Dynamic analysis of bridge-train interaction through wheel-rail interfaces | |
| Author | Dinh Van Nguyen |
| Call Number | AIT Diss. no.ST-09-02 |
| Subject(s) | Bridges Structural dynamics Bridge railings |
| Note | A dissertation submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy in Structural Engineering, School of Engineering and Technology |
| Publisher | Asian Institute of Technology |
| Series Statement | Dissertation ; no. ST-09-02 |
| Abstract | In this dissertation, a new three-dimensional (3-D) wheel-rail interface (WRI) considering both geometrical and equilibrium compatibilities was proposed. Formulations of 3-D bridge-train dynamic interactions through WRI were derived. An efficient numerical algorithm using staggered scheme for separately solving bridge and train subsystems and iterations for interface compatibilities was developed. A simple and explicit set of derailment assessment criteria based on relative movements of wheelset to the rails and wheel-rail contact mechanism was suggested. The WRI is realistic as its compatibilities include the equilibrium of contact forces, wheel jumps, rail irregularities and local deformations of wheel-rail contact. The vertical contact is represented by finite tensionless stiffness and the lateral contact is idealized by finite contact stiffness and creepage damping. The relative rotations of a wheel set to the rails about its vertical and longitudinal axes are included. This 3-D bridge-train interaction model is adequate, in which there are four degrees of freedom (DOFs) in a wheel set, five DOFs in each bogie or car-body. The bridge is idealized by 3-D beam elements considering eccentricities and deck displacement due to torsion. The track is ballastless slab and the rail irregularity profiles are numerically generated by random processes. Reduction techniques are introduced to make the coefficient matrices of the bridge and the train symmetric, independent of time and space, and be stored in one-dimensional arrays. Austin's extrapolation was employed to improve the train solver for low convergence cases. The modeling process and solution algorithm thus become efficient and versatile, especially for trains having a large number of cars, complex sub-structures such as long track, multi-span or cable bridges, and poor rail quality. The calculation of 3-D relative movement time histories of all train's wheels to the rail is another advantage. Performances of the WRI, interaction formulations and algorithm were proved in the two case studies of multi-car trains passing over a simply-supported bridge and a two-span continuous bridge at various speeds and rail irregularity wavelength ranges. In the case studies, resonance of the bridges due to repetitive wheel loads, behavior and acceptability of responses of the bridges, car-bodies and wheel sets, and the relations between these responses and rail irregularity wavelengths were investigated. Interesting phenomena were drawn from these relations and behavior. The extension and application of this research are open for long ballast track, railway noise, wheel-rail impact, and computerized procedures for running safety assessment |
| Year | 2009 |
| Corresponding Series Added Entry | Asian Institute of Technology. Dissertation ; no. ST-09-02 |
| Type | Dissertation |
| School | School of Engineering and Technology |
| Department | Department of Civil and Infrastucture Engineering (DCIE) |
| Academic Program/FoS | Structural Engineering (STE) /Former Name = Structural Engineering and Construction (ST) |
| Chairperson(s) | Pennung Warnitchai ;Kim, Ki-Du (Co-Chairperson); |
| Examination Committee(s) | Worsak Kanok-Nukulchai ;Park, Kyung-Ho; |
| Scholarship Donor(s) | Asian Institute of Technology Fellowship; |
| Degree | Thesis (Ph.D.) - Asian Institute of Technology, 2009 |