W 2011 r. zakończono remont i renowację zabytkowego mostu z 1909 r. w Lublinie. Przebieg prac zos... more W 2011 r. zakończono remont i renowację zabytkowego mostu z 1909 r. w Lublinie. Przebieg prac został zrelacjonowany w szczegółach w artykule [1]. Most został wykonany w technologii F. Hennebique'a, jako żelbetowy ramowy. Ustrój nośny ma układ ciągły, połączony sztywnymi węzłami z filarami w postaci rzędów słupów żelbetowych, wyprowadzonych z pali żelbetowych, nawet dziś nazywanych palami Hennebique'a 1. Pomost w postaci żelbetowej płyty ortotropowej o wydzielonych belkach głównych oraz przyskrajnych pomocniczych. W płaszczyźnie pomostu w kierunku poprzecznym zastosowano poprzecznice. Most w całości ma długość 42 m, przy czym rozpiętości mierzone w osiach filarów mają długości 5 × 8,0 m. Filary są stężone poprzez poziomy rygiel na wysokości przejścia pali w słupy. W skrajnych polach każdego filara zastosowano stężenie krzyżulcowe. Przekroje poprzeczne pali i słupów mają kształt kwadratu o boku 40 cm. W przekroju poprzecznym konstrukcja i organizacja ruchu na moście jest symetryczna względem osi. W szerokości skrajni wydzielono dwa chodniki o jednakowej szerokości 2,45 m, jezdnia ma szerokość 11,0 m. Całkowita szerokość skrajni wynosi 15,90 m. Nośność określona w dokumentach archiwalnych wynosiła 1680 kNm. Z dokonanych przeliczeń wynika, że w odniesieniu do obowiązującej obecnie normy PN-EN-1991-2 [2] most odpowiada nośności równoważnej kładce dla pieszych obciążanej wg LM4.
Human Cytomegalovirus (HCMV or HHV-5) is a life-threatening pathogen in immune-compromised indivi... more Human Cytomegalovirus (HCMV or HHV-5) is a life-threatening pathogen in immune-compromised individuals. Upon congenital or neonatal infection, the virus can infect and replicate in the developing brain, which may induce severe neurological damage, including deafness and mental retardation. Despite the potential severity of the symptoms, the therapeutic options are limited by the unavailability of a vaccine and the absence of a specific antiviral therapy. Furthermore, a precise description of the molecular events occurring during infection of the central nervous system (CNS) is still lacking since observations mostly derive from the autopsy of infected children. Several animal models, such as rhesus macaque CMV, have been developed and provided important insights into CMV pathogenesis in the CNS. However, despite its evolutionary proximity with humans, this model was limited by the intracranial inoculation procedure used to infect the animals and consistently induce CNS infection. Furthermore, ethical considerations have promoted the development of alternative models, among which neonatal infection of newborn mice with mouse cytomegalovirus (MCMV) has recently led to significant advances. For instance, it was reported that intraperitoneal injection of MCMV to Balb/c neonates leads to infection of neurons and glial cells in specific areas of the brain. These findings suggested that experimental inoculation of mice might recapitulate the deficits induced by HCMV infection in children. Nevertheless, a dynamic analysis of MCMV infection of neonates is difficult to perform because classical methodology requires the sacrifice of a significant number of animals at different time points to analyze the viral burden and/or immune-related parameters. To circumvent this bottleneck and to enable future investigations of rare mutant animals, we applied in vivo imaging technology to perform a time-course analysis of the viral dissemination in the brain upon peripheral injection of a recombinant MCMV expressing luciferase to C57Bl/6 neonates.
Streszczenie: W artykule jest rozpatrywany problem graffiti na mostach. Graffiti można postrzegać... more Streszczenie: W artykule jest rozpatrywany problem graffiti na mostach. Graffiti można postrzegać, jako formę artystycznej wypowiedzi. Przytoczono dwa historyczne przykłady, jeden z czasów antyku i drugi z bliskiej historii z lat czterdziestych. Podjęto próbę zdefiniowa-nia graffiti na podstawie rozpoznania środowiska lubelskich kręgów graffiti. Powstała opisowa charakterystyka graffiti wskazuje na stałe, niezależne a nawet nielegalne działanie, które nie jest możliwe do ograniczenia. Rozpatrzono graffiti na przykładzie mostów Santiago Calatravy oraz prostego statystycznego ujęcia ocen estetycznych graffiti dokonanych przez studentów WBiA PL. We wnioskach poddano pod rozwagę opcje pozostawianie niektórych obrazów graffiti na mostach, kierując się racjonalnym osądem ich wyrazu artystycznego.
