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Spękania nawierzchni z podbudową mieszanki mineralno-cementowo-emulsyjnej na przykładzie drogi krajowej nr 7
PublikacjaW artykule przedstawiono szczegółowy opis badań nawierzchni, niezbędnych do określenia prawdopodobnych przyczyn powstawania spękań poprzecznych nawierzchni drogi krajowej nr 7 na odcinku od Gdańska do Kiezmarka, stwierdzonych w 2006r.
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Badanie możliwości stosowania kompozytów popiołowo-cementowych z włóknami szklanymi i stalowymi w warunkach zagrożenia korozją chlorkową.
PublikacjaCelem pracy jest zbadanie wpływu modyfikacji drobnoziarnistych kompozytów popiołowo-cementowych dodatkiem niewielkich ilości włókienszklanych i stalowych na ich właściwości techniczne i odpornoiść na korozję chlorkową. Ograniczenie ilości cementu oraz zastąpienie znacznej części kruszywa popiołem lotnym i dodatek włókien losowo roproszonych stanowi próbe uzyskania ochrony materiałowo-strukturalnej przed korozją.
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Analiza doświadczalna i numeryczna paneli warstwowych z okładzinami z płyty cementowo-magnezjowej i rdzeniem z polistyrenu ekspandowanego
PublikacjaPanele warstwowe są chętnie stosowane w budownictwie ze względu na wysoki stosunek wytrzymałości do masy, oraz łatwość i szybkość montażu. Idea przekroju warstwowego polega na łączeniu cienkich i wytrzymałych okładzin z lekkim rdzeniem. Dobór materiałów składowych pozwala na swobodę kształtowania cech paneli. W rozprawie opisano panele z okładzinami z płyty cementowo magnezjowej i rdzeniem z polistyrenu ekspandowanego, charakteryzujące...
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Results of wettability evaluation of acrylic bone cements incorporating various components
Dane BadawczeThe database contains the images of the contact angle measurements of modified bone cements using the optical tensiometer. The following modifications were evaluated: the addition of biodegradable components (including chitosan, cellulose, tricalcium phosphate, polydioxanone or magnesium), the addition of bioactive components (bioglasses) or the addition...
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Results of microhardness measurements of acrylic bone cements incorporating various components
Dane BadawczeThe database contains the images of microhardness measurements of modified bone cements using the Vickers Hardness Tester. The following modifications were evaluated: the addition of biodegradable components (including chitosan, cellulose, tricalcium phosphate, polydioxanone or magnesium), the addition of bioactive components (bioglasses) or the addition...
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Results of OM examination of acrylic bone cements incorporating various components
Dane BadawczeThe database contains the images of the microstructure of modified bone cements observed on the cross-section with the optical microscope (OM). The following modifications were evaluated: the addition of biodegradable components (including chitosan, cellulose, tricalcium phosphate, polydioxanone or magnesium), the addition of bioactive components (bioglasses)...
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Results of AFM examination of acrylic bone cements incorporating various components
Dane BadawczeThe database contains the images of the surface topography of modified bone cements observed with the atomic force microscopy (AFM). The following modifications were evaluated: the addition of biodegradable components (including chitosan, cellulose, tricalcium phosphate, polydioxanone or magnesium), the addition of bioactive components (bioglasses)...
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Results of SEM examination of acrylic bone cements incorporating various components
Dane BadawczeThe database contains the images of the microstructure of modified bone cements observed with the scanning electron microscope (SEM). The following modifications were evaluated: the addition of biodegradable components (including chitosan, cellulose, tricalcium phosphate, polydioxanone or magnesium), the addition of bioactive components (bioglasses)...
