Finite Element Method in Assessing Strength Properties of a Railway Surface and Its Elements

Development of railway infrastructure at the turn of the 20th and 21st centuries, as well as the speeds of trains in passenger and freight traffic are the result of improving the structure of modern rail vehicles and railway infrastructure optimization. The structure of the railway surface, which enables high speeds and transferring ever greater loads and pressures of up to 25–30 t/vehicle axis, must meet very strict strength and durability requirements. This paper discusses mathematical and numerical tools used in simulation and experimental tests of railway surfaces, as well as its selected elements. Issues addressed in this paper concern, among others, modeling of the railway track, calculations related to its static and dynamic loading, and simulation of the technological process of selected elements of railway turnout. Selected results of the simulation tests on numerical models showing their behavior under different loads are also presented in this paper. The concept of symmetry is included in the possibility of applying the method described in the article both for testing other sections of railway lines, as well as for testing other elements in which stresses occur.

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Experimental Strain Measurement Approach Using Fiber Bragg Grating Sensors for Monitoring of Railway Switches and Crossings

Sensors ◽

10.3390/s21113639 ◽

2021 ◽

Vol 21 (11) ◽

pp. 3639

Author(s):

Abdelfateh Kerrouche ◽

Taoufik Najeh ◽

Pablo Jaen-Sola

Keyword(s):

Fiber Bragg Grating ◽

Experimental Tests ◽

Cost Effective ◽

Measuring Method ◽

Bragg Grating ◽

Railway Network ◽

System Failures ◽

Railway Infrastructure ◽

Train Speed ◽

And Control

Railway infrastructure plays a major role in providing the most cost-effective way to transport freight and passengers. The increase in train speed, traffic growth, heavier axles, and harsh environments make railway assets susceptible to degradation and failure. Railway switches and crossings (S&C) are a key element in any railway network, providing flexible traffic for trains to switch between tracks (through or turnout direction). S&C systems have complex structures, with many components, such as crossing parts, frogs, switchblades, and point machines. Many technologies (e.g., electrical, mechanical, and electronic devices) are used to operate and control S&C. These S&C systems are subject to failures and malfunctions that can cause delays, traffic disruptions, and even deadly accidents. Suitable field-based monitoring techniques to deal with fault detection in railway S&C systems are sought after. Wear is the major cause of S&C system failures. A novel measuring method to monitor excessive wear on the frog, as part of S&C, based on fiber Bragg grating (FBG) optical fiber sensors, is discussed in this paper. The developed solution is based on FBG sensors measuring the strain profile of the frog of S&C to determine wear size. A numerical model of a 3D prototype was developed through the finite element method, to define loading testing conditions, as well as for comparison with experimental tests. The sensors were examined under periodic and controlled loading tests. Results of this pilot study, based on simulation and laboratory tests, have shown a correlation for the static load. It was shown that the results of the experimental and the numerical studies were in good agreement.

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Additively Manufactured Parts Made of a Polymer Material Used for the Experimental Verification of a Component of a High-Speed Machine with an Optimised Geometry—Preliminary Research

Polymers ◽

10.3390/polym13010137 ◽

2020 ◽

Vol 13 (1) ◽

pp. 137

Author(s):

Artur Andrearczyk ◽

Bartlomiej Konieczny ◽

Jerzy Sokołowski

Keyword(s):

Polymer Material ◽

High Speed ◽

Numerical Models ◽

Flow Analysis ◽

Experimental Tests ◽

Strength Analysis ◽

Compressor Wheel ◽

Operational Characteristics ◽

3D Printed ◽

Novel Method

This paper describes a novel method for the experimental validation of numerically optimised turbomachinery components. In the field of additive manufacturing, numerical models still need to be improved, especially with the experimental data. The paper presents the operational characteristics of a compressor wheel, measured during experimental research. The validation process included conducting a computational flow analysis and experimental tests of two compressor wheels: The aluminium wheel and the 3D printed wheel (made of a polymer material). The chosen manufacturing technology and the results obtained made it possible to determine the speed range in which the operation of the tested machine is stable. In addition, dynamic destructive tests were performed on the polymer disc and their results were compared with the results of the strength analysis. The tests were carried out at high rotational speeds (up to 120,000 rpm). The results of the research described above have proven the utility of this technology in the research and development of high-speed turbomachines operating at speeds up to 90,000 rpm. The research results obtained show that the technology used is suitable for multi-variant optimization of the tested machine part. This work has also contributed to the further development of numerical models.