The aim of the paper is to characterize the inconsistencies appearing during the bridge design pr... more The aim of the paper is to characterize the inconsistencies appearing during the bridge design process, maintenance and ecological issues which were caused by lack of proper environmental management system. Several examples of the road and bridge investments carried out in Poland in the last decade have provided the basis to formulate several statements and questions. The difference between the approach of bridge engineers and environmental experts to the concept of animal migrations is shown against the background of technical and environmental standards that were implemented in the investment. The existing problems are of dual nature, the first group being very general issues i.e. concerning the concept of ecology, while the other one involves detailed matters, e.g. the appearance of a bridge. Several questions of great significance have been formulated and addressed to ecologists. The answers are indispensable for bridge engineers to work on technical aspects of proper design of ...
GDDKiA O.Lublin sekretariat@lublin. gddkia.gov.pl W związku z prowadzonymi robotami wystąpiła kon... more GDDKiA O.Lublin sekretariat@lublin. gddkia.gov.pl W związku z prowadzonymi robotami wystąpiła konieczność wymiany biegnącego w nasypie drogowym przepustu na nowy i wówczas nastąpiło częściowe odsłonięcie mostu (fot. 2). Most i przepust są usytuowane nad ciekiem bez nazwy. Pracownicy Katedry Dróg i Mostów Politechniki Lubelskiej (KDiM PL), Maciej Kowal i Sławomir Karaś, wykonali inwentaryzację odsłoniętych fragmentów. Pobrano próbki betonu i cegły
The article looks into the problem of graffiti on bridges. Graffiti can be seen as a form of arti... more The article looks into the problem of graffiti on bridges. Graffiti can be seen as a form of artistic expression. There are quoted two historical examples of graffiti, one of the times of antiquity and the other from a more recent historical period, i.e. 1840s. There has been an attempt to define graffiti on the basis of a survey conducted among the Lublin graffiti circles. The resulting descriptive definition of graffiti indicates a stable, independent or even illegal action which seems to be impossible to be curbed. The graffiti was examined on some examples of Santiago Calatrava’s bridges. By means of a simple statistical method applied to the results of a survey conducted among student groups and by means of 1/0 estimation (positive-1/negative-0 impression) of graffiti on bridges, some reliable results have been obtained. It was concluded that, optionally, some of bridge graffiti can be accepted and therefore can be kept as an enhancement of urban surroundings.
The existing structures located on the railway line Grodzisk Mazowiecki - Zawiercie are analysed ... more The existing structures located on the railway line Grodzisk Mazowiecki - Zawiercie are analysed from the point of view of the required adjustments to accommodate high-speed rail (HSR) in the paper. The total number of sixty eight (68) culverts and thirty one (31) bridges were evaluated for their suitability, upon the required adjustment, to 250-350 km/h line speed by way of numerical analyses and experimental tests including load tests and condition surveys. The authors give recommendations for altering the static system from simply supported for fully integral construction. Moreover, an overview of publications on high-speed rail is presented.
Under this project two Mycenaean bridges, both located near the village of Arkadiko in Peloponnes... more Under this project two Mycenaean bridges, both located near the village of Arkadiko in Peloponnese (Greece), were examined through a field survey. These bridges, believed to be one of the oldest preserved bridges in the world, are part of the cultural heritage of humanity. This paper presents the results of a basic static analysis with identification of the weak points of the structure, which are the consequence of its transformation from the original corbelling system to a mixed corbelling and arch system. It seems to be accidental but indispensable according to principles of engineering mechanics.
