Filtry
wszystkich: 918
wybranych: 815
Wyniki wyszukiwania dla: REBUILT AFTER WAR DAMAGE
-
Multipoint Ultrasonic Diagnostics System of Prestressed T-Beams
PublikacjaThis paper is devoted to the application of ultrasonic wave propagation phenomena for the diagnostics of prestressed, concrete, bridge T-beams. A multi-point damage detection system is studied with use of numerically obtained data. The system is designed to detect the presence of the material discontinuities as well as their location.
-
Architectural Symbols of a City – Case Study
PublikacjaThe identity of a city is understood as a collection of individual features, which give the city its individual character and distinguish it from other places; it undoubtedly constitutes a cultural value, which should be cherished. In the case of Sopot – a spa located on the Bay of Gdansk, the mosaic of its geographical location, landscape values, urban layout and historic architecture has created a unique image of a seaside resort....
-
Experimental Study on Pounding between Structures during Damaging Earthquakes
PublikacjaMutual pounding between structures during earthquakes may cause serious structural damage. The aim of this paper is to show the results of a shaking table experimental study focused on pounding between structures in series under several earthquake excitations. The experiments were performed using three tower models with different configurations and different gap distances between them. In the first stage of the study, one rigid...
-
Architektura pomników poświęconych ofiarom ataków terrorystycznych jako kontynuacja realizacji komemoratywnych kształtowanych w postpamięci
Publikacjaarchitecture of Memorials Dedicated to the Victims of terrorist attacks as a continuation of commemorative Structures created within Post-memory Having the rich art of commemorating events of the Second World War as a key reference, this article will try to show how contemporary architectural interven- tions in public space make attempts to respond to the social need of dealing with traumatic events and formulating a new attitude...
-
Space and spatial practices in times of confinement. Evidence from three European countries: Austria, France and Poland
PublikacjaIn the first half of 2020, millions of people were subjected to drastic restrictions aimed at limiting the spread of the Covid-19 disease. Austria, France and Poland have implemented a lockdown to varying degrees and for varying lengths of time. This is an unprecedented situation in Europe: until now, even in times of war, curfew measures have never been applied 24 h a day. The research presented in this article was carried out...
-
Detection of Closing Crack in Beam Based on Responses Induced by Harmonic Excitation
PublikacjaThe non-linear contact model was chosen to simulate the closed crack in the cantilever beam. The study examines the shape and characteristics of the phase diagram of a cantilever beam with closed cracks. It investigates how various crack properties influence the geometry of the phase diagram and proposes a method for identifying cracks based on their features. The area of each closed curve in the phase diagram is determined using...
-
Microscale diamond protection for a ZnO coated fiber optic sensor
PublikacjaFiber optic sensors are widely used in environmental, biological and chemical sensing. Due to the demanding environmental conditions in which they can be used, there is a risk of damaging the sensor measurement head placed in the measuring field. Sensors using nanolayers deposited upon the fiber structure are particularly vulnerable to damage. A thin film placed on the surface of the fiber end-face can be prone to mechanical damage...
-
Debonding Detection in Reinforced Concrete Beams with the Use of Guided Wave Propagation
PublikacjaOne of the most frequent damage of the reinforced concrete structures is debonding between steel bar and concrete cover. In the case of debonding occurrence not only the strength of the structure decreases, but also it is more vulnerable to corrosion damages. For this reason fast and effective methods of debonding detection in an early stage of its development need a significant boost. The paper presents analytical and experimental...
-
Thermal Imaging Aided Assessment of a State of Equipment Under Test and its Protecting Elements
PublikacjaIn the paper the investigation results using thermal imaging methods are presented. The examined is a state of equipment under test and its protecting components. The estimations are done for the chosen protecting elements during surge immunity testing. The results show that the thermal imaging methods are useful for early detection of possible damage of a device being tested
-
Influence of IED Explosion on Lateral Dynamics of a Vehicle
PublikacjaThe paper describes field test results of heavy vehicle tire blow-outs. Both civilian and military vehicles are subjected to sudden loss of inflation pressure in one or more wheels, often accompanied by serious tire damage. Selected results related to the lateral dynamic of vehicle during and just after explosive tire destruction are reported
-
Western Front of the City Centre of Gdańsk. An Urban Conservation Study
PublikacjaThe western front of Gdańsk`s city centre is the key fragment of a ring road scheme, which was created at the turn of the 20th century during the great transformation of the city. It was at that time that new streets and squares were delineated on the site of the early modern earthen bastions, which for more than three centuries marked Gdańsk`s border. The new city development was set up in their surroundings. In 1945, Gdańsk was...