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Numerical and experimental evaluation of masonry prisms by finite element method

Revista IBRACON de Estruturas e Materiais ◽

10.1590/s1983-41952017000200010 ◽

2017 ◽

Vol 10 (2) ◽

pp. 477-508 ◽

Cited By ~ 2

Author(s):

C. F.R. SANTOS ◽

R. C. S. S. ALVARENGA ◽

J. C. L. RIBEIRO ◽

L. O CASTRO ◽

R. M. SILVA ◽

...

Keyword(s):

Mechanical Properties ◽

Finite Element Method ◽

High Strength Concrete ◽

Numerical Models ◽

High Strength ◽

Experimental Tests ◽

Experimental Results ◽

Concrete Blocks ◽

Micro Modeling ◽

Modeling Strategy

Abstract This work developed experimental tests and numerical models able to represent the mechanical behavior of prisms made of ordinary and high strength concrete blocks. Experimental tests of prisms were performed and a detailed micro-modeling strategy was adopted for numerical analysis. In this modeling technique, each material (block and mortar) was represented by its own mechanical properties. The validation of numerical models was based on experimental results. It was found that the obtained numerical values of compressive strength and modulus of elasticity differ by 5% from the experimentally observed values. Moreover, mechanisms responsible for the rupture of the prisms were evaluated and compared to the behaviors observed in the tests and those described in the literature. Through experimental results it is possible to conclude that the numerical models have been able to represent both the mechanical properties and the mechanisms responsible for failure.

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Super-long span bridge aerodynamics: on-going results of the TG3.1 benchmark test – Step 1.2

IABSE Congress, New York, New York 2019: The Evolving Metropolis ◽

10.2749/newyork.2019.2644 ◽

2019 ◽

Author(s):

Giorgio Diana ◽

Stoyan Stoyanoff ◽

Andrew Allsop ◽

Luca Amerio ◽

Tommaso Argentini ◽

...

Keyword(s):

Numerical Models ◽

Experimental Tests ◽

Numerical Comparison ◽

Aeroelastic Stability ◽

Turbulent Wind ◽

Long Span Bridges ◽

Buffeting Response ◽

Long Span ◽

Long Span Bridge ◽

Sectional Model

<p>This paper is part of a series of publications aimed at the divulgation of the results of the 3-step benchmark proposed by the IABSE Task Group 3.1 to define reference results for the validation of the software that simulate the aeroelastic stability and the response to the turbulent wind of super-long span bridges. Step 1 is a numerical comparison of different numerical models both a sectional model (Step 1.1) and a full bridge (Step 1.2) are studied. Step 2 will be the comparison of predicted results and experimental tests in wind tunnel. Step 3 will be a comparison against full scale measurements.</p><p>The results of Step 1.1 related to the response of a sectional model were presented to the last IABSE Symposium in Nantes 2018. In this paper, the results of Step 1.2 related to the response long-span full bridge are presented in this paper both in terms of aeroelastic stability and buffeting response, comparing the results coming from several TG members.</p>

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NUMERICAL ANALYSIS OF CORRUGATED STEEL PLATE BRIDGE WITH REINFORCED CONCRETE RELIEVING SLAB

Journal of Civil Engineering and Management ◽

10.3846/13923730.2014.914092 ◽

2015 ◽

Vol 22 (5) ◽

pp. 585-596 ◽

Cited By ~ 11

Author(s):

Damian BEBEN ◽

Adam STRYCZEK

Keyword(s):

