma i Monografie PAN
Tematy:
phased array transducer
Archimedean spiral
high-intensity focused ultrasound
HIFU
focal deflection
Opis:
The emergence of high-intensity focused ultrasound applications brings great potential to establish noninvasive therapeutic treatment in place of conventional surgery. However, the development of ultrasonic technology also poses challenges to the design and manufacture of high-power ultrasound transducers with sufficient acoustic pressure. Here, the design of a sector vortex Archimedean spiral phased array transducer that is able to enhance focal acoustic pressure is proposed by maximizing the filling factor of the piezoelectric array. The transducer design was experimentally verified by hydrophone measurements and matched well with acoustic simulation studies. The focal deflection was shown to be feasible up to ±9 mm laterally and up to ±20 mm axially, where the effective focal acoustic pressure can be maintained above 50% and the level of the grating lobe below 30%. Furthermore, a homogeneous pressure distribution without secondary focus was observed in the pre-focal region of the transducer. The rational design of a high-intensity focused ultrasound transducer indicates promising development in the treatment of deep tissue thermal ablation for clinical applications.
Źródło:
Archives of Acoustics; 2024, 49, 1; 73-81
0137-5075
Pojawia się w:
Archives of Acoustics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A new method for generating virtual models of nonlinear helical springs based on a rigorous mathematical model
Autorzy:
Michalczyk, Krzysztof
Warzecha, Mariusz
Baran, Robert
Powiązania:
https://bibliotekanauki.pl/articles/30148247.pdf
Data publikacji:
2023
Wydawca:
Polskie Towarzystwo Promocji Wiedzy
Tematy:
helical spring
spring design
spring stiffness
load-deflection curve
spring geometry
Opis:
This paper presents a new method for generating nonlinear helical spring geometries based on a rigorous mathematical formulation. The model was developed for two scenarios for modifying a spring with a stepped helix angle: for a fixed helix angle of the active coils and for a fixed overall height of the spring. It allows the development of compression spring geometries with non-linear load-deflection curves, while maintaining predetermined values of selected geometrical parameters, such as the number of passive and active coils and the total height or helix angle of the linear segment of the active coils. Based on the proposed models, Python scripts were developed that can be implemented in any CAD software offering scripting capabilities or equipped with Application Programming Interfaces. Examples of scripts that use the developed model to generate the geometry of selected springs are presented. FEM analyses of quasi-static compression tests carried out for these spring models showed that springs with a wide range of variation in static load-deflection curves, including progressive springs with a high degree of nonlinearity in characteristics, can be obtained using the proposed tools. The obtained load-deflection curves can be described with a high degree of accuracy by power function. The proposed method can find applications in both machine design and spring manufacturing.
Źródło:
Applied Computer Science; 2023, 19, 2; 96-111
1895-3735
2353-6977
Pojawia się w:
Applied Computer Science
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A study on the deflection and crack layout in a hollow slab bridge
Autorzy:
Wang, Songtao
Wang, Dawei
Powiązania:
https://bibliotekanauki.pl/articles/27312170.pdf
Data publikacji:
2023
Wydawca:
Polska Akademia Nauk. Czasopisma i Monografie PAN
Tematy:
inżynieria mostowa
belka mostowa
belka pusta
poślizg wiązania
rozstaw pęknięć
naprężenie zbrojenia
ugięcie
bridge engineering
hollow beam
slab beam
bond-slip
crack spacing
reinforcement stress
deflection
Opis:
This paper conducts research based on the hollow slab members in the reconstruction and expansion project of expressways, two types of numerical finite element models with and without considering bond-slip relationship of reinforcement and concrete are established, and verified by tests. The distribution characteristics of crack spacing in reinforced concrete beams are studied. The results show that the bond-slip characteristics of reinforced concrete have little effect on the load-deflection characteristics of 8m hollow slab beam. Due to the influence of the bond-slip relationship of reinforced concrete, the load-deflection curve is partially serrated, while without considering the bond-slip relationship of reinforced concrete, the load-deflection curve is smooth. In the numerical model without considering the bond-slip characteristics, almost all damage occurs in the longitudinal direction, and the distribution characteristics of cracks can’t be accurately determined. Regardless of whether the bond-slip is considered or not, the macroscopic characteristics of the stress distribution is: smaller near the support and larger at the mid-span. As secondary flexural cracks expand, models with and without consideration of bond-slip characteristics can’t calculate crack spacing based on the stress distribution characteristics of the reinforcement.