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Stowarzyszenie Producentów Cementu
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PLUTONIUM Opracowanie nowego wstrzykiwalnego ceramiczno-polimerowego cementu kostnego
ProjektyProjekt realizowany w Zakład Technologii Biomateriałów zgodnie z porozumieniem 3/2022/IDUB/III.4.3/Pu z dnia 2022-05-09
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TECHNETIUM Opracowanie nowego cementu kostnego na bazie fosforanu magnezu dedykowanego jako degradowalny substytut kości
ProjektyProjekt realizowany w Zakład Technologii Biomateriałów zgodnie z porozumieniem 14/2022/IDUB/III.4.1/Tc z dnia 2022-04-12
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Wpływ zmiennych warunków obciążenia na charakterystyki zmęczeniowe kompozytów cementowo-bitumicznych wykonanych w technologii recyklingu na zimno
ProjektyProjekt realizowany w Katedra Inżynierii Transportowej
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Wpływ chemiczny frakcji mikrosfer glinokrzemianowych na zależność pomiędzy wydzielonym ciepłem wczesnej hydratacji a wytrzymałością na ściskanie zapraw cementowych
ProjektyProjekt realizowany w Katedra Wytrzymałości Materiałów
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- Opracowanie złożonych struktur nanometrycznych do kształtowania właściwości osłonowych i reologicznych mieszanek stosowanych w technologii druku 3D kompozytów cementowych
ProjektyProjekt realizowany w Zachodniopomorski Uniwersytet Technologiczny w Szczecinie zgodnie z porozumieniem 2020/39/D/ST8/00975 z dnia 2021-07-14
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Marcin Wekwejt dr inż.
OsobyMarcin Wekwejt, absolwent studiów inżynierskich w inż. biomedycznej (2016; Politechnika Bydgoska im. J. i J. Śniadeckich & Collegium Medicum im. L. Rydygiera), studiów magisterskich w inż. mechaniczno-medycznej (2018; Politechnika Gdańska & Gdański Uniwersytet Medyczny) oraz studiów doktoranckich w dyscyplinie inż. materiałowej (2021, Politechnika Gdańska). Uzyskał z wyróżnieniem stopień naukowy doktora nauk inżynieryjno-technicznych...
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Mechanical properties of two-stage concrete modified by silica fume
PublikacjaAbstract. Two-stage concretes, despite the fact that they have proven themselves in various types of construction, have not been studied to the same extent as traditional heavy concretes. Therefore, the article developed the composition of frame concrete with various additives in the composition of the cement-sand mortar. A comparison of the mechanical characteristics of the developed compositions with the addition of silica fume...
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Polish experience with cold in-place recycling
PublikacjaDeep cold in-place recycling using cement and asphalt emulsion has been used for reconstruction of existing roads since the beginning of the 1990s. This paper describes the first Polish requirements for mineral-cement-emulsion mixtures. As requirements stated for the strength of the mineral-cement-emulsion mixtures were quite high, most of the mixtures were designed using high amount of cement and aggregate added for the improvement...
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Wykorzystanie tomografii komputerowej przy analizie jakości zacementowania - migracja gazu
PublikacjaArtykuł przedstawia opis zjawiska znanego w wiertnictwie otworowym jako migracja gazu. Opisano główne przyczyny powstawania tego negatywnego zjawiska polegającego na przepływie gazów a także płynów w zaczynie cementacyjnym lub kamieniu cementowym. Przygotowano próbki imitujące zacementowany odcinek rur okładzinowych. Skupiono się na wykorzystaniu tomografii komputerowej, oraz analizie zrekonstruowanego trójwymiarowego obrazu, w...
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The influence of combination of binding agents on fatigue properties of deep cold in-place recycled mixtures in Indirect Tensile Fatigue Test (ITFT)
PublikacjaThe publication presents fatigue properties of cold recycled mixtures for eight combinations of binding agents (cement and bituminous emulsion). Cold recycled mixtures were evaluated in Indirect Tensile Fatigue Test (ITFT) at the temperature of 20 C in controlled stress mode. As a function of horizontal stress, fatigue life is strongly influenced by combination of the binding agents. When fatigue life is analyzed as a function...
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Measurements of the heat of hydration released by concrete specimens cured under adiabatic conditions
Dane BadawczeThe DataSet contains measurements of heat of hydartion of concrete cubes (150 x 150 x 150 mm) cured under adiabatic conditions. The specimens were moulded from six types of concrete mixtures produced in the laboratory conditions. Mix #1: Portland cement CEM I 42.5R and gravel aggregate, mix #2: CEM I 42.5R and basalt aggregate, mix#3: Portland-composite...