The great usefulness of uniaxial visco-elastic models, especially in highway engineering pavement... more The great usefulness of uniaxial visco-elastic models, especially in highway engineering pavement theory, composites and other civil engineering disciplines were the reason for undertaking the trial to find a complete solution for the generalization of Kelvin-Voigt body. Here the elements of higher rank than velocities of strain and stress are considered. Carson’s transformation simultaneously with residuum theorem are used for solutions derivation. The introduced procedure can be also used for more complicated differential or integral forms of constitutive equations, as well as for non homogenous initial conditions. The Burgers’ body is examined. Finally, as an example the vibration of simple beam is shown.
Regulations on which designers base their process of designing of any engineer structures should ... more Regulations on which designers base their process of designing of any engineer structures should include and combine mechanics, loads and dimensioning. It is not always the case as far as eurocodes are concerned. Ambiguities appear everywhere, which sometimes leads to incorrect understanding of a norm. The authors meticulously analysed basic mechanical terms. Their digressions began with the concepts of strain and deformation that have discrepant definitions in sources from other countries. The next part of article discusses the concept of „shear lag”. It is treated as an elementary concept in the eurocodes, although is has not been defined yet. Other sources define it as cooperating width and shear strain in the beam flanges or as stretching. Polish translation mentions the effect of „wide stripes”. The authors focused also on dynamics – especially while discussing first natural frequencies denoted as “n0”. They scrutinised the norm EN 1991-2 in which dynamic problems of brid...
The paper presents the results investigation of old concrete. The material was retrieved from M.... more The paper presents the results investigation of old concrete. The material was retrieved from M. Lutoslawski Bridge which is located in Zamojska Street. M. Lutoslawski built two bridges in Lublin by using Francois Hennebique projects. The carried out investigations include recognition in situ and during laboratory tests. Among others, the concrete compression strength and the diagnosis of concrete microstructure were made by means of SEM and EDS techniques. The conclusions pertain to both macro and microscopic analyses. The concrete strength results were compared with other authors' results obtained for similar old concretes.
The article was taken a technical problem of human-technical heritage. The thing applies to the 1... more The article was taken a technical problem of human-technical heritage. The thing applies to the 1st M. Lutoslawski’s bridge in Lublin. Years of neglect caused by a deficiency of knowledge about the bridge worth, its uniqueness meant that the structure is close to the limit condition in the sense of technical standards. This does not mean that at any moment the bridge will collapse, but each subsequent year of its duration is a further development of corrosion and cost increases of future repair. In terms of sustainable development - should endeavor not to impoverish future generations of unique monument.
Mosty ze względu na ich trwałość w krajobrazie stają się punktami odniesienia w różnych aspektach... more Mosty ze względu na ich trwałość w krajobrazie stają się punktami odniesienia w różnych aspektach, w tym w szczególności społecznym, architektonicznym i estetycznym. Można mnożyć przykłady opisanych sytuacji, są to np. Tower Bridge, Puente del Alamillo, Pont Saint-Bénézet (d’Avignon), Karlův most czy Ponte Sant’Angelo. Jednakże celem analiz w niniejszym artykule są mosty zajmujące skrajnie marginalną pozycję do wymienionych sławnych mostów. Są to małe mosty przez rzeki Konotopa i Piwonia w miejscowości Parczew na Lubelszczyźnie. Lokalna społeczność dostrzegła konieczność zmiany z szarej monotonii na formy bardziej atrakcyjne o indywidualnych cechach. Jeśli istniejące mosty będą zadbane, zaaranżowane, przez podkreślenie istotnych linii silną lub delikatną barwą, nawiązanie do otoczenia przez zharmonizowanie lub przez utworzenie lokalnej dominanty. Wiele już zrobiono, kilka zaniedbanych obiektów oczyszczono, odnowiono, zmodernizowano balustrady i pomosty, uporządkowano stożki skarp, z...
The article dealt with a problem of graffiti on bridges. Graffiti can be perceived as a form of a... more The article dealt with a problem of graffiti on bridges. Graffiti can be perceived as a form of artistic expression. Two historical examples of graffiti, one from antiquity times and the other one from the forties of the past century were presented. An attempt was made in order to define the graffiti on the basis of the analysis of the Lublin’s graffiti culture The obtained descriptive characteristic/definition of graffiti indicates stable, independent and even illegal activity which seems to be impossible to be constricted. The graffiti was examined on the example of Santiago Calatrava bridges. On the basis of simple statistical method, which was applied, the groups of students assessed the displayed graffiti on bridges by answering the questions by means of 1/0 estimation (positive/negative impression). The reliable results were obtained. It was concluded that some graffiti on bridges can optionally be accepted and therefore can be remained as a result of rational judgement of the...
