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The assessment of dynamic performance of large-scale bridges typically relies on the deployment of wired instrumentation systems requiring direct contact with the tested structures. This can obstruct their operation and create unnecessary risks to the involved personnel and equipment. These problems can be readily avoided by using non-contact instrumentation systems. However, the cost of off-the-shelf commercial products often prevents their wide adoption in engineering practice. To this end, the dynamic performance of the biggest one-pylon cable-stayed bridge in Poland is investigated based on data from a consumer-grade digital camera and open access image-processing algorithms. The quality of these data is benchmarked against data obtained from conventional wired accelerometers and a high-end commercial optical motion capture system. Operational modal analysis is conducted to extract modal damping, which has a potential to serve as an indicator of structural health. The dynamic properties of the bridge are evaluated against the results obtained during a proof loading exercise undertaken prior to the bridge opening. It is shown that a vibration monitoring system based on consumer-grade digital camera can indeed provide an economically viable alternative to monitoring the complex time-evolving dynamic behaviour patterns of large-scale bridges.

As we all know, this year may not have started very well due to the Covid-19 pandemic, but—observing an improvement of the situation in many countries—the hope is rising in our hearts and we firmly...

In this paper, dynamic analyses of two untypical, modern footbridges made of glued-laminated timber are presented. One of them is among the longest cable-stayed bridges for pedestrians in the world, made of such a structural material. Both structures are qualified as having low sensitivity to vibrations. The results of numerical modal analysis using FEM and non-destructive experimental dynamic tests of investigated footbridges are compared. Important differences in obtained results are captured, which are identified as the positive effect in relation to design aspects. Moreover, the same in situ measurements confirm the high level of damping in footbridges made of glued-laminated wood, which is a very significant and distinguishing feature not commonly recognized. The study also calls attention to the choice of timber as an advisable material for footbridges. This is not only because of environmentally friendly and aesthetic reasons, but also due to providing highly satisfying vibration comfort for pedestrians.

The paper describes architectural competition designs of three different pedestrian bridges in Poland. Nowadays footbridges not only have to meet communication requirements but also have to be well adapted to the surrounding environment. Presented footbridge concepts show different approaches to their inclusion in the landscape combined with engineering and architectural vision.

IABSE is one of the most important associations uniting civil engineers from all over the world. Founded in 1929, it has existed for over 90 years. From the very beginning Polish engineers have tak...

Bystrzyckie Lake is a dam lake created in 1917, located in the Owl Mountains near the village of Zagórze Śląskie (Poland), at the foot of the medieval Grodno Castle. The lake along with the castle have very soon become tourist attractions of the region. A steel suspension footbridge was built in 1968 in the upper part of the lake. In 2010 technical condition of the footbridge was so bad that a decision was made to demolish it and to erect a new one in the same place. This paper describes construction and design details of the new footbridge – a stress ribbon structure with two spans of 22.00 + 80.00 m and the total length of 125.60 m. The bridge deck consists of precast segments made of architectural concrete, placed on four bearing cables. A pedestrian path with a usable width of 2.00 m is located on the deck, widening to 4.00 m and 4.50 m in places of viewing platforms. The footbridge in Zagórze Śląskie was opened in summer 2019 and soon has become a landmark and an attraction for tourists visiting the region.

Monitoring systems have given the possibility of varied and long-term observation of bridge structures. The paper prestents the analysis of temperature impact on various bridge elements. The data comes from three different large bridges in Poland, equipped with extensive monitoring systems, namely from an arch bridge in Puławy (built in 2008), cable-stayed bridge in Płock (built in 2005) and the cable-stayed bridge in Wrocław (built in 2011). After few years of observation an enormous and valuable database of measured parameters was stored. The analysis shows how temperature changes between individual bridge components (e.g. between decks, pylon and stay cables) affect the structure mechanical behaviour and whether the influence fulfil the standards’ recommendations. Due to various static schemes and materials used in the described bridges, individual and non-typical impact of thermal loads is expected.