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Evaluation of the stiffness modulus and phase angle of cold in-place recycled mix-tures for long curing periods
PublikacjaArticle presents the changes inbehaviour of cold-in place recycling mixtures made using cement and bituminous emulsion (CIR mixtures) after anelongated time of curing. Most of the available literatureregarding change instiffness modulus and phase angle presents resultsfor a maximum of several dozen days,which makesit difficult to predict the behaviour over the whole life of the compacted layer. The article...
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Assessment of the application of CEM III with exposed aggregate as an alternative to CEM I for road pavements
PublikacjaThe article presents a results of study on the impact of replacing CEM I SR3/NA by CEMIII/A LH/HSR/NAon the mechanical properties and durability of pavement concrete with exposed aggregate. Was used granite aggregate and washed sand. Water/cement () ratio in the tested concretes constituted 0.35 and 0.4 and part of the cement was replaced with a 5% addition of natural pozzolana – zeolite. Compressive strength tests were performed...
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Modelling hydraulic and capillary-driven two-phase fluid flow in unsaturated concretes at the meso-scale with a unique coupled DEM-CFD technique
PublikacjaThe goal of the research was to demonstrate the impact of thin porous interfacial transition zones (ITZs) between aggregates and cement matrix on fluid flow in unsaturated concrete caused by hydraulic/capillary pressure. To demonstrate this impact, a novel coupled approach to simulate the two-phase (water and moist air) flow of hydraulically and capillary-driven fluid in unsaturated concrete was developed. By merging the discrete...
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Palm Oil Fuel Ash-Based Eco-Efficient Concrete: A Critical Review of the Short-Term Properties
PublikacjaThe huge demand for concrete is predicted to upsurge due to rapid construction developments. Environmental worries regarding the large amounts of carbon dioxide emanations from cement production have resulted in new ideas to develop supplemental cementing materials, aiming to decrease the cement volume required for making concrete. Palm-oil-fuel-ash (POFA) is an industrial byproduct derived from palm oil waste’s incineration in...
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Effect of soil moisture on current-carrying capacity of low-voltage power cables
PublikacjaOne of the factors affecting current-carrying capacity of underground power cables is the thermal resistivity of soil. Its value in the close proximity of the cable is the most important, and for this reason, in some cases, the local soil is replaced with an another soil type or with a cement-sand mixture. The thermal resistivity of the soil is strongly affected by moisture, and in the case of a cement-sand mixture – as tested...
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Structural Design and Sensitivity Analysis of Semi-Rigid Pavement of a Motorway
PublikacjaThis paper presents application of mechanistic-empirical methods in design of semi-rigid pavement for a section of a motorway in Poland. The stage construction was assumed. Three fatigue criteria were applied in the design. For asphalt fatigue cracking and subgrade soil the criteria from the Asphalt Institute (1981) were applied. For fatigue cracking of cement stabilized bases the Dempsey (1984) and De Beer (1992) criteria were...
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The Effect of Fly Ash Microspheres on the Pore Structure of Concrete
PublikacjaThe fly ash microspheres (FAMs) formed during the mineral transformation stage in coal combustion are hollow spherical particles with a density less than water. This paper presents the results of X‐ray micro‐computed tomography and an automatic image analysis system of the porosity in the structure of hardened concrete with microspheres. Concrete mixtures with ordinary Portland cement and two substitution rates of cement by microspheres—5%...
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Analiza nośności zabytkowych fundamentów w kontekście jakości użytych zapraw Analysis of the Load-Bearing Capacity of Historical Foundations in the Context of the Quality of Mortar Used
PublikacjaStructures of historical buildings usually have the form of masonry elements. The weakest component of such elements is mortar, especially in stone foundations, which were often used in the with a focus on the modeling of mortar as a joint connecting stones in a characteristic medieval foundation. Different types of mortar: cement, cement-lime, lime and gypsum mortars, were examined. A numerical analysis was carried out on the...