-
Dzielnica Reprezentacyjna Gdyni i jej powojenne oraz współczesne interpretacje
PublikacjaThe concept of the Premiere District in Gdynia was first conceived in the 1920s and from that time on it constantly accompanied the history of the city. It derivated from the idea of creating a symbol of Poland's regaining independence after the first World War and the successful creation of the new port and city on the Baltic coast. As the result of that development, Gdynia was named the maritime capital of Poland and was treated...
-
Wave Method for Structural Health Monitoring: Testing Using Full-Scale Shake Table Experiment Data
PublikacjaAn algorithm of the wave method for structural health monitoring (SHM) is tested and calibrated using shake table experiment data of a full-scale, seven-story, reinforced-concrete building slice. The method is based on monitoring changes in the velocity of waves propagating vertically through the structure, identified by least-squares (LSQ) fit of beam models. The experiment was conducted by a team from the University of California,...
-
Experimental and theoretical study on high-temperature creep of VT6 titanium alloy under multi-axial loading conditions
PublikacjaIn the framework of damage mechanics, we discuss a new mathematical model that describes the kinetics of the stress–strain state and damage accumulation during material degradation by the mechanism of long-term strength under complex multiaxial stress state. An experimental and theoretical technique is proposed for determination of material parameters and scalar constitutive functions for damaged media based on specially set experiments...
-
Failure Monitoring and Condition Assessment of Steel-Concrete Adhesive Connection Using Ultrasonic Waves
PublikacjaAdhesive bonding is increasingly being incorporated into civil engineering applications. Recently, the use of structural adhesives in steel-concrete composite systems is of particular interest. The aim of the study is an experimental investigation of the damage assessment of the connection between steel and concrete during mechanical degradation. Nine specimens consisted of a concrete cube and two adhesively bonded steel plates...
-
Eulerian motion magnification applied to structural health monitoring of wind turbines
PublikacjaSeveral types of defects may occur in wind turbines, as physical damage of blades or gearbox malfunction. A wind farm monitoring and damage prediction system is built to observe abnormal vibrations of elements of wind turbine: blades, nacelle, and tower. Contactless methods are developed which do not require turbine stopping. In this work, structural health monitoring of a wind turbine is evaluated using a conversion from the captured...
-
Simulations of air and water flow in a model dike during overflow experiments
PublikacjaFlow in flood dikes, earth dams, and embankments occurs in variably saturated conditions, with pores of the earth material filled partly with water and partly with air. In routine engineering analysis, the influence of pore air is neglected and the air pressure is assumed equal to atmospheric. In some circumstances, for example, during overtopping of the dike by water, the effect of pore air on water flow and stability of the structure...
-
Silver nanoparticles induce premutagenic DNA oxidation that can be prevented by phytochemicals from Gentiana asclepiadea
PublikacjaAmong nanomaterials, silver nanoparticles (AgNPs) have the broadest and most commercial applications due to their antibacterial properties, highlighting the need for exploring their potential toxicity and underlying mechanisms of action. Our main aim was to investigate whether AgNPs exert toxicity by inducing oxidative damage to DNA in human kidney HEK 293 cells. In addition, we tested whether this damage could be counteracted...
-
Baseline-free debonding detection in reinforced concrete structures by elastic wave propagation
PublikacjaThe article presents the results of the numerical and experimental analysis concerning wave propagation in reinforced concrete (RC) beams with various extent of debonding between the steel rod and concrete cover. The main aim of the paper was to consider the unsolved research gaps, which considerably limit the application of wave-based methods in practice. The propagation of the flexural wave modes excited and registered on the...
-
Comparison of safety levels required by adequate regulations for cargo ships of different types
PublikacjaDuring the currently ongoing development of methods for assessing the safety of ships, it is imperative that a compromise between the accuracy of the results and the accessibility of obtaining results is reached. This paper shows the calculations of a theoretical hull against damage stability regulations as included in SOLAS 2020, ICLL 66/88 as amended in 2003 and MARPOL 78. The rules included in the currently valid regulations require...
-
Modelling reinforced concrete beams under mixed shear-tension failure with different continuous FE approaches
PublikacjaThe paper presents quasi-static numerical simulations of the behaviour of short reinforced concrete beams without shear reinforcement under mixed shear-tension failure using the FEM and four various constitutive continuum models for concrete. First, an isotropic elasto-plastic model with a Drucker-Prager criterion defined in compression and with a Rankine criterion defined in tension was used. Next, an anisotropic smeared crack...
