Instrumentation and FE Analysis of a Large-Span Culvert Built under a Railway, in Finland

Studia Geotechnica Et Mechanica

2018

This paper analyses the effects of loads that change their location, i.e. moving but quasi-static loads. Displacements defining the deformation of the soil–steel structure’s shell buried in soil are calculated from the results of measurements performed using a dense grid of points located on the circumferential section of the corrugated plate. In this way, all the components of the structure, namely the corrugated plate, the backfill and the pavement with its foundation, as well as the natural (real) principles of their interaction, are taken into account in the solution. In the proposed algorithm, unit strains are converted into displacements, whereby results as accurate as the ones obtained by direct experimental measurements are obtained. The algorithm’s main advantages are that the number of points is limitless, they are regularly distributed on the circumferential section of the shell and any displacement directions can be obtained. Consequently, the deformations of the shell can be faithfully reproduced. The algorithm’s convenient feature is that one can use a simplified computational diagram of the shell in the form of a beam having the shape of the shell in 2D space (without the other components of the soil–steel structure). The advantage of this measuring method (electric resistance tensometry) is that there is no need to build the solid scaffold used for displacement measurements. The research focuses on the analysis of the displacements and the unit strains arising during the primary and secondary (return) travel of the load.

Section: Results Of Tensometric Measurementsmentioning

confidence: 99%

“…Bęben [3] and Mellat et al [4]. Moreover, static testing plays an important role in determining the mechanics of structures such as shells sunk in the soil medium, as shown previously [2,[5][6][7][8][9][10]. The influence functions used in bridge models, e.g.…”

Section: Introductionmentioning

confidence: 99%

Soil–steel structure shell displacement functions based on tensometric measurements

Studia Geotechnica Et Mechanica

2018

“…As a computational model of the soil-steel structure during its service life, a 3D model is used. [1,5,6] For the soil-steel structure during its construction, a simplified model in the form of its circumferential section, that is, a 2D model shown in Fig. 2, can be assumed.…”

Section: Effects Of Surrounding Earth On Soil-steel Structurementioning

confidence: 99%

Effects of Surrounding Earth on Shell During the Construction of Flexible Bridge Structures

Studia Geotechnica Et Mechanica

2019

A characteristic feature of soil-steel structures is that, unlike in typical bridges, the backfill and the carriageway pavement with its foundation play a major role in bearing loads. In the soil-steel structure model, one can distinguish two structural subsystems: the shell made of corrugated plates and the backfill with the pavement layers. The interactions between the subsystems are modelled as interfacial interactions, that is, forces normal and tangent to the surface of the shell. This is a static condition of the consistency of mutual interactions between the surrounding earth and the shell, considering that slip can arise at the interface between the subsystems. This paper presents an algorithm for determining the internal forces in the shell on the basis of the unit strains in the corrugated plates, and subsequently, the interfacial interactions. The effects of loads arising during the construction of a soil-steel bridge when, for example, construction machines drive over the structure, are taken into account in the analysis of the internal forces in the shell and in the surrounding earth. During construction, the forces in the shell are usually many times greater than the ones generated by service loads. Thus, the analytical results presented in this paper provide the basis for predicting the behaviour of the soil medium under operational loads.

“…The study of the effects of dynamic rail journeys distinguishes the operating speeds of heavy rail (freight) and lighter passenger trains. Separate analyses are carried out for rail vehicles adapted for high speeds [1,3,5,14,15]. Due to the scope of analyses carried out in the work on the largest impacts of vehicles, the focus was on locomotives used in acceptance tests, as shown in Figure 7.…”

Section: Dynamic Effectsmentioning

confidence: 99%

“…From the examples of studies given in many works, the influence of dynamic freight transports passing through soil and coating facilities is small. A separate problem is the behavior of these objects in the case of railway vehicles moving at high speeds [1,3,5,15]. In the case of soil-steel facilities, the problem of a passage of passenger trains adapted to high speeds (V> 160 km / h) concerns mainly the behavior of the ground center in such a construction.…”

Section: Deflection Change and Impact Line Of The Key Deflectionmentioning

confidence: 99%

The vehicle impact on the corrugated steel shell in soil-steel structures

2017

TO - PK

The paper presents the results of soil-steel structures tests under road and rail vehicles loads, which change their position alongthe track. Quasi static loads are considered in both stepping and continuous measurement method (with minimum travel speed). The impact of dynamic loads from vehicles as a function of vehicle speed was analyzed. Heavy, low-speed driving rides and as a separate group the passage of passenger trains in high speed journeys were con-si-dered. In this cases numerical simulations are performed using com-plex models of soil-steel structures. The specificity (difference) of dynamic effects from dynamic loads of rolling stock on soil-steel structures in relation to classic steel bridges is specified in the paper. The present-ed results from tests shows the favorable interaction of the railway tracks and substructures with the corrugated steel shell in the backfi lling as in the railway embankments.