Źródło:
Archives of Civil Engineering; 2023, 69, 3; 541--555
1230-2945
Pojawia się w:
Archives of Civil Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Columnar Dendrite Morphology and Solute Concentration of GH3039 Nickel-Based Superalloys during Wire and Laser Additive Manufacturing: Insights from Phase Field Simulations
Autorzy:
Zong, Nanfu
Wang, Zheng
Liu, Yang
Liang, Xinghong
Jing, Tao
Powiązania:
https://bibliotekanauki.pl/articles/2203717.pdf
Data publikacji:
2023
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
wire and laser additive manufacturing
phase field simulation
solute concentration
interface crystallographic deflection
columnar dendrite
Opis:
Wire and laser additive manufacturing (WLAM) can produce outstanding mechanical properties of GH3039 nickel-based superalloys. A quantitative rapid phase field model with solute trapping kinetics has been developed during the rapid solidification process, where a range of process conditions are considered in terms of thermal gradients and pulling speeds. Intergranular hot cracking is found to occur at boundaries of tilted columnar dendrite in the GH3039 nickel-based superalloys. The simulations demonstrate that the phase field model considering the interface deflection can represent the dendrite growth during additive manufacturing more realistically. With the aid of numerical simulations, it is determined that dendrite growth morphologies transform from symmetrical columnar dendrite to tilted columnar dendrite as the interface crystallographic deflection is increased, while increasing the deflection angle can lead to uneven composition of material matrix, especially at the columnar dendrite interface. Solute concentrations at the columnar dendrite interface tend to promote hot cracking in additively manufactured Ni-based superalloy.
Źródło:
Archives of Metallurgy and Materials; 2023, 68, 1; 387--393
1733-3490
Pojawia się w:
Archives of Metallurgy and Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Evaluation of the influence of the glass fiber mesh on the deflection basin parameters of a flexible pavement located in the area of mining activity
Ocena wpływu wzmocnienia siatką z włókna szklanego na wartości parametrów krzywizny czaszy ugięć dla nawierzchni podatnej poddanej oddziaływaniom górniczym
Autorzy:
Kałuża, Mateusz
Kotasiński, Mirosław
Bzówka, Joanna
Powiązania:
https://bibliotekanauki.pl/articles/27312128.pdf
Data publikacji:
2023
Wydawca:
Polska Akademia Nauk. Czasopisma i Monografie PAN
Tematy:
teren górniczy
siatka z włókna szklanego
osiadanie terenu
nawierzchnia podatna
wzmocnienie
FWD
parametr krzywizny
czasza ugięć
glass fiber mesh
mining subsidence
flexible pavement
reinforcement
terrain subsidence
deflection basin parameters
Opis:
Rehabilitation treatments applied to a local road prone to terrain subsidence from mining excavation should be designed considering cost-efficient and effective reinforcement solutions. In the analysed case, a glass-fibre mesh was applied under asphalt concrete layers in 2008, in one lane while another was left without the reinforcement. The main objective of this paper was to investigate the effectiveness of reinforcement by analysing the amount of produced on the pavement and the influence on pavement deflection. It was found that the reinforcement retracted the number of cracks, however, did not affect the bearing capacity. The influence of the applied geosynthetic was manifested in the values of the radius of curvature. The overall technical state of the road requires immediate treatment and the applied reinforcement proved obsolete because in this particular case of road located in the mining active terrain the glass fiber mesh did not prolong the life of the pavement.
Remonty oraz przebudowy dróg zlokalizowanych na obszarach występowania oddziaływań górniczych, powinny uwzględniać efektywne oraz ekonomiczne uzasadnione rozwiązania. W analizowanym przypadku na odcinku drogi powiatowej zabudowano siatkę z włókna szklanego pod warstwami bitumicznymi, podczas remontu w 2008 roku, w taki sposób, że jeden pas drogi został wzmocniony siatką, natomiast drugi pozostawiono bez wzmocnienia. Zasadniczym celem pracy było sprawdzenie efektywności wzmocnienia w zakresie redukcji uszkodzeń nawierzchni oraz wpływ na ugięcia nawierzchni i wskaźniki krzywizny czaszy ugięć. Zaobserwowano wyraźny wpływ na obniżenie ilości spękań nawierzchni, jednak bez poprawy nośności drogi. W zakresie wskaźników krzywizny czaszy ugięć, wpływ wzmocnienia został zaobserwowany w wartościach promienia krzywizny (RoC). Stan techniczny jezdni kwalifikuje drogę do natychmiastowego remontu lub przebudowy. Zastosowane rozwiązanie nie wpłynęło wyraźnie na poprawę trwałości odcinka drogi, jednak przeprowadzone obserwacje stanowią interesujący wstęp do dalszych badań.