-
Experimental and computational study on mechanical behaviour of carpentry corner log joints
PublikacjaThis work concerns experimental and numerical research on carpentry joints used in historic wooden buildings in southeastern Poland and western Ukraine. These structures are mainly sacred buildings, and the types of corner log joints characteristic of this region are primarily saddle-notch and dovetail joints; thus, these two types of joints were analysed in this study. The modelling of historic timber structures is a complex...
-
Features of load and wear of main propulsion devices on sea-going ships with piston combustion engines and their impact on changes in technical states of the systems
PublikacjaThe paper presents the specificity of operation of propulsion systems of seagoing ships which causes the need to control the load on them, especially on their engines called main engines. The characteristics of the load on the propulsion systems, especially on the main engines as well as on the shaft lines and propellers driven by the engines, along with the process of wear in tribological joints (sliding tribological systems)...
-
Identification of defected sensors in an array of amperometric gas sensors
PublikacjaPurpose Amperometric gas sensors are commonly used in air quality monitoring in long-term measurements. Baseline shift of sensor responses and power failure may occur over time, which is an obstacle for reliable operation of the entire system. The purpose of this study is to check the possibility of using PCA method to detect defected samples, identify faulty sensor and correct the responses of the sensor identified as faulty. Design/methodology/approach In...
-
The Application of Dynamic Electrochemical Impedance Spectroscopy (DEIS) Technique in Corrosion and Corrosion Inhibition Studies
Publikacjaorrosion studies have attracted considerable interest in the areas of materials chemistry and industrial chemistry, as it affects the direct and indirect costs of industry, leading to huge economic setbacks due to the need for repair, maintenance, and even shutdowns due corrosion damage. This new volume is a comprehensive resource that presents new and up-to-date, theoretical, and experimental corrosion inhibition studies.
-
Emergency condition of the ceramic facade of a residential building
PublikacjaThe paper presents a description of the technical condition of the ceramic cladding of a residential building, the technical condition of which deteriorated significantly after only a few years of operation. The analysis of the influence of the applied design and working solutions on the façade failure frequency was analyzed. The article presents a conceptual solution to bring the building to the proper technical condition in terms...
-
Emergency condition of the ceramic facade of a residential building
PublikacjaThe paper presents a description of the technical condition of the ceramic cladding of a residential building, the technical condition of which deteriorated significantly after only a few years of operation. The analysis of the influence of the applied design and working solutions on the façade failure frequency was analyzed. The article presents a conceptual solution to bring the building to the proper technical condition in terms...
-
Trolleybus with traction batteries for autonomous running
PublikacjaIn 2009 the transport company of city Gdynia (Poland) introduced in the operation trolleybuses fitted with traction batteries. This solution was designed for emergency situations, such as: damage of overhead lines or power loss. Transport company also considering the use of batteries in regular use. The article presents the operational experiences gained during the current operation. Furthermore, there are presented new trends...
-
Trolleybuses with traction batteries for autonomous running
PublikacjaIn 2009 the transport company of city Gdynia (Poland) introducet in the operation trolleybuses fitted with traction batteries. This solution was designed for emergency situations, such as: damage of overhead lines or power loss. Transport company also considering the use of batteries in regular use. The article presents the operational experiences gained during the current operation. Furthermore, there are presented new trends...
-
Żuławski dom podcieniowy - przykłady i skala współczesnych działań konserwatorskich
PublikacjaPoczątki zainteresowania architekturą regionalną na terenach Prus Zachodnich sięgają przełomu XIX/XX wieku i związane są z osobą Bernharda Schmida. Koniec II wojny światowej przyniósł na Żuławach zniszczenie ponad 2 744 zagród chłopskich. Ze względu na priorytet ratowania zabytków Gdańska, historyczne obiekty z okolicznych wsi doczekały się szerszej uwagi służb konserwatorskich dopiero w połowie lat pięćdziesiątych. Opracowanie...
-
Wodociągi Gdyni, (1911-1961)
PublikacjaMonografia zawiera informacje faktograficzne o procesie tworzenia i eksploatacji wodociągów w latach 1911 – 1961: wiejskiego (Oksywie), osiedlowego (Kamienna Góra), miejskiego (Śródmieście, Grabówek)) oraz grupowego na obszarze Wielkiej Gdyni. Dla każdego wodociągu udokumentowano przebieg prac organizacyjno-przygotowawczych, koncepcje projektowe i wykonane roboty budowlano-instalacyjne. Zagadnienia techniczne przedstawiono na tle...
