Wyniki wyszukiwania - BazTech

1

Investigations of stress and strain state of aluminum alloys during a hot extrusion and patterns of structure and feature formation

Aghbalyan Suren G., Bagdasaryan Vazgen, Vasilyan Gayane A., Wyczółkowski Rafał

Przegląd Naukowy Inżynieria i Kształtowanie Środowiska

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2024

|

Vol. 33, No. 1

3--16

EN

This paper investigates the stress and strain state as well as formation processes of structure and features of aluminum alloys during the hot extrusion. It has been shown that during the hot extrusion the ring layers of an extruded element experience not only longitudinal and transverse deformations, but also a slip. The slip increases from inner layers to the surface layer. The tensile principal stresses and the sum of slip deformations also increase. It has been also demonstrated that at the exit of the pressing part the tensile principal stresses have different directions, forming an angle with extruder axis, which also increases towards the surface. In conclusion, it has been stated that the main radial and circumferential deformations act as restraining deformations.

2

Measurement and analysis of the performance of the PVP-20 slip detection device

Hełka Andrzej, Wall Michał

Zeszyty Naukowe. Transport / Politechnika Śląska

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2023

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z. 118

93--108

EN

One of the most critical elements ensuring the proper operation of locomotives are devices that detect and eliminate slipping, especially during the start-up of the locomotive in difficult operating conditions. Various types of slip control systems and methods are used on traction vehicles, depending on the design of a given locomotive and the assumptions made related to the functionality of a given solution. This article describes the PVP-20 type slip detection device used in many older electric locomotives. A proprietary measuring system was developed, enabling it to be connected to the locomotive circuit, to perform measurements in conditions of large disturbances and high voltages prevailing on the electric locomotive. Using this measuring system, the PVP-20 device was tested under operating conditions for the ability to detect slips. It has been shown that the described device is highly insensitive. Hence, we propose our concept for solving this problem.

3

Charakterystyka przyczepności prętów GFRP i BFRP do betonu z dodatkiem zeolitu i metakaolinitu

Urbański Marek, Woyciechowski Piotr, Szmigiera Elżbieta, Adamczewski Grzegorz, Sosnowska Edyta

Przegląd Budowlany

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2023

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R. 94, nr 11-12

121--127

PL

Porównano zależności przyczepność-poślizg oraz mechanizmy zniszczenia dla betonu z dodatkami zeolitu i metakaolinitu w obecności prętów GFRP, BFRP i stalowych. Przyczepność prętów GFRP do betonu z dodatkiem metakaolinitu była o 50% większa niż do betonu zwykłego, natomiast przyczepność do betonu z zeolitem podobna. W przypadku prętów BFRP stwierdzono wzrost przyczepności o 7% dla betonu z metakaolinitem. Pręty BFRP miały większą przyczepność w stosunku do zbrojenia stalowego. Zmiana przyczepności prętów GFRP i BFRP była stopniowa, a poślizg był kilkukrotnie większy niż prętów stalowych.

EN

Bond stress-slip relationship and failure mechanisms for concrete with additions of zeolite and metakaolin in the presence of GFRP, BFRP and steel bars were compared. The bond strength of GFRP bars to concrete with the addition of metakaolin was 50% higher than to ordinary concrete, while the bond strength to concrete with zeolite was similar. In the case of BFRP bars, an increase in bond strength by 7% was found for concrete with metakaolin. BFRP bars had greater bond strength to steel reinforcement. The change in the bond stress of the GFRP and BFRP bars was gradual and the slip was several times greater than that of the steel bars.

