Wyniki wyszukiwania - BazTech

Ograniczanie wyników

Znaleziono wyników: 3

Liczba wyników na stronie

Wyniki wyszukiwania

Wyszukiwano:
w słowach kluczowych: belki wielowarstwowe

Sortuj według:

Ogranicz wyniki do:

Concrete grade change in the layers of three-layer steel fibre reinforced concrete beams

Lam T. Q. K., Do T. M. D., Ngo V. T., Nguyen T. T. N., Pham D. Q.

Journal of Achievements in Materials and Manufacturing Engineering

2020

Vol. 102, nr 1

16--29

Purpose: Determine the state of stress-strain, formation and development cracks, three-layer beam diagrams of load-compression stress, load-tension stress, load-vertical displacement relationships with a change in concrete grade. Design/methodology/approach: This paper presents the results of an ANSYS numerical simulation analysis involving stress-strain state and cracking of the steel fiber concrete layers of three-layer reinforced concrete beams with the upper and lower layers. With a cross-section of 150x300 mm, a total span of 2200 mm and an effective length of 2000 mm, the middle is a normal concrete layer. Under two-point loads, all the beam samples were tested. The research simulated three-layer concrete beams in different layers of beams with a change in concrete grade, and compared with and without the use of steel fibers in layers of concrete beams, including the nonlinearity of the material considered. Findings: A diagram of the formation and development of cracks in three-layer concrete beams has been constructed by the study results, determining the load at which the concrete beams begin to crack, the load at which the concrete beams are damaged. In the middle of three-layer steel fiber reinforced concrete beams, load-compression stress, loadtension stress, load-vertical displacement relationships are established. Study results show that these three-layer concrete beams appear to crack earlier than in other cases in cases 2 and 3, but the beam bearing capacity is damaged at 67 kN, the earliest in case 3. And case 6 at 116 kN is the latest. The effects of case 1 and case 3 are small compared with and without the use of steel fibers in cases, while the effects of case 5 and case 6 are very high. Research limitations/implications: The research focuses only on the change of concrete grade in the layers, but the input parameters affecting three-layer steel fiber concrete beams have not been researched, such as the number of tensile steel bars, tensile steel bar diameter, steel fiber content in concrete, thickness variation in three-layer concrete beam layers, etc. Practical implications: Provides a result of experimental study and ANSYS numerical simulation in multi-layer steel fiber concrete beams. Originality/value: The analysis of multi-layered steel fiber concrete beams using experimental and simulation methods shows that other parameters influencing the beams will continue to analysis the working stages of three-layer beams.

Badania doświadczalne i analiza numeryczna utraty stateczności ściskanych belek siedmiowarstwowych

Paczos P., Jasion P., Wasilewicz P., Grygorowicz M., Wypych A.

Modelowanie Inżynierskie

2016

T. 28, nr 59

54--62

Praca przedstawia badania doświadczalne oraz analizę MES ściskanych belek siedmiowarstwowych. Belki składały się z siedmiu warstw: trzech blach trapezowych oraz czterech blach płaskich. Badano belki w dwu różnych konfiguracjach ułożenia blach trapezowych. Uzyskane wyniki pozwoliły na oszacowanie sił krytycznych dla belek o różnych długościach. Badania doświadczalne wskazały słabe i mocne strony połączeń klejonych oraz sposób realizacji przykładanego obciążenia.

In the paper experimental investigations and a finite elements analysis of seven-layered beams were presented. The beams consisted of seven layers: three trapezoidally corrugated steel sheets and four flat sheets. Two layouts of corrugated layers were considered. The obtained results were used to estimate the critical load of beams having different lengths. The experimental investigations showed advantages and disadvantages of glued connections and the used test stand, i.e. the way of applying load to beams.

Rheological redistribution of stresses in multi-layered beams

Socha T.

Civil and Environmental Engineering Reports

2010

No. 5

219-233

The paper concerns problems of rheology in wooden structures reinforced with polyester-glass composite bars glued to them by means of epoxy resin. A theoretical model of the behaviour of a multi-layered beam is presented. The component materials of this beam are described with equations for linear viscoelastic media (five- and sixparameter rheological models). The Bernoulli's plane sections hypothesis has been assumed and this assumption includes the statement that the particular layers are perfectly composed with no allowances for creep. Equations for stresses have been derived. To verify the elaborated theoretical model, a program of experimental tests has been prepared. The performed calculations have revealedthat the theoretical model is consistent with the experimental data. The redistribution of stresses occurs in the beam, also when global loads are constant in time.

W referacie przedstawiono problemy reologii konstrukcji wielowarstwowych na przykładzie belek drewnianych wzmacnianych wklejonymi prętami kompozytowymi (trzy warstwy: drewno, spoina klejowa o dużej grubości, pręt kompozytowy). Zaprezentowano teoretyczny model pracy tego typu belki zbudowany w oparciu o równania ośrodków liniowo lepkosprężystych, hipotezę płaskich przekrojów oraz założenie idealnego zespolenia elementów składowych. Wykorzystując rachunek operatorowy wyprowadzono równania ugięć i naprężeń. W celu weryfikacji modelu teoretycznego przeprowadzono badania doświadczalne na belkach w skali naturalnej, litych i wzmocnionych. Wykonane obliczenia wykazały dobrą zgodność modelu teoretycznego z danymi doświadczalnymi. Stwierdzono istotną redystrybucję naprężeń w obrębie przekroju poprzecznego.