Reinforced Concrete ◽

Numerical Analysis ◽

Steel Plate ◽

Numerical Models ◽

Experimental Tests ◽

Bridge Engineering ◽

Steel Plates ◽

The Finite Element Method ◽

Calculation Results ◽

Rc Slab

The paper presents a numerical analysis of corrugated steel plate (CSP) bridge with reinforced concrete (RC) relieving slab under static loads. Calculations were made based on the finite element method using Abaqus software. Two computation models were used; in the first one, RC slab was used, and the other was without it. The effect of RC slab to deformations of CSP shell was determined. Comparing the computational results from two numerical models, it can be concluded that when the relieving slab is applied, substantial reductions in displacements, stresses, bending moments and axial thrusts are achieved. Relative reductions of displacements were in the range of 53–66%, and stresses of 73–82%. Maximum displacements and bending moments were obtained at the shell crown, and maximum stresses and axial thrusts at the quarter points. The calculation results were also compared to the values from experimental tests. The course of computed displacements and stresses is similar to those obtained from experimental tests, although the absolute values were generally higher than the measured ones. Results of numerical analyses can be useful for bridge engineering, with particular regard to bridges and culverts made from corrugated steel plates for the range of necessity of using additional relieving elements.

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Mix Design of Grade M35 by Replacement of Cement with Rice Husk Ash in Concrete

International Journal of Engineering and Management Research ◽

10.31033/ijemr.8.3.11 ◽

2018 ◽

Vol 8 (03) ◽

Author(s):

Savita Chaudhary ◽

Aditya Pratap Singh

Keyword(s):

Rice Husk ◽

Carbon Dioxide Emissions ◽

Rice Husk Ash ◽

Strength Properties ◽

Environmental Benefits ◽

Partial Replacement ◽

Pozzolanic Material ◽

Concrete Production ◽

Cement And Concrete ◽

Strength And Durability

The optimized RHA, by controlled burn or grinding, has been used as a pozzolanic material in cement and concrete. Using it provides several advantages, such as improved strength and durability properties, and environmental benefits related to the disposal of waste materials and to reduced carbon dioxide emissions. Up to now, little research has been done to investigate the use of RHA as supplementary material in cement and concrete production .The main objective of this work is to study the suitability of the rice husk ash as a pozzolanic material for cement replacement in concrete. However it is expected that the use of rice husk ash in concrete improve the strength properties of concrete. Also it is an attempt made to develop the concrete using rice husk ash as a source material for partial replacement of cement, which satisfies the

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Forecasting the impact of buildings with multi-storey underground parts on the displacement of subsoil using modern numerical tools

Studia Geotechnica et Mechanica ◽

10.2478/sgem-2021-0034 ◽

2021 ◽

Vol 0 (0) ◽

Author(s):

Hanna Michalak ◽

Paweł Przybysz

Keyword(s):

Numerical Modelling ◽

Numerical Models ◽

Deep Excavation ◽

Design And Implementation ◽

Numerical Tools ◽

Excavation Support ◽

Area Of Influence ◽

The Impact ◽

New Buildings ◽

Ground Part

Abstract The paper will analyse and review the experience to date in determining the impact range of implementation of deeply founded structures on the displacement of the subsoil in the vicinity. With the background of these experiences, primarily empirical, the present possibilities of using numerical modelling to forecast the displacements of the terrain surface in various stages of works, that is, execution of deep excavation support systems, excavation-deepening phases with successive adding of struts, construction of underground levels and erection of the above-ground part of the building, will be presented. Based on the results of own research, conclusions on the use of 3D numerical models in spatial shaping and designing the structure of underground parts of new buildings erected in dense urban development will be presented. The characterised 3D numerical models were verified, taking into account the actual results of geodetic measurements of the completed buildings. Determining the range and forecasting the displacements of the subsoil are necessary for the design and implementation of investments due to the need to ensure the safety of erection and use of a new building and the buildings located within the area of influence.

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The method of direct finite perturbation of numerical models for studying of the dynamic, stiffness and strength properties for thin-walled elements of engineering constructions.