4

Longitudinal shear in composite deck slabs using corrugated steel sheets

Alkurayshi Hakim S. M., Jawad Adnan K., Dawood Alaa M., Hakim S. Ahmed

Przegląd Naukowy Inżynieria i Kształtowanie Środowiska

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2021

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Vol. 30, No. 3

411--423

EN

Profile deck steel sheets are used in composite deck slabs. These sheets are standard in dimensions and shapes besides they are supplied with embossments and indentations. Such sheets are not available in Iraqi markets nowadays therefore people used another type of sheets which are corrugated without embossments or indentations in very wide range. This study covers the use of such sheets in composite slabs as decks instead of standard profiled steel sheets. The study comprises testing slabs of dimensions 0.9 × 2.5 m reinforced by steel fabric mesh and rested on corrugated sheets. Two types of shear spans are selected shorter and longer to study the longitudinal shear force transmitted due to the applied loads according to the Eurocode 4. The shorter shear spans are 600, 500 and 400 mm while longer one is 800, 750 and 700 mm. The study extended to support the requirements of design equation of the Eurocode by shear bond method also known as m–k method. The evaluated values of m and k are 0.094 and 65 respectively. The result of k which plays a very important role in shear transfer is small compared to what available in literature, therefore it is recommended to make use of shear connectors in such construction or any else method.

5

Study of the two-rotor electric motor of a drive of vehicle drive wheels

Sergienko Nikolay, Kuznetsov Valeriy, Liubarskyi Borys, Pastushchina Mariia, Gołębiowski Piotr, Tkaczyk Sławomir

Archives of Transport

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2021

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Vol. 60, iss. 4

245--257

EN

In recent years, electric and hybrid vehicles have taken more and more attention due to their apparent advantages in saving fuel resources and reducing harmful emissions into the environment. Even though electric vehicles can solve the ecological problem, their operation is faced with a number of inconveniences associated with a limited driving distance from a single charge due to limited storage of energy from an independent power source and a lack of the required service and repair infrastructure. In hybrid and electric vehicles one of the main parameters is the curb weight, which affects energy consumption, vehicle speed, stability, controllability and maneuverability. In this regard, leading car manufacturers use parts with a low specific weight (non-metallic, aluminum alloys, etc.) in the design and also exclude some units from the design. Due to these technical solutions, the vehicle's operating is improved. One of the groups of parameters to be defined when designing a new electric vehicle is the parameters relating to the electric motor. The purpose of the article is determination of the mechanical characteristics of a two-rotor electric motor during magnetic flux control and assessment of the possibility of organizing the drive of the drive wheels of the vehicle. The electric motor has two mechanically independent outputs. For the study, an electrical equivalent diagram has been developed for the given two-rotor electric motor. A simulation model of the equivalent diagram has been built. Simulating the interaction processes of the rotors with the stator made it possible to obtain data for building the mechanical characteristics for each output of the electric motor. Analysis and processing of the mechanical characteristics data of the electric motors showed the conformity and the range of changes in the torque on each of the rotors when changing their slip and revolution, which are required when building algorithms for the operation of electric motor control systems as part of drives for various purposes. Analysis of the simulation results made it possible to assess the possibility of using the considered two-rotor electric motor for the drive of drive wheels in an electric and hybrid wheeled vehicle.

6

Jak obiektywnie ocenić odporność posadzki na poślizg?

Sudoł Ewa

Inżynier Budownictwa

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2020

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nr 10

58--62

7

Experimental determination of the belt transmission slip

Mascenik Jozef, Murcinkova Zuzana

Management Systems in Production Engineering

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2019

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nr 4 (27)

205--210

EN

The presented paper provides the alternative options for determining the condition of belt gear based on the testing and monitoring. In order to carry out experimental measurements, a newly developed device for testing, monitoring and diagnostics of belt drives was designed, as well as the possibility of determination of limit states by extreme loads. The designed measuring stand allows to determine the point of destruction of the belt for an extreme load. The main objective of the experimental measurement was to determine the slip of the wedge-shaped belt. The slip was evaluated by the coefficient of belt creeping and the specific belt slip by means of the measuring stand. The measurements on the proposed device can be made when the input speed from the electric motor and the transmitted torque of the belt gear are constant while the tensioning force of the belt drive is changing or the measurements can be made when the tensioning force and input speed of the belt drive are constant and the torsional moment changes. The monitoring of specified parameters for determining the belt gear slip is made by means of sensors located at predetermined locations from which data is processed by a PC. In the paper, the analytical calculation is processed, from which the values are compared with the values measured on the proposed device.

