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Research paper thumbnail of Analytic Method for Vibration Analysis of Track Structure Induced by High-Speed Train

Sakarya University Journal of Science

Nowadays, the increase in heavy freight rail transport and high-speed train (HST) operations has ... more Nowadays, the increase in heavy freight rail transport and high-speed train (HST) operations has encouraged scientists to investigate the dynamic response of rail structures under moving load using analytically and numerically computational methods. In this study, to analyse vibration of rail structure, the rail has been modelled as continuous Euler-Bernoulli elastic beam system. The effects of some basic parameters such as track foundation elasticity modulus, rail stiffness, wheel set axle load and rail critical velocity which affect rail vibrations, on vibrations were examined in detail by considering different track foundation properties. The vibration wave amplitude increases as the train speed approaches the rail infrastructure critical speed.

Research paper thumbnail of Numerical Analysis of Dynamic Contact Forces Due to Interaction Moving Vehicles and Flexible Structures

In this study, the dynamic forces between the vehicle moving at a constant speed and the bridge c... more In this study, the dynamic forces between the vehicle moving at a constant speed and the bridge considered as flexible structure have been analyzed in terms of many parameters affecting these forces (such as structure rigidity, vehicle velocity, vehicle body mass). The vehicle model used in the study was modeled as a six-degree-of-freedom model with passenger and driver seats. The bridge beam considered as a flexible structure in the study was modeled according to the Euler-Bernoulli beam theory with simple supported boundary conditions. The equation of motion of the system is obtained by Lagrange equation after the energy equations of the vehicle and bridge interaction are obtained. The differential equations are solved by the fourth order Runge-Kutta algorithm time in the time domain. Then dynamic forces originating from vehicle bridge interaction are analyzed in terms of many parameters. In conclusion, it has been revealed that the dynamic forces formed between the vehicle and th...

Research paper thumbnail of Tip Deflection Determination of a Barrel for the Effect of an Accelerating Projectile Before Firing Using Finite Element and Artificial Neural Network Combined Algorithm

Latin American Journal of Solids and Structures, 2016

Research paper thumbnail of Dynamic response of a 120 mm smoothbore tank barrel during horizontal and inclined firing positions

Latin American Journal of Solids and Structures, 2015

In this study, the dynamic interaction between a 120 mm smoothbore tank barrel modeled as an Eule... more In this study, the dynamic interaction between a 120 mm smoothbore tank barrel modeled as an Euler-Bernoulli cantilever beam and an accelerating projectile during firing is presented. The interaction was modelled using a new FEM approach that took into account the projectile's inertia, Coriolis, and centripetal forces and the horizontal and inclined positions of the barrel. The mass, exit velocity and acceleration effects of the projectile on the dynamics of the barrel were investigated. The effects of the projectile's inertia, and Coriolis and centripetal forces were evaluated as well. Furthermore, the tip displacements at different firing angles were determined by transferring the mass, stiffness and damping matrices of the barrel with the addition of the instantaneous property matrices of the projectile from a local coordinate to the global Cartesian coordinate with the aid of transformation matrices. Finally, the barrel vibrations caused by the successive firings were evaluated under different firing scenarios. To demonstrate the validity of the current study, comparisons were made with the results of previous studies and a good agreement was achieved. By using the method recommended in this study, it is possible to determine the accurate dynamic behavior of any barrel with sufficient sensitivity, without any costly or time-consuming tests being necessary.

Research paper thumbnail of Optimization of a passive vibration absorber for a barrel using the genetic algorithm

Expert Systems with Applications, 2015

The non-linear vibrations of a barrel, induced by the interaction with a high-speed moving projec... more The non-linear vibrations of a barrel, induced by the interaction with a high-speed moving projectile, negatively affect the shooting accuracy of a weapon. This study presents a new method that determines the non-linear behavior of the barrel with a passive vibration absorber and optimizes the absorber using the genetic algorithm (GA). Since both the barrel geometry and its coupling with the absorber are nonlinear, a new finite element method (FEM) approximation has been developed for the interaction of barrel and projectile and combined with the classical finite element method. The final coupled equation of motion of entire system has been solved by a step by step integration, and for minimum tip deflection of the barrel, a GA has been then used in order to optimize the some parameters of the absorber. The results of analyses of the proposed FEM model were compared, and a good agreement was seen with the existing literature. In another example, the FEM-GA integrated optimization procedure was also used for the optimization of a passive vibration absorber, and a more accurate result (0.5% better) was obtained when compared to the experimental study given in literature.

