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1

The applicability of shape memory alloys in structures

100%

Gwoździewicz P.

Czasopismo Techniczne

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PL

The structural application of shape memory materials is relatively new. It is possible that these materials provide the unusual property of creating stress in steel bars in a thermomechanical way. Depending on the alloy composition and production treatment, the characteristic transformation temperatures as well as the mechanical properties of the material vary and this may limit its technical effectiveness. The present work is focused on the material parameters from the point of view of practice.

2

Durability evaluation of bridge structure: comparison between analitical approach and experimental investigations

63%

Gwoździewicz P., Midro M.

Czasopismo Techniczne

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PL

The paper is focused on the problem of durability of RC structure exposed to typical ambient conditions for bridges. The causes and degradation processes of the structures, mechanisms of concrete carbonation and chloride penetration are described. The theoretical model which allows for the prognosis of all changes affecting construction safety in time is presented. The findings of the theoretical analysis are compared with the results of the experimental research of a viaduct in a state of an advanced degradation as well as the material samples taken from it.

3

“Shear lag” effect in box bridge cross-section – theorical approach and results of measurements in natural sc

63%

Ciurej H., Gwoździewicz P.

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PL

Geometrically non-linear stress and strain fields resulting from loads and prestressing are a specific property of box cross-sections. Their importance in the meaning of a calculation precision is evaluated in various ways by authors. Simultaneously, design of any structure – also of a box cross-section – is strictly connected with a correct evaluation of the stress level in materials, linearity of their behaviour and cracks appearance. This work is focused on the presentation of the existing theorical models describing the “shear lag” effect influence on the distribution of the local strain and stress in materials in box cross-section. The presentation is followed by their evaluation according to the agreements of their results with measurements results obtained on a real structure. PC bridge of a box cross-section, built as cantilever is the chosen example for comparison. Discussion of the scale of the effect influence completes the presentation of this work.

4

Atypical example of the reduction of the safety and durability of a typical motorway overbridge

51%

Ciurej H., Gwoździewicz P., Mazera A.

Czasopismo Techniczne

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PL

The present paper is related to the motorway overbridge, the technical state of which has been showing deficiencies related mainly to the presence of cracks. Verification of the design and construction documents was carried out prior to advanced analysis which covered the construction process with phases, loads acting in various periods of time as well as the progressing ground deformations. Conclusions drawn on the basis of the analysis results are not typical because the emergency situation is resulting from many simultaneously acting factors. The level of the reduction of the safety margin of the bridge has been estimated.

5

Accounting for time-dependent effects in the construction stage FEM analysis of composite pre-stressed bridge girders

51%

Gwoździewicz P., Jarno Ł., Pamin J.

Czasopismo Techniczne

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PL

In this paper, the results of the numerical analysis of pre-stressed concrete girders made of a high-strength concrete composite with a slab made of normal concrete are presented. A FEM analysis of the construction stage considering the influence of rheological effects on the behaviour of the structure was performed. Results of the analysis are presented in the work and are compared with the results of numerical analysis of the same elements, in which the time-dependent effects are not included. On the basis of these results, appropriate conclusions are proposed.

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5 Czasopismo Techniczne

3 2016

2 2015

5 Gwoździewicz P.

2 Ciurej H.

1 Jarno Ł.

1 Mazera A.

1 Midro M.

1 Pamin J.

The applicability of shape memory alloys in structures

Durability evaluation of bridge structure: comparison between analitical approach and experimental investigations

“Shear lag” effect in box bridge cross-section – theorical approach and results of measurements in natural sc

Atypical example of the reduction of the safety and durability of a typical motorway overbridge

Accounting for time-dependent effects in the construction stage FEM analysis of composite pre-stressed bridge girders