Bulletin of Bryansk state technical university ◽

10.12737/23099 ◽

2014 ◽

Vol 2014 (4) ◽

pp. 114-124

Author(s):

Юрий Костенко ◽

Yuriy Kostenko ◽

Анатолий Чепурной ◽

Anatoliy Chepurnoy ◽

Александр Литвиненко ◽

...

Keyword(s):

Sensitivity Analysis ◽

Finite Element ◽

Natural Frequencies ◽

Numerical Models ◽

Dynamic Stiffness ◽

Strength Properties ◽

Test Problems ◽

Finite Element Models ◽

Direct Perturbation ◽

Thin Walled

The methods of direct perturbation for finite element models of thin-walled engineering constructions for sensitivity analysis of their strength, stiffness and dynamic characteristics to the change in their thickness are proposed. The approach for prediction of distribution for natural frequencies migration as result of change in their thickness are presented. The applicability of the linearized models to determine displacements, stresses and natural frequencies slightly thinned design compared to the nominal (original) are shown. The examples of test problems are given.

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Thermo-Viscoelastic Modeling of the Aircraft Tire Cornering

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1099.80 ◽

2015 ◽

Vol 1099 ◽

pp. 80-86 ◽

Cited By ~ 3

Author(s):

Iulian Rosu ◽

Lama Elias-Birembaux ◽

Frederic Lebon

Keyword(s):

Thermal Evolution ◽

Numerical Models ◽

Frictional Heating ◽

Mechanical Analysis ◽

High Speeds ◽

Numerical Studies ◽

Deformation Dynamics ◽

Viscoelastic Modeling ◽

Fully Coupled ◽

Tread Rubber

Some numerical models are proposed for simulate the aircraft tire behaviour on the ground in critical situations. Fully coupled thermo-mechanical analysis procedures taking into account finite deformation, dynamics and frictional contact are studied; the visco-elasticity properties of the rubber were identified. A good agreement is observed at moderate speed, thus the model is extrapolated to high speeds and seems able to predict results in cases for which it is not possible to obtain realistic experimental data. In order to understand the thermal evolution of tire tread rubber materials during rolling and skidding steps, new experimental and numerical studies were also realized on tire tread rubber. The aim of this approach is to simulate and understand the effect of frictional heating on the tire behaviour.

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A Probabilistic Approach for the Assessment of LOC Events in Steel Storage Tanks Under Seismic Loading

Volume 8: Seismic Engineering ◽

10.1115/pvp2018-84374 ◽

2018 ◽

Cited By ~ 2

Author(s):

Fabrizio Paolacci ◽

Daniele Corritore ◽

Antonio C. Caputo ◽

Oreste S. Bursi ◽

Bledar Kalemi

Keyword(s):

Numerical Models ◽

Simple Procedure ◽

Probabilistic Approach ◽

Seismic Loading ◽

Experimental Tests ◽

Seismic Intensity ◽

Storage Tanks ◽

Industrial Plants ◽

Damage States ◽

Relationship Of

The damage states in a storage tank subjected to seismic loading can induce loss of containment (LOC) with possible consequences (fire, explosion, etc..) both for the surrounding units and people. This aspect is particularly crucial for the Quantitative Risk Analysis (QRA) of industrial plants subjected to earthquakes. Classical QRA methodologies are based on standard LOC conditions whose frequency of occurrence is mainly related to technological accident rather than natural events and are thus useless. Therefore, it is evident the necessity of establishing new procedures for the evaluation of the frequencies of occurrence of LOC events in storage tanks when subjected to an earthquake. Consequently, in this work a simple procedure founded on a probabilistic linear regression-based model is proposed, which uses simplified numerical models typically adopted for the seismic response of above ground storage tanks. Based on a set of predetermined LOC events (e.g. damage in the pipes, damage in the nozzles, etc..), whose probabilistic relationship with the local response (stress level, etc..) derives from experimental tests, the probabilistic relationship of selected response parameters with the seismic intensity measure (IM) is established. As result, for each LOC event, the cloud analysis method is used to derive the related fragility curve.

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