In this paper a system of the Rędziński bridge will be described. The Rędziński bridge is the biggest object along the A8 motorway around the city of Wrocław and the biggest concrete cable-stayed bridge in Poland. For the purposes of the bridge monitoring a system of 222 sensors was installed. Results from the first 5 years of work of the SHM will be presented below.

The development of civil engineering in Poland over 1000 years was discussed. Particular attention was paid to outstanding innovative constructions created after World War II. Innovative buildings, halls, stadiums, masts, high-rises and bridges were presented. It was in Poland where the first welded steel road bridge in Europe and the highest mast in the world were built. Europe's largest extradosed and innovative arched and composite bridges have been built recently.

Examples of solutions for arch bridges recently developed in Poland are presented. The content of the paper was limited to two issues. First: Construction of spans of concrete arched bridges from various types of prefabricated elements. Second: Construction of steel or hybrid arch bridges in which the arches were made of cold bended steel sections. The presented solutions are characterized by low material consumption and low construction costs.

The presented footbridge connects the centre of Poznan with Ostrow Tumski Island and the campus of the Poznan University of Technology.

The road infrastructure in Poland has been intensively developed and modernised over the last years. During the past decade more than 2500 new bridges have been built along the main roads and motorways, including several large multi-span structures with a length of more than 500 m. This paper describes the design and construction of the cable-stayed bridge in Wrocław and the extradosed bridge in Kwidzyn. Both structures are the largest concrete bridges built in Poland and are also among world leaders in their class. They can presently be considered to be the greatest achievements of Polish civil engineering. The Rędziński Bridge over the Odra River in Wrocław is a 612 m long cable-stayed bridge with two spans of 256 m suspended to a single 122 m high concrete pylon. The bridge in Kwidzyn is a 808 m long six-span extradosed bridge with two longest spans of 204 m. The paper concludes with a brief comparison of both structures including consumption of materials and costs.

The Rędziński Bridge in Wrocław is the biggest Polish concrete cable-stayed bridge. It is equipped in a large Structural Health Monitoring system which has been collecting the measured data since the bridge opening – from the year 2011. After 7 years [2] a comparison between the measured data and the FEM calculations is presented in this paper.

Heavy car traffic on main streets is nowadays a major problem of modern cities. In order to improve safety of pedestrians and cyclists and at the same time maintain fluent car traffic flow, a separation of those two traffic types may be desirable in some cases. This paper presents different possible solutions to this problem implemented in Polish cities.Underpasses or footbridges across busy streets in urbanized areas can be an alternative to pedestrian crossings. Footbridges apart from ensuring safe communication, can be attractive architectural elements of urban space. The cable stayed footbridge in Jaworzno will not only facilitate safe pedestrian communication between a large housing estate and a sports hall, but is likely to become a landmark of the city.An attractive proposal for pedestrians and cyclists moving along crowded and polluted streets are routes marked out on riverside areas. The footbridges connecting islands on the Odra River in Wrocław not only have enabled efficient communication, but also have changed the islands into easily accessible places of relaxation. Free communication along the river embankments intersected by busy routes can be facilitated by building additional passages under existing bridges. The subject of the competition in Poznań was a footbridge over the Warta River, located close to the historical part of the city. Its implementation, apart from the main function of connecting the university campus with the city centre, will create a great recreational place for students and all citizens.An unusual supplement for traditional means of transport in urbanized area can be an aerial tramway line. “Polinka” cable car that connects both parts of the campus of Wrocław University of Science and Technology separated by the Odra River have turned out to be an unconventional and attractive alternative to a typical footbridge.

Heavy car traffic on main streets is a major problem of modern cities. In order to improve safety of pedestrians and maintain the car traffic flow, a separation of the two traffic types may be sometimes desirable. It can be achieved either by building underground passageways or footbridges. This paper presents the latter solution – a safe pedestrian route from a housing estate to a sports hall of the city centre of culture and sports in Jaworzno (Poland). The investor ordered a landmark structure that will lead pedestrians safely directly to the vicinity of the hall, crossing a busy street. The design assumes a five-span structure with the main cable-stayed span suspended to a steel column-shaped inclined pylon. The deck is a cost-efficient simple structure consisting of a steel grillage composite with a reinforced concrete deck slab.