Research paper thumbnail of Dynamic Response and Fuzzy Control of Half-Car High-Speed Train and Bridge Interaction

Academic Perspective Procedia, 2020

In this study, the interaction between 10-DOF half-car high-speed train (HST) and bridge has been... more In this study, the interaction between 10-DOF half-car high-speed train (HST) and bridge has been introduced with active suspension system (ASS) placed on primary and secondary system of the HST. The bridge has been modelled according to Euler-Bernoulli beam theory considering simple-supported boundary conditions. The train model consists of front and rear bogies, body masses. To connect any mass to each other the spring and damping element have been used. The equation of motion of the entire system has been determined using Lagrange equation in the time domain. The excessive vibration due to train bridge interaction (TBI) is analyzed then fuzzy logic control algorithm has been designed to control these uncomfortable vibrations. Consequently, the vibrations on the train body, front and rear bogie is reduced significantly.

Research paper thumbnail of Dynamic Vehicle and Rigid Road Interaction Analysis and Vibration Control of the Quarter Car Model Using Adaptive Neuro Fuzzy Algorithm

Academic Perspective Procedia, 2021

In this study 3-DOF quarter car model with the three bumps on the rigid road, the assumption has ... more In this study 3-DOF quarter car model with the three bumps on the rigid road, the assumption has been modeled with the non-random irregularity. To reduce the excessive vibrations occurred on the vehicle body, an active suspension system with the linear actuator has been considered. Moreover, to control this actuator, an adaptive neuro-fuzzy algorithm is designed. The training and testing data of the ANFIS has been obtained from Proportional Integral Derivative (PID) control algorithm. After that the successful training process, a testing procedure has been applied to ANFIS for the measure of the adaptive neuro-fuzzy system with data that are not considered in the training process. Then, the performance of the ANFIS is compared by the PID algorithm and passive suspension system in terms of vehicle body vertical acceleration, vehicle body vertical displacement, and control force. The road model used in the study has been modeled according to non-random road profile mathematical formul...

Research paper thumbnail of Analytic Method for Vibration Analysis of Track Structure Induced by High-Speed Train

Sakarya University Journal of Science

Nowadays, the increase in heavy freight rail transport and high-speed train (HST) operations has ... more Nowadays, the increase in heavy freight rail transport and high-speed train (HST) operations has encouraged scientists to investigate the dynamic response of rail structures under moving load using analytically and numerically computational methods. In this study, to analyse vibration of rail structure, the rail has been modelled as continuous Euler-Bernoulli elastic beam system. The effects of some basic parameters such as track foundation elasticity modulus, rail stiffness, wheel set axle load and rail critical velocity which affect rail vibrations, on vibrations were examined in detail by considering different track foundation properties. The vibration wave amplitude increases as the train speed approaches the rail infrastructure critical speed.

Research paper thumbnail of Numerical Analysis of Dynamic Contact Forces Due to Interaction Moving Vehicles and Flexible Structures

In this study, the dynamic forces between the vehicle moving at a constant speed and the bridge c... more In this study, the dynamic forces between the vehicle moving at a constant speed and the bridge considered as flexible structure have been analyzed in terms of many parameters affecting these forces (such as structure rigidity, vehicle velocity, vehicle body mass). The vehicle model used in the study was modeled as a six-degree-of-freedom model with passenger and driver seats. The bridge beam considered as a flexible structure in the study was modeled according to the Euler-Bernoulli beam theory with simple supported boundary conditions. The equation of motion of the system is obtained by Lagrange equation after the energy equations of the vehicle and bridge interaction are obtained. The differential equations are solved by the fourth order Runge-Kutta algorithm time in the time domain. Then dynamic forces originating from vehicle bridge interaction are analyzed in terms of many parameters. In conclusion, it has been revealed that the dynamic forces formed between the vehicle and th...

