Field measurement and model prediction of rail corrugation

2019 ◽  
Vol 234 (4) ◽  
pp. 381-392 ◽  
Author(s):  
GX Chen ◽  
S Zhang ◽  
BW Wu ◽  
XN Zhao ◽  
ZF Wen ◽  
...  
Keyword(s):  
Finite Element ◽  
Field Test ◽  
Model Prediction ◽  
Field Measurement ◽  
The Self ◽  
Finite Element Models ◽  
Rail Corrugation ◽  
Track System ◽  
Excited Vibration ◽  
Good Agreement

In a field test, three corrugation profiles of rails and their corresponding vibrations were measured, and the wavelengths and frequencies of rail corrugations were obtained. In the model prediction, finite-element models of the self-excited vibrations corresponding to three different wheelset–track systems were established. The corrugation frequencies of these models were predicted, and a comparison between the measured and the predicted corrugation frequencies showed that they are in good agreement. It can be concluded that the self-excited vibration of a wheelset–track system can cause rail corrugation. A benchmark condition for the validation of rail corrugation models is proposed.

scholarly journals Friction-Induced Vibration of a Railway Wheelset-Track System and Its Effect on Rail Corrugation

Lubricants ◽  
2020 ◽  
Vol 8 (2) ◽  
pp. 18
Author(s):  
Guangxiong Chen
Keyword(s):  
Finite Element ◽  
Finite Element Model ◽  
Element Model ◽  
The Self ◽  
3D Finite Element ◽  
Rail Corrugation ◽  
Track System ◽  
Excited Vibration ◽  
Creep Force ◽  
Friction Induced Vibration

In the present study, the effect of the radius of railway curved tracks on the slip of a wheel on a rail is studied. A 3D finite-element model of a wheelset-track system is established when the creep force between the wheel and rail is saturated. The occurrence propensity of the self-excited vibration of the wheelset-track system is predicted. It is concluded that the radius of curved tracks has a strong effect on the slip of wheels on rails. In the tightly curved tracks, the slip of the wheel of the leading wheelset on the rail always occurs. The wheelset-track system has a strong occurrence propensity for unstable vibrations on the tightly curved tracks. The accuracy of the rail corrugation prediction based on the unstable vibrations of wheelset-track systems is determined to be 85–90% or higher.

Contribution of Gear Body to Tooth Deflections—A New Bidimensional Analytical Formula

2004 ◽  
Vol 126 (4) ◽  
pp. 748-752 ◽  
Author(s):  
P. Sainsot and ◽  
P. Velex ◽  
O. Duverger
Keyword(s):  
Finite Element ◽  
Analytical Formula ◽  
Constant Stress ◽  
Finite Element Models ◽  
Gear Dynamics ◽  
Computer Codes ◽  
Stress Variations ◽  
Tooth Pair ◽  
Good Agreement

The magnitude and variation of tooth pair compliance affects tooth loading and gear dynamics significantly. This paper presents an improved fillet/foundation compliance analysis based on the theory of Muskhelishvili applied to circular elastic rings. Assuming linear and constant stress variations at root circle, the above theory makes it possible to derive an analytical formula for gear body-induced tooth deflections which can be directly integrated into gear computer codes. The corresponding results are in very good agreement with those from finite element models and the formula is proved to be superior to Weber’s widely used equation, especially for large gears.

Pullout Performance of Self-Tapping Medical Screws

2011 ◽  
Vol 133 (11) ◽  
Author(s):  
Zhijun Wu ◽  
Sayed A. Nassar ◽  
Xianjie Yang
Keyword(s):  
Finite Element ◽  
The Self ◽  
Propagation Mode ◽  
Finite Element Models ◽  
Pullout Strength ◽  
Element Analysis ◽  
Synthetic Bone ◽  
Pilot Hole ◽  
The Finite Element Analysis ◽  
Failure Propagation

