Wyniki wyszukiwania - BazTech

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Investigation of structural performance of historical Amasya Hundi Hatun Bridge

Şeker Burçin Şenol, Özkaynak Merve

Architecture Civil Engineering Environment

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2022

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Vol. 15, no. 2

109--120

EN

Bridges have been built by many civilizations throughout history to connect the two banks of a river. There have been numerous historical bridges built in Anatolian geography because the area has served as a bridge to various civilizations. This study performed a structural evaluation of the Hundi Hatun Bridge in Amasya, Turkey. First, a 3D model of the bridge was created in a digital environment, and then static and dynamic analyses were performed with software using the ANSYS Workbench finite element method. The bridge demonstrated sufficient dimensions under static loads and in the modal analysis, although the arches were subject to translational movement in the flow direction of the river. In addition, linear and nonlinear material models were used to perform dynamic analyses, including bridge seismic analyses. The linear material model indicated that the bridge is safe, while the nonlinear material model revealed that damage may occur, especially at the abutments and peak regions of the bridge. Moreover, the bridge arch flatness was determined to be a very important parameter. The results of this study can be used to guide future restoration efforts.

2

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

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2020

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Vol. 102, nr 1

16--29

EN

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.

3

Propagacja fali przyspieszenia w nieliniowym materiale sprężystym

Major M.

Zeszyty Naukowe. Budownictwo / Politechnika Śląska

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2002

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z. 95

387-396

PL

W niniejszej pracy rozważa się propagację płaskiej fali przyspieszenia w nieliniowo sprężystym materiale Zahorskiego. Na wstępie obliczono współrzędne zredukowanego tensora akustycznego i określono prędkości propagacji fal. Dalej w oparciu o wektory jednostkowe o kierunku amplitudy wyznaczono składowe promienia akustycznego.

EN

The paper considers the propagation of acceleration waves in Zahorski nonlinear elastic materials. At the first the acoustic tensor is calculated and velocity of the propagation waves is defined. Then with the aid of unit vectors in the direction of the amplitude the components of acoustic ray are determined.