8

Theoretical and numerical analyses of an aluminium-concrete composite beam with channel shear connectors

Polus Łukasz, Szumigała Maciej

Engineering Transactions

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2019

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Vol. 67, iss. 4

535--556

EN

This paper presents a numerical simulation and a theoretical investigation of an aluminiumconcrete composite (ACC) beam subjected to bending. ACC structures are similar to steel-concrete composite (SCC) structures. However, their girders are made of aluminium instead of steel. The use of ACC structures is limited because of the lack of relevant design rules. Due to this fact the authors suggest applying the theory for SCC structures to ACC structures. In this paper, the methods for calculating the bending resistance and the stiffness of ACC beams were presented. What is more, the results from the theoretical investigation were compared with the results from the laboratory tests conducted by Stonehewer in 1962. The calculated plastic resistance moment of the ACC beam with partial shear connection was 1.2 times lower than the bending resistance from the laboratory test. The calculated stiffness was 1.1 higher than the stiffness from the laboratory test. What is more, the authors of this paper prepared two numerical models of the ACC beam. The analysed models had different types of connection between the aluminium beam and the concrete slab. In the first variant, the aluminium beam was permanently connected with the concrete slab to model full composite action. In the second variant, the aluminium beam and the concrete slab were connected using zero-length wires, the characteristics of which were taken from the laboratory test, to take slip into account. The numerical model with zero-length springs adequately captured the elastic response of the ACC beam from the laboratory test conducted by Stonehewer.

9

Odporność na poślizg posadzek

Sudoł Ewa

Builder

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2019

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R.23, nr 2

44--47

10

Entropy generation on MHD slip flow over a stretching cylinder with heat generation/absorption

Jain S., Bohra S.

International Journal of Applied Mechanics and Engineering

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2018

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Vol. 23, no. 2

413--428

EN

In the present study, we have investigated entropy generation on a magnetohydrodynamic fluid flow and heat transfer over a stretching cylinder with a porous medium in slip flow regime. A uniform heat source and radiation is also considered. Similarity transformation has been applied for making an ordinary differential equation from nonlinear governing partial differential equations. The numerical solution for the set of nonlinear ordinary differential equations has been obtained by using the fourth-order Runge-Kutta scheme together with the shooting method. The effects of pertinent parameters such as the magnetic field parameter, permeability parameter, slip parameter, Prandtl number and radiation parameter on the fluid velocity distribution, temperature distribution, entropy generation and Bejan number are discussed graphically.

11

Beam bond tests of GFRP and steel reinforcement to concrete

Szczech D., Kotynia R.

Archives of Civil Engineering

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2018

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Vol. 64, nr 4/II

243--256

EN

The paper presents research program of bond between glass fiber reinforced polymer bars and concrete in reference to the steel bars. Bond between the reinforcement and concrete is a crucial parameter governing a behaviour of reinforced concrete members and transferring of the internal forces from concrete to the reinforcement. The use of FRP bars as an equivalent reinforcement to steel in concrete structures has increased in recent years. The FRP bars are very different from steel, mainly due to much lower elasticity modulus and their anisotropic structure. Good performance of FRP reinforced concrete requires sufficient interfacial bond between bars and concrete. However, there are no specific standards referring to the surface preparation of these bars, that leads to variable bond behaviour of the composite reinforcement to the concrete. The objective of the study was to investigate the influence of variable parameters on the bond behaviour to concrete. The experimental program consisted of eighteen beam bond specimens varying in: bar diameter (12mm, 16mm, 18mm) and type of reinforcement (GFRP sand – coated and steel bars). Although the GFRP bars indicated good bond behaviour to concrete, the average bond strength was slightly lower than that of steel reinforcement of 16mm and 18 mm, while it was higher for the GFRP bars of 12mm diameter.