The article describes service parameters and effectiveness of the environmental elements of anima... more The article describes service parameters and effectiveness of the environmental elements of animal crossings on the S17 expressway. Animal transitions on the section of S17 expressway between junctions „Kurów West” and „Lublin Felin” were described. The requirements of environmental protection at the design stage and during the construction works were shown. Article gives an accunt of the works performed in order to protect the natural environment in areas adjacent to the route, and solutions provided to design objects and the basic functions of animal transitions. Paper summarizes the relevance of the applied solutions and their locations in the field.
This paper discusses the problem of reviving the Bystrzyca River in Lublin in the vicinity of the... more This paper discusses the problem of reviving the Bystrzyca River in Lublin in the vicinity of the historic M. Lutosławski Bridge in the disctrict of Kalinowszczyzna. Historically, this area was an outer part of the city. The north-estern tract turnpike was located there. Until the twentieth century, there was a wooden bridge which was replaced by a reinforced concrete (RC) one. Currently, the space around the bridge is undeveloped. Moreover, there are no parks, recreational areas or cultural venues there. The bridge itself is a technical monument of great value. Despite general awareness of the importance of the bridge, not enough is done to protect it for posterity. The current technical assessment of the bridge indicates its grave condition resulting from rapidly developing corrosion of the carrying RC elements. The paper describes the surroundings of the bridge and contains some suggestions regarding the use of the bridge as a park avenue and as a stage for music concerts.
The paper examines the application of the tensor calculus to the classic problem of the pure tors... more The paper examines the application of the tensor calculus to the classic problem of the pure torsion of prismatic rods. The introduction contains a short description of the reference frames, base vectors, contravariant and covariant vector coordinates when applying the Einstein summation convention. Torsion formulas were derived according to Coulomb’s and Saint-Venant’s theories, while, as a link between the theories, so-called Navier’s error was discussed. Groups of the elasticity theory equations were used.
Arch bridges have always boasted a strong aesthetic value. However, their design is challenging d... more Arch bridges have always boasted a strong aesthetic value. However, their design is challenging due to dynamic excitations. It regards, above all, an area up to ¼ of a bridge length. In bridge dynamics numerical analyses, the basic importance is attached to the natural vibration frequency corresponding to the first bending mode. The multiple first mode is connected to the horizontal shift of a platform or arches, additionally coupled with the deformation corresponding to torsion. In the bridge standards, the first bending mode was adopted as default followed subsequently by higher rank modes of torsional or transversal shapes which do not always occur. This paper describes fourteen numerical models of various arches used in bridge design. The arch bridge, of vertical arches, constitutes a reference. Other models are their varieties through a change of the arch height, a method of connecting platforms and arches at a head and their resulting interaction. Furthermore, variability of arch tilts from a vertical plane was discussed. Conclusions are not unanimously final from the technical point of view; nevertheless, certain beneficial solutions, corresponding to the models of structures of higher natural frequencies, can be indicated.
In Poland, the ecological corridor map overlaps with forests, as well as with the road network. T... more In Poland, the ecological corridor map overlaps with forests, as well as with the road network. The police have recorded near a 100% increase in animal mortality over the last decade. In most cases, bridges automatically serve as passages for animals, even if they have not been considered and designed for such a role. The following facts are importand: silence is positive for animals, natural guides are better then fences and walls, gentle lighting moderates car lights at night. Therefore, the semi-transparent canopy-type noise screens should be used, as well as olfactory tracks. The solution proposed here is beneficial for both the environment and road users. For the proper functioning of the bridge, it is crucial to take into consideration that animals are more efficiently guided by their smell than by channelling fences. However, the commonly used fences would also be provided. Olfactory traces can come in two kinds: animal faecal matter and mating scents. In a natural habitat, ...