-
Stan awaryjny wiaduktu kolejowego w Bydgoszczy
PublikacjaW pracy przedstawiono opis stanu awaryjnego wiaduktu kolejowego. Omówiono wyniki badań in situ oraz teoretycznych analiz statyczno-wytrzymałościowych ponad 100-letniego obiektu. Przedstawiono wnioski i zalecenia dotyczące doraźnego zabezpieczenia obiektu oraz warunki jego dalszej eksploatacji.
-
Stan awaryjny wiaduktu kolejowego w Bydgoszczy
PublikacjaW pracy przedstawiono opis stanu awaryjnego wiaduktu kolejowego. Omówiono wyniki badań in situ oraz teoretycznych analiz statyczno-wytrzymałościowych ponad 100-letniego obiektu. Przedstawiono wnioski i zalecenia dotyczące doraźnego zabezpieczenia obiektu oraz warunki jego dalszej eksploatacji.
-
Behaviour of Asymmetric Structure with Base Isolation Made of Polymeric Bearings
PublikacjaEarthquake-induced ground motions are the most severe and unpredictable threats to the structures all around the world. Seismic excitations cause a lot of damage in a wide variety of ways, leaving thousands of casualties in their wake. Due to randomness of earthquake occurrence, lack of visible causes and their power of destructiveness, structural engineers need to develop new technical solutions and protection systems against...
-
Impact Behaviour of Glass Fribre /Epoxy Composites with Nano-Enhanced Resin after Water Exposure
PublikacjaImpact behaviour of glass fibre /epoxy composites with nano- SiO2 modified resin was studied in terms of low velocity impact after water exposure. Nanocomposites with 1%, 2%, 3% 5% 7% nano-SiO2 (Nanopox- Evonic) were investigated. Peak impact load and impact damage area as a function of nanoparticle contents were compared for dry specimens and for samples exposed to water (0.7 %wt. 1.7% water absorbed) at 1J, 2J 3J impact energies....
-
Detection and Imaging of Debonding in Adhesive Joints of Concrete Beams Strengthened with Steel Plates Using Guided Waves and Weighted Root Mean Square
PublikacjaStrengthening of engineering structures is an important issue, especially for elements subjected to variable loads. In the case of concrete beams or slabs, one of the most popular approaches assumes mounting an external reinforcement in the form of steel or composite elements by structural adhesives. A significant disadvantage of adhesive joints is the lack of access to the adhesive film for visual condition assessment, thus, there...
-
Civil liability for artificial intelligence products versus the sustainable development of CEECs: which institutions matter?
PublikacjaThe aim of this paper is to conduct a meta-analysis of the EU and CEECs civil liability institutions in order to find out if they are ready for the Artificial Intelligence (AI) race. Particular focus is placed on ascertaining whether civil liability institutions such as the Product Liability Directive (EU) or civil codes (CEECs) will protect consumers and entrepreneurs, as well as ensure undistorted competition. In line with the...
-
Revitalization of Sopot - The Seaside Spa Town in Poland
PublikacjaSopot is a Polish seaside resort. In the past - as early as at the beginning of the 20th century - this town was famous for the healing opportunities they created: good conditions for resting and recreation. This town was places where everyone with enough selfesteem was willing to be seen. Since the post-war reconstruction until 1989 (establishment of local governments in Poland), not much has happened in Polish cities in terms...
-
Fatigue behaviour of SLM maraging steel under variable-amplitude loading
PublikacjaOne of the most challenging issues for additive manufactured materials is fatigue endurance. Engineering components often operate under complex, variable amplitude loadings, in which existing technological imperfections promote fatigue cracks growth and damage of elements eventually. In this study the effects of different variable-amplitude strain levels on fatigue life, 18Ni300 steel was tested. The work presents various behaviours...
-
VIBRATION DIAGNOSTICS OF FOOTBRIDGE WITH USE OF ROTATION SENSOR
PublikacjaThe benefits of the additional measurement of rotational degrees of free-dom on the performance of the vibration diagnosis of bridges are studied in this paper. The common vibrational diagnostics that uses translational degrees of freedom is extended by measurements of rotations. The study is curried out on a footbridge and the presence of damage as well as its location and size is determined with use of FEM updating procedure....
-
Przedwojenne wydawnictwa Stowarzyszenia Elektryków Polskich w bibliotekach i bibliotekach cyfrowych
PublikacjaArtykuł przedstawia krótką historię piśmiennictwa z dziedziny elektrotechniki. Po 1918 r. obserwuje się wzrost liczby publikacji, a wraz z rozwojem nauki zwiększa się obszar tematyczny literatury fachowej. Ogromną zasługę w tym rozwoju miało Stowarzyszenie Elektryków Polskich. W artykule pokazano sposoby wyszukiwania wydawnictw przedwojennych SEP, ich dostępność w bibliotekach, także cyfrowych. Przedstawia w jaki sposób zwiększyć...