12

Kontakt styczny z uwzględnieniem częściowych poślizgów dla walców parabolicznych

Brzoza A., Makrenek M.

TTS Technika Transportu Szynowego

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2015

|

R. 22, nr 12

195--199, CD

PL

W artykule omówiono kontakt styczny dla walców parabolicznych. Przedstawiono rozwiązanie kontaktu stycznego z uwzględnieniem częściowych poślizgów dla znanego rozkładu naprężeń normalnych i znanej wielkości strefy styku. Prezentowane podejście jest odmienne, niż w rozwiązaniu klasycznym, w którym stosuje się teorię Hertza. Problem częściowych poślizgów sprowadza się do równań całkowych rozwiązywanych numerycznie. Przedstawione wyniki są porównywalne z klasycznym rozwiązaniem dla styku gładkich walców parabolicznych.

EN

This paper discusses tangential contact between rough parabolic cylinders. It provides a general solution to the problem of tangential contact, taking into account partial slip for a known distribution of normal stress and a known contact area. The approach differs from the classical solution, in which the Hertz theory is used. The partial slip problem was reduced to integral equations solved numerically. The results are similar to those of the classical solution for smooth parabolic cylinders.

13

Wpływ włókien celulozowych na właściwości zapraw klejowych do płytek ceramicznych

Wieczorek M., Niziurska M., Nosal K.

Prace Instytutu Ceramiki i Materiałów Budowlanych

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2015

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R. 8, nr 22

76--85

PL

W artykule określono wpływ włókien celulozowych na właściwości klejów do płytek, takich jak obniżony spływ, wydłużony czas otwarty, wysoka elastyczność czy zdolność do szybkiego wiązania i twardnienia. Wyniki badań spływu wykazały, że dodatek włókien celulozowych wydatnie zmniejsza tendencje zaprawy do spływania. Ocena właściwości roboczych zaprawy wykazała łatwiejsze mieszanie z wodą i szybszą homogenizację próbek z dodatkiem włókien celulozowych. Stwierdzono również wyraźnie łatwiejsze nakładanie na podłoże i rozprowadzanie zapraw w porównaniu do zaprawy bazowej.

EN

In the paper the influence of cellulose fibers on the properties of adhesives for tiles, such as reduced slip, extended open time, high flexibility and the ability to rapidly setting and hardening. The cellulose fibers decreases slip mortar. Mortar cellulose fiber easily miscible with water. The addition of fiber allowed to reduce the stickiness of the tools.

14

Doświadczalna analiza procesu odkształcania plastycznego tytanu αTi z wykorzystaniem równań stanu mechanicznego

Jeleńkowski J., Klimas M., Skalski K., Dyja H., Sawicki S., Babul T.