W 2011 r. zakończono remont i renowację zabytkowego mostu z 1909 r. w Lublinie. Przebieg prac zos... more W 2011 r. zakończono remont i renowację zabytkowego mostu z 1909 r. w Lublinie. Przebieg prac został zrelacjonowany w szczegółach w artykule [1]. Most został wykonany w technologii F. Hennebique'a, jako żelbetowy ramowy. Ustrój nośny ma układ ciągły, połączony sztywnymi węzłami z filarami w postaci rzędów słupów żelbetowych, wyprowadzonych z pali żelbetowych, nawet dziś nazywanych palami Hennebique'a 1. Pomost w postaci żelbetowej płyty ortotropowej o wydzielonych belkach głównych oraz przyskrajnych pomocniczych. W płaszczyźnie pomostu w kierunku poprzecznym zastosowano poprzecznice. Most w całości ma długość 42 m, przy czym rozpiętości mierzone w osiach filarów mają długości 5 × 8,0 m. Filary są stężone poprzez poziomy rygiel na wysokości przejścia pali w słupy. W skrajnych polach każdego filara zastosowano stężenie krzyżulcowe. Przekroje poprzeczne pali i słupów mają kształt kwadratu o boku 40 cm. W przekroju poprzecznym konstrukcja i organizacja ruchu na moście jest symetryczna względem osi. W szerokości skrajni wydzielono dwa chodniki o jednakowej szerokości 2,45 m, jezdnia ma szerokość 11,0 m. Całkowita szerokość skrajni wynosi 15,90 m. Nośność określona w dokumentach archiwalnych wynosiła 1680 kNm. Z dokonanych przeliczeń wynika, że w odniesieniu do obowiązującej obecnie normy PN-EN-1991-2 [2] most odpowiada nośności równoważnej kładce dla pieszych obciążanej wg LM4.
Human Cytomegalovirus (HCMV or HHV-5) is a life-threatening pathogen in immune-compromised indivi... more Human Cytomegalovirus (HCMV or HHV-5) is a life-threatening pathogen in immune-compromised individuals. Upon congenital or neonatal infection, the virus can infect and replicate in the developing brain, which may induce severe neurological damage, including deafness and mental retardation. Despite the potential severity of the symptoms, the therapeutic options are limited by the unavailability of a vaccine and the absence of a specific antiviral therapy. Furthermore, a precise description of the molecular events occurring during infection of the central nervous system (CNS) is still lacking since observations mostly derive from the autopsy of infected children. Several animal models, such as rhesus macaque CMV, have been developed and provided important insights into CMV pathogenesis in the CNS. However, despite its evolutionary proximity with humans, this model was limited by the intracranial inoculation procedure used to infect the animals and consistently induce CNS infection. Furthermore, ethical considerations have promoted the development of alternative models, among which neonatal infection of newborn mice with mouse cytomegalovirus (MCMV) has recently led to significant advances. For instance, it was reported that intraperitoneal injection of MCMV to Balb/c neonates leads to infection of neurons and glial cells in specific areas of the brain. These findings suggested that experimental inoculation of mice might recapitulate the deficits induced by HCMV infection in children. Nevertheless, a dynamic analysis of MCMV infection of neonates is difficult to perform because classical methodology requires the sacrifice of a significant number of animals at different time points to analyze the viral burden and/or immune-related parameters. To circumvent this bottleneck and to enable future investigations of rare mutant animals, we applied in vivo imaging technology to perform a time-course analysis of the viral dissemination in the brain upon peripheral injection of a recombinant MCMV expressing luciferase to C57Bl/6 neonates.
Streszczenie: W artykule jest rozpatrywany problem graffiti na mostach. Graffiti można postrzegać... more Streszczenie: W artykule jest rozpatrywany problem graffiti na mostach. Graffiti można postrzegać, jako formę artystycznej wypowiedzi. Przytoczono dwa historyczne przykłady, jeden z czasów antyku i drugi z bliskiej historii z lat czterdziestych. Podjęto próbę zdefiniowa-nia graffiti na podstawie rozpoznania środowiska lubelskich kręgów graffiti. Powstała opisowa charakterystyka graffiti wskazuje na stałe, niezależne a nawet nielegalne działanie, które nie jest możliwe do ograniczenia. Rozpatrzono graffiti na przykładzie mostów Santiago Calatravy oraz prostego statystycznego ujęcia ocen estetycznych graffiti dokonanych przez studentów WBiA PL. We wnioskach poddano pod rozwagę opcje pozostawianie niektórych obrazów graffiti na mostach, kierując się racjonalnym osądem ich wyrazu artystycznego.