Źródło:
Archives of Civil Engineering; 2023, 69, 2; 551--569
1230-2945
Pojawia się w:
Archives of Civil Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Hydropneumatic suspension testing of a wheeled armoured personnel carrier
Autorzy:
Hryciów, Zdzisław
Rybak, Piotr
Wojciechowski, Michał
Wachowiak, Przemysław
Kalicki, Bartosz
Powiązania:
https://bibliotekanauki.pl/articles/24200841.pdf
Data publikacji:
2023
Wydawca:
Polska Akademia Nauk. Polskie Naukowo-Techniczne Towarzystwo Eksploatacyjne PAN
Tematy:
hydropneumatic suspension
polytropic process
spring characteristic
static deflection
Opis:
The purpose of this study was to determine the effect of gas pressure and temperature on the spring characteristic of a HP strut used in a wheeled armoured personnel carrier. The research was performed based on a simulation model. Data to validate the model were obtained during experimental tests. The results indicate, among other things, that the friction generated in the seals is an important source of resistance force. Comparison of the simulation results with the measured characteristics indicates a proper modelling of the strut operation. Simulation studies have indicated that it is easy to modify the required suspension parameters by adjusting the initial gas pressure. A linear effect of pressure on static deflection can be assumed. Temperature has a strong influence on the spring characteristic. When it changes, significant changes in vehicle height are observed due to the lack of a compensation system. The temperature changes are not only due to changes in ambient temperature, but also by intense heating of the HP struts caused by the vehicle moving over rough terrain.
Źródło:
Eksploatacja i Niezawodność; 2023, 25, 2; art. no. 162497
1507-2711
Pojawia się w:
Eksploatacja i Niezawodność
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Simulation of displacement of cutting tool holders used for turning
Symulacja odkształceń i odchyleń uchwytów na narzędzia skrawające stosowanych do toczenia
Autorzy:
Mautner, Viktor
Horvat, Katarina
Stoić, Marija
Stoić, Antun
Powiązania:
https://bibliotekanauki.pl/articles/31232980.pdf
Data publikacji:
2023
Wydawca:
Politechnika Rzeszowska im. Ignacego Łukasiewicza. Oficyna Wydawnicza
Tematy:
FEM
cutting tool holder
deflection
turning
MES
oprawka narzędzia skrawającego
ugięcie
toczenie
Opis:
This paper gives a comparison of the deformation and deflection of two types of tool holders used in turning processes. Comparison of the deflection and stresses has been performed on the location where the highest value of deflection can be measured i.e. on the tip of the cutting insert. Selected tool holder types (TH1 and TH2) have rectangular and polygonal shank. Tool holders were 3D modelled in SolidWorks and Autodesk Inventor software packages and exposed to the loading with ANSYS structural analysis FEM software. In FEM analysis, two elements size of the network are selected (mesh size 5 and 1 mm). The simulation was carried out for five different loading values acting on the tool holder model. Obtained results confirm lower deflections on CAPTO tool holders.
W artykule porównano odkształcenie i ugięcie dwóch typów oprawek narzędziowych stosowanych w procesach toczenia. Porównanie ugięcia i naprężeń wykonano w miejscu, w którym można zmierzyć największą wartość ugięcia, czyli na czubku płytki skrawającej. Wybrane typy oprawek narzędziowych (TH1 i TH2) mają chwyt prostokątny i wielokątny. Uchwyty narzędziowe zostały wymodelowane w 3D w pakietach oprogramowania SolidWorks i Autodesk Inventor i poddane obciążeniu za pomocą oprogramowania do analizy strukturalnej FEM ANSYS. W analizie MES wybierane są dwa rozmiary elementów sieci (rozmiar oczek 5 i 1 mm). Symulację przeprowadzono dla pięciu różnych wartości obciążeń działających na model oprawki. Uzyskane wyniki potwierdzają mniejsze naprężenia i ugięcia oprawek narzędziowych CAPTO.