Inżynieria Powierzchni

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2015

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nr 4

72--77

PL

Mając na uwadze aplikację tytanu w organizmie człowieka [1, 2, 3], przeprowadzono próby rozdrobnienia ziaren czystego technicznie α-tytanu (αTi, Grade 4a), wykorzystując do tego celu metodę plastometryczną Gleeble. Z wykresu pełzania Ashby’ego wybrano charakterystyczny (dla wielu metali) obszar płynięcia materiału, wynikający z mechanizmu odkształcenia wraz z dominującym udziałem dyfuzji wzdłuż jąder dyslokacji. Obszar ten określony jest zakresem temperaturowym (0,3–0,5)Tm i znormalizowanym naprężeniem τ/G od 10-3 do 10-5[5]. Na tej podstawie opracowano plan eksperymentu obróbki plastycznej w zakresie temperatur 300–700⁰C, odkształcenia (0,2–0,5) i prędkości odkształcania (10-2–102)s-1. W procesie obróbki plastycznej w wymienionych warunkach możliwe jest minimalizowanie zjawisk strukturalnych kontrolowanych dyfuzją objętościową (na korzyść zjawisk kontrolowanych dyfuzją po granicach ziaren) oraz wzdłuż jąder dyslokacji umacniających materiał poprzez rozdrobnienie ziaren. Celem podjętych badań jest analiza empirycznego równania = f (σs; T; ε; Sj), (gdzie Sj – symbol parametrów strukturalnych), dla procesu obróbki plastycznej tytanu αTi z możliwością wpływania na wielkość ziarna i umożliwiającego dobór właściwości mechanicznych do określonych zastosowań. Przeprowadzone eksperymenty plastometryczne pozwolą na rozszerzenie badań w kierunku uzyskania wyników możliwych do wdrożenia do praktyki przemysłowej.

EN

Taking into consideration the application of titanium in a human body [1, 2, 3] the experiments of the disintegration of technically pure α-titanium grains (αTi, Grade 4a) were conducted with the use of Gleebe’s plastometric method. The area of material flow resulting from the deformation mechanism together with the dominating participation of diffusion along the dislocation nuclei, which is characteristic for many metals, was chosen from Ashby’s creep diagram. This area is defined by the temperature range: (0.3–0.5)Tm and by the normalised stress τ/G from 10-3 to 10-5. On this basis the plan of plastic processing experiment was worked out within the range of temperatures 300–700°C, of deformation (0.2–0.5) and of deformation rate (10-2 –102)s-1. In the process of plastic processing under the determined conditions it is possible to minimize the structural phenomena which are controlled by volumetric diffusion (for the advantage of the phenomena which are controlled by diffusion on the borders of grains) and along the dislocation of nuclei which strengthen the material thanks to grain disintegration. The aim of the undertaken research was to analyse an empirical equation: = (σs; T; ε; Sj), (where Sj is a symbol of structural parameters) for the process of plastic processing αTi with the possibility of the influence on the grain size and enabling the choice of mechanical properties according to the determined applications. The conducted plastometric experiment will enable to extend the research in the direction of gaining the results which can be practically applied in industry.

15

Badania przyczepności stali w betonie zbrojonym

Siempu R., Kumar R. P.

Cement Wapno Beton

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2015

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R. 20/82, nr 6

341--358

PL

Przydatność betonu zbrojonego jako materiału kompozytowego zależy od przyczepności zbrojenia stalowego do otuliny betonowej. Połączenie to pełni ważną rolę przy przenoszeniu naprężeń ścinających, które powstają na powierzchni rozdziału stal – beton podczas obciążenia. Zaburzenie przenoszenia naprężeń w tej strefie będzie powodowało zakłócenia procesu przenoszenia obciążenia i właściwości kompozytu. Na zachowanie się strefy przejściowej stal – beton wpływa szereg czynników, a przede wszystkim wytrzymałość na ściskanie betonu, grubość otuliny, średnica i długość zakotwienia stali zbrojeniowej, kształt elementów zbrojeniowych, zbrojenie poprzeczne, itp. W pracy przyjęto program doświadczalny zmierzający do określenia wpływu wytrzymałości betonu, średnicy prętów zbrojeniowych (12 mm i 16 mm), długości zakotwienia prętów zbrojeniowych (wielokrotności określanej współczynnikami odpowiednio 2.5; 5 i 8.3 w przypadku prętów o średnicy 12 mm oraz 9.4 w przypadku prętów o średnicy 16 mm) na kształtowanie przyczepności stal – beton. Zaprojektowano trzy klasy betonu w oparciu o mieszanki spoiwowe zawierające dodatki mineralne. Wytrzymałość przyczepności betonu do stali zmierzono metodą wyrywania („pull out”). Na podstawie wyników uzyskanych tą metodą określono wartości naprężenia niszczącego powierzchni rozdziału stal – beton, wielkość przemieszczenia, jak również energię pękania. Stwierdzono, że ze wzrostem wytrzymałości na ściskanie betonu wzrastała również wytrzymałość wiązania betonu ze stalą. Zaobserwowano, że przemieszczenie pręta w strefie przejściowej oraz energia pękania wzrastały nie tylko ze wzrostem wytrzymałości na ściskanie betonu, ale też ze średnicą i długością prętów zbrojeniowych. Na podstawie uzyskanych wyników zaproponowano wzór określający przyczepność betonu do prętów stalowych.