The aim of the paper is to characterize the inconsistencies appearing during the bridge design pr... more The aim of the paper is to characterize the inconsistencies appearing during the bridge design process, maintenance and ecological issues which were caused by lack of proper environmental management system. Several examples of the road and bridge investments carried out in Poland in the last decade have provided the basis to formulate several statements and questions. The difference between the approach of bridge engineers and environmental experts to the concept of animal migrations is shown against the background of technical and environmental standards that were implemented in the investment. The existing problems are of dual nature, the first group being very general issues i.e. concerning the concept of ecology, while the other one involves detailed matters, e.g. the appearance of a bridge. Several questions of great significance have been formulated and addressed to ecologists. The answers are indispensable for bridge engineers to work on technical aspects of proper design of ...
GDDKiA O.Lublin sekretariat@lublin. gddkia.gov.pl W związku z prowadzonymi robotami wystąpiła kon... more GDDKiA O.Lublin sekretariat@lublin. gddkia.gov.pl W związku z prowadzonymi robotami wystąpiła konieczność wymiany biegnącego w nasypie drogowym przepustu na nowy i wówczas nastąpiło częściowe odsłonięcie mostu (fot. 2). Most i przepust są usytuowane nad ciekiem bez nazwy. Pracownicy Katedry Dróg i Mostów Politechniki Lubelskiej (KDiM PL), Maciej Kowal i Sławomir Karaś, wykonali inwentaryzację odsłoniętych fragmentów. Pobrano próbki betonu i cegły
The article looks into the problem of graffiti on bridges. Graffiti can be seen as a form of arti... more The article looks into the problem of graffiti on bridges. Graffiti can be seen as a form of artistic expression. There are quoted two historical examples of graffiti, one of the times of antiquity and the other from a more recent historical period, i.e. 1840s. There has been an attempt to define graffiti on the basis of a survey conducted among the Lublin graffiti circles. The resulting descriptive definition of graffiti indicates a stable, independent or even illegal action which seems to be impossible to be curbed. The graffiti was examined on some examples of Santiago Calatrava’s bridges. By means of a simple statistical method applied to the results of a survey conducted among student groups and by means of 1/0 estimation (positive-1/negative-0 impression) of graffiti on bridges, some reliable results have been obtained. It was concluded that, optionally, some of bridge graffiti can be accepted and therefore can be kept as an enhancement of urban surroundings.
The existing structures located on the railway line Grodzisk Mazowiecki - Zawiercie are analysed ... more The existing structures located on the railway line Grodzisk Mazowiecki - Zawiercie are analysed from the point of view of the required adjustments to accommodate high-speed rail (HSR) in the paper. The total number of sixty eight (68) culverts and thirty one (31) bridges were evaluated for their suitability, upon the required adjustment, to 250-350 km/h line speed by way of numerical analyses and experimental tests including load tests and condition surveys. The authors give recommendations for altering the static system from simply supported for fully integral construction. Moreover, an overview of publications on high-speed rail is presented.
Under this project two Mycenaean bridges, both located near the village of Arkadiko in Peloponnes... more Under this project two Mycenaean bridges, both located near the village of Arkadiko in Peloponnese (Greece), were examined through a field survey. These bridges, believed to be one of the oldest preserved bridges in the world, are part of the cultural heritage of humanity. This paper presents the results of a basic static analysis with identification of the weak points of the structure, which are the consequence of its transformation from the original corbelling system to a mixed corbelling and arch system. It seems to be accidental but indispensable according to principles of engineering mechanics.