Źródło:
Technologia i Automatyzacja Montażu; 2023, 2; 41-49
2450-8217
Pojawia się w:
Technologia i Automatyzacja Montażu
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Strength of a bent sandwich beam with clamped ends
Autorzy:
Kustosz, Joanna
Magnucki, Krzysztof
Goliwąs, Damian
Powiązania:
https://bibliotekanauki.pl/articles/33342991.pdf
Data publikacji:
2023-11-30
Wydawca:
Sieć Badawcza Łukasiewicz - Poznański Instytut Technologiczny
Tematy:
Deflection
Classical sandwich beam
Supports – clamped ends
Shear effect
Stresses
Opis:
The subject of the work is a symmetrical sandwich beam with clamped ends under uniformly distributed load. The system of two equilibrium equations, formulated taking into account the literature, was solved analytically. The function of the shear effect and the maximum deflection of the beam were determined. The stress state at the clamped end of the beam is described in detail. The significant influence of the shear effect on the normal stresses in the outer layers of the beam near the clamped end was indicated. Exemplary calculations were made for the adopted family of beams. Moreover, the numerical FEM model of the beam was developed and calculations were made for this adopted family of beams. A comparative analysis of the obtained results was carried out.
Źródło:
Rail Vehicles/Pojazdy Szynowe; 2023, 1-2; 3-7
0138-0370
2719-9630
Pojawia się w:
Rail Vehicles/Pojazdy Szynowe
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A method for comparison of large deflection in beams
Autorzy:
Taghipour, Yasser
Darfarin, Sara
Powiązania:
https://bibliotekanauki.pl/articles/27312406.pdf
Data publikacji:
2022
Wydawca:
Uniwersytet Zielonogórski. Oficyna Wydawnicza
Tematy:
metoda porównawcza
belka
odkształcenie
ugięcie belki
comparison method
beam
large deflection
displacement functions
strain
Opis:
The deflection analysis of beams has been recently an active area of research. The large deflection of beams refers to deflections occurring due to large displacements and small strains. This type of deflection has been one of the areas of interest in the development of beam deformation methods. The wide diversity of beam deformation methods highlights the importance of their comparison to further elucidate the properties and features of each method and determine their benefits and limitations. In this study, a new comparison model is introduced which involves three steps, instead of only comparing final results for verification in common studies. In the first step, a complete comparison is made based on the assumptions and approximations of each method of the kinematics of deformation, displacement, and strain fields. After selecting the most accurate method in the first step, the displacement functions are determined by polynomial approximation under different loading and support conditions based on the selected method. In the third step, the displacement functions are used to calculate the strains in each method. The conclusion is based on comparing the strains. This comparative model can be used as a benchmark to compare different theories of deformation analysis.
Źródło:
International Journal of Applied Mechanics and Engineering; 2022, 27, 4; 179--193
1734-4492
2353-9003
Pojawia się w:
International Journal of Applied Mechanics and Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Comprehensive Analysis of Metal Deformation Law Based on Numerical Simulation of Cold Rolling Process
Autorzy:
Yan, Zhu-Wen
Wang, Bao-Sheng
Bu, He-Nan
Li, Hao
Hong, Lei
Zhang, Dian-Hua
Powiązania:
https://bibliotekanauki.pl/articles/2106570.pdf
Data publikacji:
2022
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
3D elastic-plastic FEM
work roll deflection
lateral thickness
flatness regulation effect
rolling pressure
Opis:
Through taking the cold rolling process as the research object, the three-dimensional finite element model of the strip rolling process is established by using ANSYS/LS-DYNA software. The actual rolling product data has strong consistency with the finite element simulation results. The rolling process is dynamically simulated, and the distribution curves of important rolling parameters such as equivalent stress, control efficiency coefficient, transverse rolling pressure, lateral thickness and work roll deflection is obtained. Based on summarizing the influence of rolling parameters on rolling deformation, the research results of this paper can play an important role in the actual rolling process control. The research results have certain guiding significance for the development and optimization of the rolling control system.