-
A simplified method to assess the impact of ship-to-ship collision on the risk of tanker ship hull girder breaking accounting for the effect of ageing
PublikacjaOne of the most critical structural failures is the exceedance of the ship hull girder’s ultimate strength, which may result in hull breaking, and subsequent severe consequences, including loss of life and property as well as environmental damage in case of an oil spill. A cause for such loss of structural continuity can be triggered by a collision with another vessel. In addition, the ageing mechanisms of the hull structure could...
-
Consideration of Pseudo Strain Energy in Determination of Fatigue Life and Microdamage Healing of Asphalt Mastics
PublikacjaRest periods between cyclic loads can lead to recovery of damage and extension of fatigue life. This phenomenon is referred to as healing. Healing is clearly observed in bituminous materials, such as asphalt mastics, which belong to the components of asphalt mixtures. Due to the nature of road pavement traffic loading, which is characterized by series of intermittent pulses with rest periods, consideration of healing is necessary...
-
EXPERIMENTAL ANALYSIS OF RUBBER AND STYROFOAM BUMPERS INFLUENCE ON THE COLLIDING STRUCTURES
PublikacjaPast and recent investigations of colliding structures under seismic excitation confirmed that pounding may have a significant influence on the structural response. Interactions between adjacent buildings may cause serious damage to the structures, leading even to its total collapse. The main reason of earthquake-induced pounding, besides insufficient distance between structures, are differences in stiffness or mass of colliding structures....
-
INNOVATIVE RUN FLAT SYSTEMS
PublikacjaOne of the most essential threats to the mobility of wheeled vehicles is their relatively high sensitivity to tire damage. Tires can be damaged as a result at vehicle-targeting fire, after running on a mine or an improvised charge. The purpose of the article is to analyze the current technical solutions in wheeled vehicle tires, allowing for the unobstructed use of the vehicle despite the damage of one or several tires (RUN FLAT...
-
FEM analysis of composite materials failure in nonlinear six field shell theory
PublikacjaThe monography deals with the problem of failure initiation in thin laminated composites. Known techniques of laminate structures modelling are briefly characterised. Eventually, shell based approach is chosen for the purpose of the description of the composite structures behaviour, as it predicts their deformation and states of stress effectively in a global sense. The nonlinear six parameter shell theory (6p theory) with asymmetric...
-
Estimation of Failure Initiation in Laminated Composites by means of Nonlinear Six-Field Shell Theory and FEM
PublikacjaThe monography deals with the problem of failure initiation in thin laminated composites. Known techniques of laminate structures modelling are briefly characterised. Eventually, shell based approach is chosen for the purpose of the description of the composite structures behaviour, as it predicts their deformation and states of stress effectively in a global sense. The nonlinear six parameter shell theory (6p theory) with asymmetric...
-
Quality Evaluation of Voice Transmission Using BPL Communication System in MV Mine Cable Network
PublikacjaThis article presents results of a quality evaluation study, considering voice transmission in a 6 kV medium voltage cable network using the BPL (Broadband over Power Line) communication system. The tests are carried out under real mining conditions for the selected power cable without voltage, earthed at both sides. Such a method of monitoring work conditions is of great importance, especially during a disaster. Power cables are...
-
A framework for onboard assessment and monitoring of flooding risk due to open watertight doors for passenger ships
PublikacjaPost-accident safety of ships is governed by damage stability, affected by watertight subdivisions which limit accidental flooding. This is important for passenger ships with watertight doors (WTDs) often fitted in the bulkheads. Awareness of the ship flooding risk due to open WTDs and the conditions under which the associated risk level changes are prerequisites for proactive risk mitigation. Accident risk is often expressed as...
-
Badanie stanu nawierzchni drogowej z wykorzystaniem uczenia maszynowego
PublikacjaW artykule opisano budowę systemu informowania o stanie nawierzchni drogowej z wykorzystaniem metod cyfrowego przetwarzania obrazów oraz uczenia maszynowego. Efektem wykonanych prac badawczych jest eksperymentalna platforma, pozwalająca na rejestrację uszkodzeń na drogach, system do analizy, przetwarzania i klasyfikacji danych oraz webowa aplikacja użytkownika do przeglądu stanu nawierzchni w wybranej lokalizacji.