The great usefulness of uniaxial visco-elastic models, especially in highway engineering pavement... more The great usefulness of uniaxial visco-elastic models, especially in highway engineering pavement theory, composites and other civil engineering disciplines were the reason for undertaking the trial to find a complete solution for the generalization of Kelvin-Voigt body. Here the elements of higher rank than velocities of strain and stress are considered. Carson’s transformation simultaneously with residuum theorem are used for solutions derivation. The introduced procedure can be also used for more complicated differential or integral forms of constitutive equations, as well as for non homogenous initial conditions. The Burgers’ body is examined. Finally, as an example the vibration of simple beam is shown.
Regulations on which designers base their process of designing of any engineer structures should ... more Regulations on which designers base their process of designing of any engineer structures should include and combine mechanics, loads and dimensioning. It is not always the case as far as eurocodes are concerned. Ambiguities appear everywhere, which sometimes leads to incorrect understanding of a norm. The authors meticulously analysed basic mechanical terms. Their digressions began with the concepts of strain and deformation that have discrepant definitions in sources from other countries. The next part of article discusses the concept of „shear lag”. It is treated as an elementary concept in the eurocodes, although is has not been defined yet. Other sources define it as cooperating width and shear strain in the beam flanges or as stretching. Polish translation mentions the effect of „wide stripes”. The authors focused also on dynamics – especially while discussing first natural frequencies denoted as “n0”. They scrutinised the norm EN 1991-2 in which dynamic problems of brid...
The paper presents the results investigation of old concrete. The material was retrieved from M.... more The paper presents the results investigation of old concrete. The material was retrieved from M. Lutoslawski Bridge which is located in Zamojska Street. M. Lutoslawski built two bridges in Lublin by using Francois Hennebique projects. The carried out investigations include recognition in situ and during laboratory tests. Among others, the concrete compression strength and the diagnosis of concrete microstructure were made by means of SEM and EDS techniques. The conclusions pertain to both macro and microscopic analyses. The concrete strength results were compared with other authors' results obtained for similar old concretes.
The article was taken a technical problem of human-technical heritage. The thing applies to the 1... more The article was taken a technical problem of human-technical heritage. The thing applies to the 1st M. Lutoslawski’s bridge in Lublin. Years of neglect caused by a deficiency of knowledge about the bridge worth, its uniqueness meant that the structure is close to the limit condition in the sense of technical standards. This does not mean that at any moment the bridge will collapse, but each subsequent year of its duration is a further development of corrosion and cost increases of future repair. In terms of sustainable development - should endeavor not to impoverish future generations of unique monument.
Mosty ze względu na ich trwałość w krajobrazie stają się punktami odniesienia w różnych aspektach... more Mosty ze względu na ich trwałość w krajobrazie stają się punktami odniesienia w różnych aspektach, w tym w szczególności społecznym, architektonicznym i estetycznym. Można mnożyć przykłady opisanych sytuacji, są to np. Tower Bridge, Puente del Alamillo, Pont Saint-Bénézet (d’Avignon), Karlův most czy Ponte Sant’Angelo. Jednakże celem analiz w niniejszym artykule są mosty zajmujące skrajnie marginalną pozycję do wymienionych sławnych mostów. Są to małe mosty przez rzeki Konotopa i Piwonia w miejscowości Parczew na Lubelszczyźnie. Lokalna społeczność dostrzegła konieczność zmiany z szarej monotonii na formy bardziej atrakcyjne o indywidualnych cechach. Jeśli istniejące mosty będą zadbane, zaaranżowane, przez podkreślenie istotnych linii silną lub delikatną barwą, nawiązanie do otoczenia przez zharmonizowanie lub przez utworzenie lokalnej dominanty. Wiele już zrobiono, kilka zaniedbanych obiektów oczyszczono, odnowiono, zmodernizowano balustrady i pomosty, uporządkowano stożki skarp, z...
The article dealt with a problem of graffiti on bridges. Graffiti can be perceived as a form of a... more The article dealt with a problem of graffiti on bridges. Graffiti can be perceived as a form of artistic expression. Two historical examples of graffiti, one from antiquity times and the other one from the forties of the past century were presented. An attempt was made in order to define the graffiti on the basis of the analysis of the Lublin’s graffiti culture The obtained descriptive characteristic/definition of graffiti indicates stable, independent and even illegal activity which seems to be impossible to be constricted. The graffiti was examined on the example of Santiago Calatrava bridges. On the basis of simple statistical method, which was applied, the groups of students assessed the displayed graffiti on bridges by answering the questions by means of 1/0 estimation (positive/negative impression). The reliable results were obtained. It was concluded that some graffiti on bridges can optionally be accepted and therefore can be remained as a result of rational judgement of the...