Źródło:
Archives of Metallurgy and Materials; 2022, 67, 2; 623--635
1733-3490
Pojawia się w:
Archives of Metallurgy and Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Experimental and analytical approaches to the mechanical resistance of moped tire under impact
Autorzy:
Sobkowicz, Katarzyna
Obst, Maciej
Kurpisz, Dariusz
Głowiński, Sebastian
Powiązania:
https://bibliotekanauki.pl/articles/2146659.pdf
Data publikacji:
2022
Wydawca:
Politechnika Poznańska. Instytut Mechaniki Stosowanej
Tematy:
moped tire deflection
tire dynamic stiffness
tire radial deflection
tire impact loading
dynamic adhesion coefficient
odchylenie opony motorowerowej
sztywność dynamiczna opony
promieniowe odchylenie opony
obciążenie udarowe opony
współczynnik przyczepności dynamicznej
Opis:
The aspects related to the dynamic modeling of the mechanical properties of motorcycle tires following the practical application of research methods have been analyzed for many years. A test stand was constructed for the examination, and a mathematical model was proposed to calculate tire parameters. This study aims to develop the characteristics of the radial dynamic stiffness of a pneumatic tire depending on the pressure in the tire, speed of the beater simulating tire slipping onto a small obstacle lying on the road, and impact damping. The testing device was designed to simulate a sudden strike of a tire on a stiff foreign body lying on a road plane. The experiment was performed for three different values of air pressure in the tire, beater rate, and impact energy of the tested wheel. The dynamic radial stiffness of pneumatic tires decreased with increasing deformation speed and pressure. Presented in the paper research methodology can be an introduction to further, more complicated research, where will be taken into consideration factors such as wheel rotation, driving or breaking the wheel, friction, etc. The proposed methodology can be extended to assess the dynamic adhesion coefficient during tire impact loading.
Źródło:
Vibrations in Physical Systems; 2022, 33, 1; art. no. 2022105
0860-6897
Pojawia się w:
Vibrations in Physical Systems
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Mathematical Modeling of Stress in Circuit Cards Represented by Mechanical Oscillatory Systems
Autorzy:
Kovtun, Igor
Goroshko, Andrii
Petrashchuk, Svitlana
Powiązania:
https://bibliotekanauki.pl/articles/2022447.pdf
Data publikacji:
2022
Wydawca:
Stowarzyszenie Inżynierów i Techników Mechaników Polskich
Tematy:
oscillatory system
dynamic force
stress
deflection
circuit card
resonance
Opis:
The represented paper is aimed at stress calculation in circuit cards with their representation as a type of mechanical oscillatory systems in purpose of their strength assessment especially in resonance conditions. Three types of oscillatory systems are researched: single-mass; multiple mass and oscillatory system with uniformly distributed mass. In all types the cylindrical bending of circuit cards is considered to be a set of beam-strips with rectangular cross-sections so their stress calculation is performed by conventional methods applied in strength of materials and civil engineering. Mathematical model has been developed for maximal dynamic stress and deflection estimation in circuit card assemblies represented by unique oscillatory system as prismatic beam set on two oscillating supports under inertial resonance excitation generated by constant dynamic force. Comparative analysis of mathematical modeling, MatLab simulation and experimental determination of maximal dynamic stress and deflection accomplished for three types of oscillatory systems verified proximity of obtained results. Single-mass oscillatory system is proposed as equivalent to multiple mass or uniformly distributed oscillatory systems on condition of their equal mass, geometric, elastic and dissipation characteristics in resonance frequency correspondent to the main mode of oscillation, so mathematical model designed for single-mass oscillatory system is recommended for strength and stiffness assessment in engineering calculations where possible difference in determination of stress in equivalent systems can used as safety factor.