This study investigates the effect of the pilot hole size, implant depth, synthetic bone density, and screw size on the pullout strength of the self-tapping screw using analytical, finite element, and experimental methodologies. Stress distribution and failure propagation mode around the implant thread zone are also investigated. Based on the finite element analysis (FEA) results, an analytical model for the pullout strength of the self-tapping screw is constructed in terms of the (synthetic) bone mechanical properties, screw size, and the implant depth. The pullout performance of self-tapping screws is discussed. Results from the analytical and finite element models are experimentally validated.

scholarly journals Mechanics of Tubes Composed of Interlocking Building Blocks

2022 ◽  
Author(s):  
Kyle Mahoney ◽  
Thomas Siegmund
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
Load Transfer ◽  
Building Blocks ◽  
Maximum Load ◽  
Finite Element Models ◽  
Element Analysis ◽  
Internal Load ◽  
Deformation Response ◽  
Good Agreement

Topologically interlocking material (TIM) systems are composed of convex polyhedral units placed such that building blocks restrict each other's movement. Here, TIM tubes are considered as rolled monolayers of such assemblies. The deformation response of these assembled tubes under diametrical loading is considered. This investigation employs experiments on additivelymanufactured physical realizations and finite element analysis with contact interactions. The internal load transfer in topologically interlocking tubes is rationalized through inspection of the distribution of minimum principalstress. A thrust-line (TL) model for the deformation of topologically interlocking tubes is established. The model approximates the deformation response of the assembled tubes as the response of a collection of Misestrusses aligned with paths of maximum load transfer in the system. The predictions obtained with the TL-model are in good agreement with results of finite element models. Accounting for sliding between building blocks in theTL-model yields a predicted response more similar to experimental results with additively manufactured tubes.

Experimental Program for Investigating the Influence of Cladding Defects on Burst Pressure

2006 ◽  
Author(s):  
Shengjun (Sean) Yin ◽  
B. Richard Bass ◽  
Wallace J. McAfee ◽  
Paul T. Williams
Keyword(s):  
Finite Element ◽  
National Laboratory ◽  
Maximum Load ◽  
Plastic Instability ◽  
Experimental Program ◽  
Finite Element Models ◽  
Ductile Tearing ◽  
Oak Ridge ◽  
Clad Layer ◽  
Good Agreement

An experimental program was conducted by the Heavy-Section Steel Technology Program at the Oak Ridge National Laboratory (ORNL) to evaluate the structural significance of defects found in the unbacked cladding of the Davis-Besse vessel head. ORNL conducted total 13 clad burst tests with unflawed/flawed specimens. Failure pressure data from those tests indicated a high degree of repeatability for the tests performed in the clad burst program. Unflawed clad burst specimens failed around the full perimeter of the disk from plastic instability; an analytical model for plastic collapse was shown to adequately predict those results. The flawed specimens tested in the program failed by ductile tearing of the notch defect through the clad layer. Analytical interpretations that utilized 3-D finite element models of the clad burst specimens were performed for all tests. Fractographic studies were performed on failed defects in the flawed burst specimens to verify the ductile mode of failure. Comparisons of computed results from 3-D finite element models with measured gage displacement data (i.e., center-point deflection and CMOD) indicated reasonably good agreement up to the region of instability. For tests instrumented with the CMOD gage, good agreement between calculated and measured CMOD data up to the onset of instability implies that ductile tearing initiated near the maximum load and (with a small increase in load) rapidly progressed through the clad layer to produce failure of the specimen.

Finite Element Analysis and Experimental Study on the Behavior of Widened Beam Flange Connections of Steel Frame under Cyclic Loading

2011 ◽  
Vol 243-249 ◽  
pp. 948-952
Author(s):  
Hui Mao ◽  
Yan Wang ◽  
Cheng Hua Li
Keyword(s):  
Finite Element ◽  
Cyclic Loading ◽  
Finite Element Models ◽  
Ansys Software ◽  
Element Analysis ◽  
Side Plate ◽  
Skeleton Curve ◽  
Failure Patterns ◽  
Plate Connections ◽  
Good Agreement

Based on the experiments of four connections with widened beam flange section which included two arc widened beam flange connections and two welded side-plate connections specimens and one ordinary connection under cyclic loading, 3-D nonlinear finite element models were created by using ANSYS software to analyze the mechanical properties of these two types of widened beam flange connections, such as skeleton curve, ultimate load, ductility and failure mode etc. The analytical results show good agreement with those of the experiments and prove the finite models correct and applicable. According to the experimental and element analytical failure results, the PI(PEEQ Index) was introduced to investigate the plasticity development and fracture tendency at the end of the widened flange part . Furthermore, the failure patterns of widened beam flange connection were revealed.