Research paper thumbnail of Tip Deflection Determination of a Barrel for the Effect of an Accelerating Projectile Before Firing Using Finite Element and Artificial Neural Network Combined Algorithm

Latin American Journal of Solids and Structures, 2016

Research paper thumbnail of Dynamic response of a 120 mm smoothbore tank barrel during horizontal and inclined firing positions

Latin American Journal of Solids and Structures, 2015

In this study, the dynamic interaction between a 120 mm smoothbore tank barrel modeled as an Eule... more In this study, the dynamic interaction between a 120 mm smoothbore tank barrel modeled as an Euler-Bernoulli cantilever beam and an accelerating projectile during firing is presented. The interaction was modelled using a new FEM approach that took into account the projectile's inertia, Coriolis, and centripetal forces and the horizontal and inclined positions of the barrel. The mass, exit velocity and acceleration effects of the projectile on the dynamics of the barrel were investigated. The effects of the projectile's inertia, and Coriolis and centripetal forces were evaluated as well. Furthermore, the tip displacements at different firing angles were determined by transferring the mass, stiffness and damping matrices of the barrel with the addition of the instantaneous property matrices of the projectile from a local coordinate to the global Cartesian coordinate with the aid of transformation matrices. Finally, the barrel vibrations caused by the successive firings were evaluated under different firing scenarios. To demonstrate the validity of the current study, comparisons were made with the results of previous studies and a good agreement was achieved. By using the method recommended in this study, it is possible to determine the accurate dynamic behavior of any barrel with sufficient sensitivity, without any costly or time-consuming tests being necessary.

Research paper thumbnail of Optimization of a passive vibration absorber for a barrel using the genetic algorithm

Expert Systems with Applications, 2015

The non-linear vibrations of a barrel, induced by the interaction with a high-speed moving projec... more The non-linear vibrations of a barrel, induced by the interaction with a high-speed moving projectile, negatively affect the shooting accuracy of a weapon. This study presents a new method that determines the non-linear behavior of the barrel with a passive vibration absorber and optimizes the absorber using the genetic algorithm (GA). Since both the barrel geometry and its coupling with the absorber are nonlinear, a new finite element method (FEM) approximation has been developed for the interaction of barrel and projectile and combined with the classical finite element method. The final coupled equation of motion of entire system has been solved by a step by step integration, and for minimum tip deflection of the barrel, a GA has been then used in order to optimize the some parameters of the absorber. The results of analyses of the proposed FEM model were compared, and a good agreement was seen with the existing literature. In another example, the FEM-GA integrated optimization procedure was also used for the optimization of a passive vibration absorber, and a more accurate result (0.5% better) was obtained when compared to the experimental study given in literature.

Research paper thumbnail of Dynamic Response and Fuzzy Control of Half-Car High-Speed Train and Bridge Interaction

Academic Perspective Procedia, 2020

In this study, the interaction between 10-DOF half-car high-speed train (HST) and bridge has been... more In this study, the interaction between 10-DOF half-car high-speed train (HST) and bridge has been introduced with active suspension system (ASS) placed on primary and secondary system of the HST. The bridge has been modelled according to Euler-Bernoulli beam theory considering simple-supported boundary conditions. The train model consists of front and rear bogies, body masses. To connect any mass to each other the spring and damping element have been used. The equation of motion of the entire system has been determined using Lagrange equation in the time domain. The excessive vibration due to train bridge interaction (TBI) is analyzed then fuzzy logic control algorithm has been designed to control these uncomfortable vibrations. Consequently, the vibrations on the train body, front and rear bogie is reduced significantly.

Research paper thumbnail of Dynamic Vehicle and Rigid Road Interaction Analysis and Vibration Control of the Quarter Car Model Using Adaptive Neuro Fuzzy Algorithm

Academic Perspective Procedia, 2021

In this study 3-DOF quarter car model with the three bumps on the rigid road, the assumption has ... more In this study 3-DOF quarter car model with the three bumps on the rigid road, the assumption has been modeled with the non-random irregularity. To reduce the excessive vibrations occurred on the vehicle body, an active suspension system with the linear actuator has been considered. Moreover, to control this actuator, an adaptive neuro-fuzzy algorithm is designed. The training and testing data of the ANFIS has been obtained from Proportional Integral Derivative (PID) control algorithm. After that the successful training process, a testing procedure has been applied to ANFIS for the measure of the adaptive neuro-fuzzy system with data that are not considered in the training process. Then, the performance of the ANFIS is compared by the PID algorithm and passive suspension system in terms of vehicle body vertical acceleration, vehicle body vertical displacement, and control force. The road model used in the study has been modeled according to non-random road profile mathematical formul...