Źródło:
Advances in Science and Technology. Research Journal; 2022, 16, 1; 303-315
2299-8624
Pojawia się w:
Advances in Science and Technology. Research Journal
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Metoda szacowania natężenia prądu korozyjnego na podstawie ugięcia elementów żelbetowych
Method of estimation of corrosion current based on deflection of reinforced concrete elements
Autorzy:
Recha, Faustyn
Powiązania:
https://bibliotekanauki.pl/articles/38173613.pdf
Data publikacji:
2022
Wydawca:
Wyższa Szkoła Techniczna w Katowicach
Tematy:
korozja stali zbrojeniowej
ugięcie elementów żelbetowych
prąd korozyjny
corrosion of reinforcing steel
deflection of reinforced concrete element
corrosion current
Opis:
W pracy podjęto problematykę ugięcia elementów żelbetowych, podlegających wpływom korozji zbrojenia. Praca ma charakter w pełni teoretyczny. Skupiono się na wyprowadzeniu zależności, wiążącej gęstość natężenia prądu korozyjnego z krzywizną ugięcia. W zamyśle przedstawionej metody jest to nowy element, umożliwiający wstępne oszacowanie gęstości prądu korozyjnego w oparciu o bezinwazyjne pomiary ugięć konstrukcji.
The study takes into account the problem of deflection of reinforced concrete elements subject to the influence of reinforcement corrosion. The work is fully theoretical. The focus was on deriving the dependence linking the corrosion current density with the deflection curvature. In the concept of the presented method, it is a new element that enables preliminary estimation of the corrosion current density based on non-invasive measurements of structure deflections.
Źródło:
Zeszyty Naukowe Wyższej Szkoły Technicznej w Katowicach; 2022, 14; 57-64
2082-7016
2450-5552
Pojawia się w:
Zeszyty Naukowe Wyższej Szkoły Technicznej w Katowicach
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Multi-criteria diagnostics of historic buildings with the use of 3D laser scanning (a case study)
Autorzy:
Szymczak-Graczyk, Anna
Walczak, Zbigniew
Ksit, Barbara
Szyguła, Zdzisław
Powiązania:
https://bibliotekanauki.pl/articles/2173661.pdf
Data publikacji:
2022
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
laser scanning
diagnostics
historic buildings
limit state method
beam deflection
mycological test
skanowanie laserowe
diagnostyka
budynek historyczny
metoda stanów granicznych
ugięcie belki
test mikologiczny
Opis:
The protection and use of historic buildings is a difficult and costly task. Most often, these objects are under conservatory protection and any interference in their structure requires appropriate consent. On the other hand, conducting construction works on historic buildings carries a high risk of their damage or even destruction. Therefore, proper prior diagnostics is an extremely important factor affecting the scope and manner of works to be conducted. The paper presents the use of 3D scanning to determine the deflection of the ceiling under the Column Hall of the historic Palace, the floor of which showed elasticity, recorded during changing service loads. After identifying the places with the greatest deflections, based on data from 3D laser scanning, test holes were made and wood samples from the ceiling were taken to perform moisture content and mycological tests. An endoscopic inspection camera was inserted into test holes, providing the basis for recognizing the structure of the ceiling, i.e. arrangement of layers as well as dimensions and spacing of ceiling beams. Strength calculations were made with the limit state method resulted in the determination of the maximum permissible service load on the ceiling. The presented course of action in diagnostics of the analysed historic building may be an example of a preliminary procedure to be taken before deciding on changes in the manner of use of historic buildings or the functionalities of their individual parts.
Źródło:
Bulletin of the Polish Academy of Sciences. Technical Sciences; 2022, 70, 2; art. no. e140373
0239-7528
Pojawia się w:
Bulletin of the Polish Academy of Sciences. Technical Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Three models of a sandwich beam: bending, buckling, and free vibrations
Autorzy:
Magnucki, Krzysztof
Magnucka-Blandzi, Ewa
Wittenbeck, Leszek
Powiązania:
https://bibliotekanauki.pl/articles/38884025.pdf
Data publikacji:
2022
Wydawca:
Instytut Podstawowych Problemów Techniki PAN
Tematy:
shear deformation theory
deflection; critical load
fundamental natural frequency
Opis:
This paper is devoted to the analytical modelling of a sandwich beam. Three models of this beam are elaborated. Two nonlinear individual shear theories of deformation of a plane cross-sections are proposed. Based on Hamilton’s principle, two differential equations of motion for each model are obtained. The bending, buckling and free flexural vibration problems of the simply-supported sandwich beam considering these three models are studied. The results of these analytical investigations are presented in tables.
Źródło:
Engineering Transactions; 2022, 70, 2; 97-122
0867-888X
Pojawia się w:
Engineering Transactions
Dostawca treści:
Biblioteka Nauki
Artykuł
Wyświetlanie 1-15 z 165

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