No abstract

The article investigates the causes of the Morandi viaduct collapse in Genoa. This three-span viaduct was a part of the A10 motorway leading to Savona. The structure design of the viaduct supports and diagonal stay cables was unique. The viaduct included three cable-stayed system, each supported a three-span continuous beam by two sets of prestressed concrete cables on the two sides of the pylon across the width. The pair of V shapes piers supported upside-down V pylons that supported the top ends of two pairs of diagonal stay cables. The stays were constructed from steel cables with prestressed concrete shells poured on. This article provides information on the technical condition of the viaduct and the way of strengthening the cables in the early 1990s. At that time, the author of the article visited the structure. In August 2018, the viaduct collapse occurred, and one of the structure supports collapsed. In June 2019, during the demolition process, the other two supports were destroyed. Since in Venezuela and Libya there are still two more bridges with a structure similar to that in Italy, the concept of strengthening the structure, as proposed by the author of the article 25 years ago, may still be useful.

Trwają prace nad stworzeniem nowej struktury przepisów techniczno-budowlanych w mostownictwie. Wymagania zawarte w obowiązującym rozporządzeniu dotyczącym drogowych obiektów inżynierskich są obecnie przenoszone do nowej struktury składającej się z dwóch poziomów: rozporządzenia ministra właściwego ds. transportu i kilku wytycznych technicznych rekomendowanych przez tegoż ministra. Przy czym stosowanie wytycznych będzie dobrowolne, na podobieństwo stosowania polskich norm. W niniejszym artykule Koordynatorzy pracy omawiają dawną i nową strukturę przepisów techniczno-budowlanych oraz podają wymagania, które obecnie znajdują się we wstępnej wersji projektu nowego rozporządzenia. Wymagania te stanowią zbiór tzw. wymagań podstawowych, które należy zapewnić przy projektowaniu, budowie i utrzymaniu obiektów inżynierskich w przewidywanym okresie użytkowania.

Short-term operational safety of original European road bridges Looking at the basic requirements for building structures in Regulation (EU) No 305/2011 of the European Parliament and of the Council, Professor Janusz Rymsza explores the operational safety of structures. He elaborates the need to ensure durability, or the adequate safety of the structure over its assumed service life, and looks at the possibility of demolishing structures and the inadequate operational safety of building structures due to their lack of durability. This article analyses the cost and effectiveness of the safety of bridges, and the requirements for building structures, diving into what has changed in bridge construction over the past 30 years.

The paper describes the impact of the individual components of animal passages on the efficiency of their use. Research was conducted with regard to four species of ungulates: elk, deer, roe deer and boar. The analyzed equipment are road lighting, shielding vegetation, rootwood and tree stumps, anti-glare shields, rocks, fencing. The analysis were made on the basis of surveys which were filled by 87 road operators. Own method of surveys answers analysis was developed and it consists of two stages. It was established that road lighting located in the vicinity of a passage negatively affected its use by the analyzed species. Anti-glare shields clearly positively influence on the efficiency of ecology road infrastructure. Shielding vegetation, rootwood and tree stumps, and anti-glare shields positively influenced on the use of animal passages. Other components do not influence on efficiency of animal passages.