EN

Effectiveness of reinforced concrete as a composite element depends on the bond between reinforcing steel and encapsulating concrete. Bond plays an important role in the transfer of shear stress that develops along the steel-concrete interface upon loading. Failure of this transfer of stress will result in the failure of strain compatibility and composite action. Several factors such as compressive strength of concrete, cover to concrete, diameter of bar, embedment length of bar, type of bar, confinement of concrete etc., influence the bond performance. In the present study, a rigorous experimental program is undertaken to check the effect of concrete strength, diameter of bar (12 mm and 16 mm), embedment length of bar (2.5 times, 5 times and 8.3 times [in case of 12 mm bar], 9.4 times [in case of 16 mm bar] on the bond behavior. Three concrete classes were designed with binary addition of supplementary cementitious materials. Pull out test was chosen to evaluate the bond strength and the ultimate bond stress, ultimate slip as well as fracture energy are the parameters determined from the experiments. Based on the results obtained, it was noted that with the increase in compressive strength of concrete, there is an increase in the bond strength. It was also observed that the slip and fracture energy increased with the concrete strength, diameter and embedment length of the bar. An equation to predict the bond strength is proposed based on the experimental results.

16

Protective Footwear And The Risk Of Slipping In Older Workers – Definitions, Achievements, Recommendations

Irzmańska E.

Autex Research Journal

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2015

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Vol. 15, no. 3

181--190

EN

Foot slippage is the most widespread unforeseen event causing falls on the same level, and a potentially contributing factor to falls from height and falls to a lower level. Statistical data on the number of slip-related accidents at work show the importance of the problem of slipping and indicate the need to continuously improve preventive measures designed to reduce injuries related to slipping, tripping, and falling (STF) on the same level. It is therefore necessary to continuously and insightfully analyze the causes of falls and undertake efforts to eliminate the occurrence of slip- and trip-induced workplace accidents. The occurrence of slips and trips is primarily related to the type and quality of floor surfaces, but it also depends on the biomechanical characteristics of the lower limbs in the transitional phases of walking gait, sole material and tread, human factors such as age, weight, and motor and vision function, the ability to adapt to the floor surface conditions, as well as on a number of factors linked to the workplace environment and work organization. This problem is going to escalate as a result of the higher retirement age, due to which many persons over the age of 60 will have to continue working, often in hazardous conditions.

17

Evaluation of changes in traction properties of a drive wheel on the sod utilized by various means

Czarnecki J., Białczyk W., Brennensthul M., Cudzik A.

Agricultural Engineering

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2015

|

Vol. 19, No. 4

25--33

EN

The paper presents research results, the objective of which was to assess the traction properties of a wheel equipped with a drive tyre on sod with a varied species composition of plants and various usage level. Based on the measurements carried out with the use of a unique stand for traction research, the slip, traction force and efficiency were determined. It was proved that the species composition of sod and usage level resulted in varied values of the analysed parameters. Higher values of the traction force were obtained on sod I at the usage level of 50 and 100%. Maximum values of the traction efficiency on both sods, regardless the usage level, occurred at the wheel slip lower than 20%. In order to describe the condition of facilities, where traction research was carried out, moisture, compaction and maximum shearing stresses were measured.