This paper describes the largest structure along the motorway ring road of Wroclaw (Poland)—a cable-stayed bridge over the Odra River near Redzin barrage. The river flows there in its main bed, whi...

The Centennial Hall, a reinforced concrete structure with an auditorium for 10000 people, was opened in Wroclaw, Poland (then Breslau, Germany), in 1913 after two years of construction. Its dome, covering the whole building, has a diameter of 65.0 m and in the year it was completed was the largest reinforced concrete dome in the world. This broke the previous record, held by the dome of the Pantheon in Rome (43.3 m), which had lasted for 1787 years. This paper describes the structure of the building, its condition after 100 years of use and the renovation works carried out in 2009–2011. An important part of the renovation was strengthening the lower (tension) ring of the ribbed dome by way of external prestressing. Details concerning the assessment of the technical condition of the hall, numerical calculations and the proposed system of strengthening are presented. In 2006 the monumental Centennial Hall was listed as a UNESCO World Heritage Site for its pioneering reinforced concrete structure, designed in the style of modernism.

The road and railway infrastructure in Poland has been intensively developed and modernized for the last years. Around 300 new bridges are built annually. Among the new structures, there is a group of modern extradosed bridges. This paper presents examples of short-, medium-, and long-span extradosed bridges designed and built in recent years in Poland. The following structures are described in details: (1) the first Polish extradosed bridge; (2) two-span landmark viaduct over motorway; (3) multi-span curved motorway bridge; (4) the longest Polish extradosed bridge; (5) tramway extradosed bridge; and (6) conceptual designs. The paper is concluded with geometrical parameters characterizing presented structures. The parameters are compared with values obtained for cable-stayed bridges and extradosed bridges built worldwide.

The road and railway infrastructure in Poland has been intensively developed and modernized for the last years. Around 300 new bridges are built annually. Among the new structures there is a group of modern extradosed bridges.This paper presents examples of short-, medium- and long-span extradosed bridges designed and built in recent years in Poland. The following structures are described: the first Polish extradosed bridge; two-span landmark viaducts over motorways; multi-span curved motorway bridge; the largest Polish extradosed bridge; conceptual designs.Structural details and construction technology of the above mentioned bridges are described. The paper is concluded with a comparison of basic geometrical characteristics of presented bridges.

The largest bridge along the motorway ring road of Wroclaw is a cable-stayed structure over the Odra River near Redzin water stage of fall. The river flows there in its main bed, while inland navigation uses additional water channels. An island, where the pylon of the new bridge is situated, is located between the river and the channels. The bridge is 1742 m long and consists of a 610 m long southern flyover, a 612 m long cable-stayed main bridge with separate decks suspended to one 122 m high pylon and a 520 m long northern flyover. The superstructure of the main bridge consists of two box girders made of prestressed concrete, one for each carriageway of the highway. The height of the girder is 2.50 m, which is about 1/100th of the main span length. The decks are supported by 80 pairs of stay cables connected to the pylon made of reinforced concrete. The bridge with a deck area of approximately 65 000 m2 was constructed within 36 months.

The paper presents the technical design of an innovative structure of Kazimierz-Ludwinów footbridge in Cracow over the Vistula River. The main span of the footbridge represents very unusual structural form. Static system of its two of three decks can be defined between a fixed beam and a shallow arch. The third deck supported by the two main decks has a sinusoidal profile. The most complex elements of the structure designed with rigorous requirements of architectural forming are indicated. These extraordinary elements are: massive concrete supports with a complicated geometric shape, steel decks of the main span composed of irregular tapered box girders prestressed in the edge parts of the spans and the whole structure of the approach ramps.Some details of numerical modelling of the structure by means of FEM are presented as well as the concept of the footbridge construction technology is discussed.

