Search Results

You are looking at 1 - 10 of 35 items for :

  • All content x
Clear All
Pollack Periodica
Authors: Themistoklis Nikolaidis, Athanasios Michalopoulos, George Stavroulakis, and Charalampos Baniotopoulos

It has been recently proved for bridges that the collaboration between a deck structure and an external pre-stressed cable is a very advantageous structural system due to the fact that the use of external pre-stressing cables neutralizes the permanent loads. However, the action of the moving loads on the cables causes large displacements not compatible with the connected deck structure. A successful method to minimize the aforementioned undesirable displacements is to use a passive control system based on an a priori upward, vertical deformation of the deck due to the pre-stress action of the supported cables. In the present paper, a bridge model (of type MNB after Michalopoulos Nikolaidis Baniotopoulos) based on a concrete plate connected with steel beams is proposed and studied.

Restricted access

Abstract  

We prove a measure-theoretic version of a result due to Radcliffe and Scott [8] from 1999 about the reconstruction of infinite sets of real numbers. This answers their question from [8].

Restricted access

–204. Coull A., Das P.C. Analysis of curved bridge decks, Proc. Inst. Civ. Eng. Vol. 37, 1967, pp. 75–86. Das P.C. Analysis of curved bridge decks Proc

Restricted access
Pollack Periodica
Authors: Peter Michalek, Jakub Kralovanec, and Jan Bujnak

resistance under severe environments and loads. Potential use of the RPC to attach precast concrete decks to steel superstructure is studied in the paper. The shear capacity and the load-slip relations are the most important characteristics for the design of

Restricted access

derailment, and fatigue damage. To attenuate the level of this acceleration, classical solutions may be used, such as increasing the damping of the bridge or increasing its stiffness. In these circumstances, the bridge deck is damped or stiffened in order to

Open access

This paper deals with the phenomenon of track-bridge interaction in railway bridges. Due to the continuity of the rails on the structural expansion joints, the deformations of the deck might induce stresses in the rails that need to be checked. The main design criteria are now specified in Eurocode 1–2.

Restricted access

Abstract  

An automated neutron activation analysis data acquisition system has been assembled from commercially available equipment. The modifications of the components needed to make this into a working system are described in the text. The main components of the data acquisition system are a sample changer, a Ge(Li) detector, a magnetic tape deck and a minicomputer based multichannel analyzer. The sample changer has a 200-sample capacity and can handle both solid and liquid samples. Software for controlling the data acquisition system is flexible, yet simple to use. The system has operated reliably for a year and has sharply reduced the effort needed for data acquisition.

Restricted access

Abstract  

The behaviour of 66 radio-ions towards 11 exchangers and 11 solutions under standardized experimental conditions has been evaluated and classified in order to have the possibility of a rapid assessment of radiochemical separation procedures. Two systems of utilizing the bulk of data obtained have been devised and employed. The first is based on the use of a deck of cards similar to those used for fast retrieval of bibliographic information, in which the behaviour of ions is coded by means of punched holes; the second is based on the treatment of the data by means of an electronic computer. The operational modes of the two systems and examples of their practical applications are presented.

Restricted access

Equivalent unique global and local initial imperfection is introduced in standards EN 1993-1-1, EN 1999-1-1 in clause 5.3.2 (11) and in Slovak national annex to EN 1993-1-1 NB. 5. However approach described in these standards needs further explanation to fully understand its background to reduce possibility of causing errors. Equivalent unique global and local initial imperfection and derived equivalent unique global and local initial imperfection method is based on obtaining amplitude for structural buckling mode, which can be than used as full-sized imperfection in assessment of structures loaded by combination of axial compression forces and bending moments. Equivalent unique global and local initial imperfection was firstly used and introduced by prof. Eugen Chladný from Slovak University of Technology in Bratislava. The origin of this method was based on the need of assessment of upper chords of open-deck truss bridges. The main idea is described in detail by Prof. Eugen Chladný and Magdaléna Štujberová in paper in magazine Stahlbau vol. 82. Equivalent unique global and local initial imperfection method in mentioned standards and paper is designated for plane structures like simple structural members or frame structures. This paper examines in plane behavior of structures with presented imperfection and calculation procedure, which allows fast examination of many different types of plane structures.

Restricted access

( Dancy & Ritter, 2017 ) to assess value-based decision making ( Bechara et al., 1994 ). In this task, participants see four decks of cards displayed on the screen in front of them (A, B, C, and D). On each trial, participants choose a card and receive a

Open access