PL

W pracy przedstawiono wyniki badań, których celem była ocena zmian właściwości trakcyjnych koła wyposażonego w oponę napędową na darni różniącej się składem gatunkowym roślin oraz poziomem użytkowania. Na podstawie pomiarów wykonanych przy użyciu unikatowego stanowiska do badań trakcyjnych wyznaczono poślizg oraz siłę trakcyjną i sprawność. Wykazano, że skład gatunkowy darni oraz poziom jej użytkowania skutkowały zróżnicowaniem wartości analizowanych parametrów. Wyższe wartości siły trakcyjnej uzyskano na darni I, przy użytkowaniu na poziomie 50 i 100%. Maksymalne wartości sprawności trakcyjnej na obu darniach, niezależnie od poziomu użytkowania występowały przy poślizgu koła mniejszym niż 20%.W celu scharakteryzowania stanu obiektów, na których prowadzono badania trakcyjne wykonano pomiary wilgotności i zwięzłości oraz maksymalnych naprężeń ścinających.

18

Wyznaczanie poślizgów w próbkach typu push-out techniką wizyjną

Czabak M.

Zeszyty Naukowe. Mechanika / Politechnika Opolska

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2014

|

z. 104

31-34

EN

The article presents a technique for determining slips in push-out composite wood and concrete samples by means of a digital camera. The presented analysis uses also the Matlab environment for processing the recorded images of tested samples.

19

Ceramika Majów okresu klasycznego Przedstawienia i zastosowanie

Łasisz M., Łasisz M.

Szkło i Ceramika

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2014

|

R. 65, nr 2

16--18

PL

W artykule opisano ceramikę Majów pochodzącą z okresu klasycznego (ok. 250-900 n.e.). W tym czasie rzemieślnicy tworzyli jedne z najciekawszych przykładów ceramicznego rękodzieła w prekolumbijskiej Ameryce. W artykule poruszono kwestie związane z wytwarzaniem oraz ozdabianiem naczyń. Uwagę zwrócono również na sceny namalowane na naczyniach, w których ukazano przedstawienia dotyczące społeczeństwa Majów oraz wierzeń obecnych w tej kulturze. Opisano także zastosowanie naczyń ceramicznych, które służyły w codziennym życiu, także jako dary grobowe.

EN

In the article the Maya ceramics of the Classic period (approximately A.D. 250-900) are described. During this time, the craftsmen of that people created some of the most interesting examples of ceramic crafts in pre-Columbian America. The article discusses the issues associated with the production of vessels and their decorating. Considerable attention was also paid to the scenes painted on vessels where many themes concerning Mayan society and beliefs are shown. Also described is the use of ceramic vessels that served both in everyday life and as the grave goods.

20

Ocena poślizgu w elementach zespolonych poddanych obciążeniom quasi-długotrwałym w świetle badań doświadczalnych

Furtak K.

Inżynieria i Budownictwo

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2014

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R. 70, nr 4

221--223

PL

Przedstawiono propozycję obliczania poślizgu w elementach zespolonych typu stal-beton, poddanych obciążeniom quasi-długotrwałym. Zespolenie stanowiły łączniki wiotkie. Do opisu poślizgu zaproponowano zależność s = s (P) w postaci funkcji eksponencjalnej. Puntem wyjścia był wzór do obliczania poślizgu w przypadku obciążeń doraźnych (krótkotrwałych). Wartości współczynników do tej zależności określono na podstawie wyników własnych badań doświadczalnych.

EN

The article presents analytic expressions to calculate the slip in steel-concrete composite beams subjected to quasi-permanent loads. To guarantee the composite action, flexible shear connectors in the form of shear studs are used. An easy to use expression s = s (P) in a form of exponential function is proposed to analytically describe the slip. This expr ession has been derived based on existing expression describing the slip for transient loads. The values of the coefficients in this expression, however, have been determined on the basis of the author’s experimental studies.