Development of specimen-specific finite element models of human vertebrae for the analysis of vertebroplasty

2008 ◽  
Vol 222 (2) ◽  
pp. 221-228 ◽  
Author(s):  
V N Wijayathunga ◽  
A C Jones ◽  
R J Oakland ◽  
N R Furtado ◽  
R M Hall ◽  
...  
Keyword(s):  
Finite Element ◽  
Material Properties ◽  
Bulk Material ◽  
Image Data ◽  
Finite Element Models ◽  
Micro Computed Tomography ◽  
Bone Material ◽  
Automated Methods ◽  
Pmma Cement ◽  
Good Agreement

The aim of this study was to determine the accuracy of specimen-specific finite element models of untreated and cement-augmented vertebrae by direct comparison with experimental results. Eleven single cadaveric vertebrae were imaged using micro computed tomography (mCT) and tested to failure in axial compression in the laboratory. Four of the specimens were first augmented with PMMA cement to simulate a prophylactic vertebroplasty. Specimen-specific finite element models were then generated using semi-automated methods. An initial set of three untreated models was used to determine the optimum conversion factors from the image data to the bone material properties. Using these factors, the predicted stiffness and strength were determined for the remaining specimens (four untreated, four augmented). The model predictions were compared with the corresponding experimental data. Good agreement was found with the non-augmented specimens in terms of stiffness (root-mean-square (r.m.s.) error 12.9 per cent) and strength (r.m.s. error 14.4 per cent). With the augmented specimens, the models consistently overestimated both stiffness and strength (r.m.s. errors 65 and 68 per cent). The results indicate that this method has the potential to provide accurate predictions of vertebral behaviour prior to augmentation. However, modelling the augmented bone with bulk material properties is inadequate, and more detailed modelling of the cement region is required to capture the bone—cement interactions if the models are to be used to predict the behaviour following vertebroplasty.

scholarly journals Study on a Heuristic Wheelset Structure without Rail Corrugation on Sharply Curved Tracks

2021 ◽  
Vol 2021 ◽  
pp. 1-14
Author(s):  
G. M. Mei ◽  
G. X. Chen ◽  
S. Yan ◽  
R. X. Chen
Keyword(s):  
Difficult Problem ◽  
The Self ◽  
Potential Solution ◽  
Parameter Sensitivity Analysis ◽  
Active Method ◽  
Rail Corrugation ◽  
Incidence Trends ◽  
Track System ◽  
Railway Industry ◽  
Excited Oscillation

Rail corrugation on low rails of sharp railway curves is still a difficult problem to solve worldwide. Nearly all low rails of the sharp railway curves incur rail corrugation. In the present study, an active method to remedy rail corrugation was studied. From the viewpoint of the frictional self-excited oscillation of a wheelset-track system causing rail corrugation, the effect of wheelset structures on rail corrugation was studied. Three frictional self-excited oscillation models of wheelset-track systems with different wheelset structures were established, which include a heuristic wheelset structure and two being used in the railway industry. The incidence trends of the self-excited oscillations of these three wheelset-track systems were studied. It was found that the wheelset structure has an important effect on rail corrugation, and that the heuristic wheelset structure can restrain or get rid of rail corrugation. With the parameter sensitivity analysis, it was found that when the friction coefficient between the wheel and rail, rail gauge, rail cant, and sleeper span changes to some extent, the heuristic wheelset structure is robust enough to prevent rail corrugation. The proposed heuristic wheelset structure can be used as a potential solution to rail corrugation on sharply curved tracks.

Sign in / Sign up

Export Citation Format

Share Document