The majority of viaducts constructed in urban areas are concrete beam viaducts with spans of 25.0÷60.0 m. Due to the specific location of these viaducts, their elevations as well as the structural solutions applied in them are visibly accessible to the users of the transport infrastructure. When shaping such viaducts, it is thus essential to pursue their positive aesthetic reception, meeting the reasonable cost requirement. The material presented in this paper may inspire a debate binding the above-mentioned issues. Conditions for standard bridge architecture have been presented. The paper provides also examples of pier and span shaping in urban concrete viaducts (mainly prestressed concrete viaducts designed by the authors) as well as commentaries on particular solutions. Final conclusion have been drawn.

Not so long ago, a pretty bridge was completed in Poland, over the Vistula River, near the city of Plock. The bridge is made of steel. It is a cable-stayed bridge with a main span of 375 m. The bridge is subjected to permanent structural control by what we will call a ‘monitoring system’.This system monitors the following factors: force in the stays, inclination of the pylons, strains in the structure, wind load. The following gauges were employed: load cells, inclinometers, strain gauges, anemometers. The conclusions were divided into four groups: remarks concerning the operation of the system, remarks on the safety of the bridge, knowledge-building observations on the behavior of cable-stayed structures and data on real environmental effects on bridges. The conclusions drawn after the first two years of data acquisition are reassuring. The behavior of the bridge is not unexpected and the parameters measured are within the foreseen limits.

Designing of curved cable-stayed bridges allows to increase safety of its users (drivers). They also allow to adjust bridge to the existing or planned road communication configuration. Some unexpected behaviour of such structures may appear during its exploitation. Therefore it is necessary to gather information of ways of designing and non-typical behaviour of such bridges.Two curved cable-stayed bridges located in Poland are presented in the paper, including description of the structures, the way of their construction and their behaviour during exploitation and filed tests. The first one is a cable-stayed bridge in Skorogoszcz (Poland), which has two spans of 59.75 m each. Pylon is made of steel and the deck has composite structure: three beams are made of steel and plate is made of concrete. The second bridge is a viaduct along National Road No. 94 over the A4 highway in Wykroty. It is a continuous double span (45.47 + 45.28 m) cable-stayed structure with a prestressed concrete deck and the V-shaped pylons are made of steel.

The presented footbridge, with a main span length of 90 m, is one of the longest cable-stayed bridge structures made of glued-laminated wood. The footbridge joints two countries, Poland and Slovakia, and has been erected in a very attractive tourist area. Inhabitants waited for a footbridge almost 100 years, from 1914 to 2006. On 12 August 2006 about 1000 people (inhabitants and tourists) took part in the Opening Ceremony. On the last Sunday of summer holidays 2006 about 11000 pedestrians crossed the border during one day, as notified by the frontier police. It shows, how this footbridge is important in this region. The design and erection processes as well as experimental investigations concerning dynamical behaviour of this footbridge are described in this paper.

Highway ring road of Wrocław is a very important part of an urban communication network which is now under modernization work. It will connect the existing A4 highway with the S8 expressway being under construction. The ring road is 26.765 km long. Forty bridge structures were designed along or over it. Total length of highway bridges and viaducts is more than 6 km, that is equivalent to 22% of the whole route. The longest bridge is a concrete cable-stayed structure over the Odra River. The river flows in its main bed, while inland navigation uses additional channel with two locks. There is an island located between the river and the channel. The planned bridge is 1742 m long and consists of: south flyover 610 m long with continuous eleven span prestressed concrete box structure; main bridge 612 m long with two separate decks connected to a single concrete H-shaped pylon; north flyover 520 m long with continuous girders made of prestressed concrete.

The road and railway infrastructure in Poland has been intensively developed and modernized for the last years. Around 300 new bridges are built annually. Among the new structures there is a group of modern long span bridges. This paper presents examples of selected, most interesting large road bridges built in recent years in Poland. The following structures are described: two largest extradosed bridges in Europe – with spans exceeding 200 m; the largest arch bridge in Poland with 270 m long fixed arches and an expressway bridge with 200 m long arch span; two cable-stayed bridges. Structural configuration and construction technology of the above mentioned bridges are described.