The article describes service parameters and effectiveness of the environmental elements of anima... more The article describes service parameters and effectiveness of the environmental elements of animal crossings on the S17 expressway. Animal transitions on the section of S17 expressway between junctions „Kurów West” and „Lublin Felin” were described. The requirements of environmental protection at the design stage and during the construction works were shown. Article gives an accunt of the works performed in order to protect the natural environment in areas adjacent to the route, and solutions provided to design objects and the basic functions of animal transitions. Paper summarizes the relevance of the applied solutions and their locations in the field.
This paper discusses the problem of reviving the Bystrzyca River in Lublin in the vicinity of the... more This paper discusses the problem of reviving the Bystrzyca River in Lublin in the vicinity of the historic M. Lutosławski Bridge in the disctrict of Kalinowszczyzna. Historically, this area was an outer part of the city. The north-estern tract turnpike was located there. Until the twentieth century, there was a wooden bridge which was replaced by a reinforced concrete (RC) one. Currently, the space around the bridge is undeveloped. Moreover, there are no parks, recreational areas or cultural venues there. The bridge itself is a technical monument of great value. Despite general awareness of the importance of the bridge, not enough is done to protect it for posterity. The current technical assessment of the bridge indicates its grave condition resulting from rapidly developing corrosion of the carrying RC elements. The paper describes the surroundings of the bridge and contains some suggestions regarding the use of the bridge as a park avenue and as a stage for music concerts.
The paper examines the application of the tensor calculus to the classic problem of the pure tors... more The paper examines the application of the tensor calculus to the classic problem of the pure torsion of prismatic rods. The introduction contains a short description of the reference frames, base vectors, contravariant and covariant vector coordinates when applying the Einstein summation convention. Torsion formulas were derived according to Coulomb’s and Saint-Venant’s theories, while, as a link between the theories, so-called Navier’s error was discussed. Groups of the elasticity theory equations were used.
Arch bridges have always boasted a strong aesthetic value. However, their design is challenging d... more Arch bridges have always boasted a strong aesthetic value. However, their design is challenging due to dynamic excitations. It regards, above all, an area up to ¼ of a bridge length. In bridge dynamics numerical analyses, the basic importance is attached to the natural vibration frequency corresponding to the first bending mode. The multiple first mode is connected to the horizontal shift of a platform or arches, additionally coupled with the deformation corresponding to torsion. In the bridge standards, the first bending mode was adopted as default followed subsequently by higher rank modes of torsional or transversal shapes which do not always occur. This paper describes fourteen numerical models of various arches used in bridge design. The arch bridge, of vertical arches, constitutes a reference. Other models are their varieties through a change of the arch height, a method of connecting platforms and arches at a head and their resulting interaction. Furthermore, variability of arch tilts from a vertical plane was discussed. Conclusions are not unanimously final from the technical point of view; nevertheless, certain beneficial solutions, corresponding to the models of structures of higher natural frequencies, can be indicated.
In Poland, the ecological corridor map overlaps with forests, as well as with the road network. T... more In Poland, the ecological corridor map overlaps with forests, as well as with the road network. The police have recorded near a 100% increase in animal mortality over the last decade. In most cases, bridges automatically serve as passages for animals, even if they have not been considered and designed for such a role. The following facts are importand: silence is positive for animals, natural guides are better then fences and walls, gentle lighting moderates car lights at night. Therefore, the semi-transparent canopy-type noise screens should be used, as well as olfactory tracks. The solution proposed here is beneficial for both the environment and road users. For the proper functioning of the bridge, it is crucial to take into consideration that animals are more efficiently guided by their smell than by channelling fences. However, the commonly used fences would also be provided. Olfactory traces can come in two kinds: animal faecal matter and mating scents. In a natural habitat, ...
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Papers by Slawomir Karas