Arch bridges are built since two thousand years at least. Structural materials changed during this time. The design methods were changed also. The biggest impact was noted with development of Finite Element Method and graphical methods of preparation of technical drawings which is strictly combined with development of computers. These processes appeared also in Polish construction industry, especially from the beginning of 90-ties XX century.

But in this paper we do not consider mentioned above problems. We would like to present development of arch bridges from construction technology point of view. This aspect of creation of bridge structures is not very often the subject-matter of analysis. For many investors, design engineers and contractors optimization of structures is most important issue. For most of them the reduction of volume (weight) of structural material is only solution. But sometimes it is not true – the construction technology gives much more efficient results.

We present below examples of realization in Poland medium and large span arch bridges – steel, concrete and hybrid structures.

The paper presents three methods of modelling of foundation stiffness beneath intermediate support of a 178 m long integral box girder viaduct and its impact on the values and distribution of displacements and internal forces in the pier of this support. The pier support is made of cast in situ reinforced concrete of strength class C50/60. For the analysis, three models were built in Abaqus FEA software. The first model A3D in Fig. 1 represents a complex three-dimensional model. The second L2D and the third H2D model shown in Fig. 2 represent simple two-dimensional models. The stiffness of the subgrade beneath the structure in the second and third model was modelled as spring constants calculated based on the equations given in the reference [8] model L2D and [10] model H2D. The middle range value of Young’s modulus for sand and gravel was used to calculate the subgrade stiffness parameters. In all models, a horizontal displacement in the Y direction of value 20 mm and a vertical force of value 18200 kN were applied to the top of the pier support. The horizontal displacement was caused by the thermal longitudinal expansion of the six-span viaduct deck and the braking force. The vertical force was caused by the dead, superimposed, and live loads acting on the viaduct deck. Finally, the values and distributions of displacements and internal forces in the pier support from the complex model were compared with the values in two simple models. The author focuses on the method of modelling of foundation stiffness of the pier support and its impact on the values of displacements and internal forces in the pier support. A similar structure analysed in this paper was design-checked by the author in Ireland [4].

In the latest period hundreds of concrete viaducts were built in Poland within a short time range. The cases of destruction of concrete road viaducts described by the author in the article concern in the construction of such structures in various parts of our country, such as central regions of Poland, Warmia-Masuria, south – east - a total of about 30 objects. The occurring phenomenon is related to the micro cracks of the cement matrix which are not visible on the surface of the elements and become visible only after the cyclic freezing process as a result of the standard F150 frost resistance test, the so-called the standard method according to Annex N to the PN-B-06265: 2018 standard. The destruction took an unprecedented course and aroused much discussion in the scientific community. This article summarizes this discussion and indicates the root cause of the destruction.