			Home About us Contact

Moving Vehicle (moving + vehicle)

Distribution by Scientific Domains

Engineering	100%

Selected Abstracts

Collapse of Reinforced Concrete Column by Vehicle Impact

COMPUTER-AIDED CIVIL AND INFRASTRUCTURE ENGINEERING, Issue 6 2008
Hing-Ho Tsang
The column slenderness ratio can be in the order of 6,9. Some of these buildings are right next to busy streets and hence continuously exposed to the potential hazard of a vehicle impacting on a column in an accident. In the early part of this study, the ultimate energy absorption capacity of a reinforced concrete column is compared to the kinetic energy embodied in the moving vehicle. The energy-absorption capacity is calculated from the force-displacement curve of the column as determined from a nonlinear static (push-over) analysis. The ultimate displacement of the column is defined at the point when the column fails to continue carrying the full gravitational loading. Results obtained from the nonlinear static analysis have been evaluated by computer simulations of the dynamic behavior of the column following the impact. Limitations in the static analysis procedure have been demonstrated. The effects of strain rate have been discussed and the sensitivity of the result to changes in the velocity function and stiffness of the impacting vehicle has also been studied. [source]

A modular access gateway for managing intermittent connectivity in vehicular communications

EUROPEAN TRANSACTIONS ON TELECOMMUNICATIONS, Issue 2 2006
Jörg Ott
The Drive-thru Internet architecture allows exploiting intermittent connectivity by temporarily connecting to IEEE 802.11 WLAN access points at the roadside from moving vehicles. This poses numerous challenges to a mobile user's equipment: extreme networking characteristics such as short periods of connectivity, unpredictable disconnection times, and vastly varying transmission characteristics. Heterogeneous WLAN hotspot installations may also require different authentication mechanisms and credentials. We have designed a mobile access gateway to deal with these issues on behalf of a user (group) in a moving vehicle and provide usable connectivity for applications without requiring manual operation. The gateway maximises the use of short connectivity periods by detecting network access providing signalling functions for local application processes. It also allows using dedicated radio equipment to prolong connectivity periods. Finally, in selected multi-user scenarios, further performance improvements are conceivable by sharing (non-confidential) information across users and applications. Copyright © 2005 AEIT. [source]

Moving element method for train-track dynamics

INTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN ENGINEERING, Issue 11 2003
C. G. Koh
Abstract This paper presents a new approach, called the moving element method, for the dynamic analysis of train-track systems. By discretizing the rail beam on viscoelastic foundation into elements that ,flow' with the moving vehicle, the proposed method eliminates the need for keeping track of the vehicle position with respect to the track model. The governing equations are formulated in a co-ordinate system travelling at a constant velocity, and a class of conceptual elements (as opposed to physical elements) are derived for the rail beams. In the numerical study, four cases of moving vehicle are presented taking into consideration the effects of moving load and rail corrugation. The method is shown to work for varying vehicle velocity and multiple contact points, and has several advantages over the finite element method. The numerical solutions compare favourably with the results obtained by alternative methods. Copyright © 2003 John Wiley & Sons, Ltd. [source]

A modular access gateway for managing intermittent connectivity in vehicular communications

A simple finite element model for vibration analyses induced by moving vehicles

INTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN ENGINEERING, Issue 12 2006
Shen-Haw Ju
Abstract This study developed a simple finite element method combining the moving wheel element, spring,damper element, lumped mass and rigid link effect to simulate complicated vehicles. The advantages of this vehicle model are (1) the dynamic matrix equation is symmetric, (2) the theory and formulations are very simple and can be added to a standard dynamic finite element codes easily and (3) very complicated vehicle models can be assembled using the proposed elements as simple as the traditional finite element method. The Fryba's solution of a simply supported beam subjected to a moving two-axle system was analysed to validate this finite element model. For a number of numerical simulations, the two solutions are almost identical, which means that the proposed finite element model of moving vehicles is considerably accurate. Field measurements were also used to validate this vehicle model through a very complicated finite element analysis, which indicates that the current moving vehicle model can be used to simulate complex problem with acceptable accuracy. Copyright © 2006 John Wiley & Sons, Ltd. [source]