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Preliminary study of linear viscoelasticity limits of cold recycled mixtures determined in Simple Performance Tester (SPT)
PublikacjaThe publication presents methodology developed for determination of linear viscoelasticity limits for cold recycled mixtures with cement and bituminous emulsion using Simple Performance Tester (SPT). Methodology was verified on reference materials (PCV and steel dummy specimens, cement concrete and asphalt concrete) to comply with elasticity and viscoelasticity theory. The developed methodology enabled determination of linear viscoelasticity...
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Mesoscopic simulations of crack propagation in concrete using cohesive elements
PublikacjaThe paper presents results of two-and three-dimensional meso-scale simulations of fracture in notched concrete beams subjected to three-point bending test. Concrete was assumed as a 3-phase material composed of aggregate grains placed in the cement matrix with Interfacial Transitional Zones (ITZs) between then. In 2D simulations macro-voids were also taken into account. The particle distribution was taken from real concrete beams...
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Concrete temperature measurements of cubic specimens cured under isothermal and semi-adiabatic conditions
Dane BadawczeThe DataSet contains temperature measurements of concrete cubes (150 x 150 x 150 mm) cured under isothermal and semi-adiabatic conditions. The specimens were moulded from six types of concrete mixtures produced in the laboratory conditions. Mix #1: Portland cement CEM I 42.5R and gravel aggregate, mix #2: CEM I 42.5R and basalt aggregate, mix#3: Portland-composite...
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Structural design and sensitivity analysis of semi-rigid pavement of a motorway
PublikacjaThis paper presents application of mechanistic-empirical methods in design of semi-rigid pavement for a section of a motorway in Poland. The stage construction was assumed. Three fatigue criteria were applied in the design. For asphalt fatigue cracking and subgrade soil the criteria from the Asphalt Institute (USA) were applied. For fatigue cracking of cement stabilized bases the Dempsey (USA) and De Beer (South Africa) criteria...
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CONCRETE MIX DESIGN USING ABRAMS AND BOLOMEY METHODS
PublikacjaOne way to reduce the consumption of cement is to optimize its use. Many known methods of concrete design, based on the Abrams law and the Bolomey method. Therefore, the authors chose those methods for analysis. The concrete composition with the assumed strength class, calculated by any method differs significantly. This applies especially to the cement content, as its content in the composition of concrete varies from 20 to 50%....
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The Influence of the Aircraft Operating Fluids on the Mechanical Parameters of the Airport Surface Concrete
PublikacjaThe authors of the article assessed the impact of operating fluids used to service aircraft on changing mechanical parameters of cement concrete intended for airport pavement. The research concerned concrete designed with the use of CEM I 42.5N LH NA low-alkali cement, broken granite aggregate, fine washed aggregate, and admixtures. The analysis included the assessment of changes in dierences in endurance parameters over various...
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Isothermal Calorimetry and Compressive Strength Tests of Mortar Specimens for Determination of Apparent Activation Energy
PublikacjaThe hydration process of cementitious materials involves a thermally activated reaction that depends on the composition of the mixture and the curing temperature. The main parameter affecting the temperature variation of cast-in-place concrete is the apparent activation energy, which can be used for the efficient prediction of the temperature evolution and maturity index of hardening concrete. This paper discusses two methods to...
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Two-dimensional simulations of concrete fracture at aggregate level with cohesive elements based on X-ray lCT images
PublikacjaThe paper presents results of two-dimensional meso-scale simulations of fracture in notched concrete beams subjected to three-point bending test. Concrete was assumed as a 4-phase material composed of aggregate grains placed in the cement matrix, interfacial transitional zones (ITZs) and macro-voids. The particle distribution was taken from real concrete beams on the basis of X-ray lCT images. Comprehensive numerical analyses were carried...
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Wpływ mikrosfer-frakcji odpadów paleniskowych na mikrostrukturę i wybrane właściwości uzytkowe
PublikacjaIn this study, the microspheres samples were collected from national power station „Dolna Odra”. In this study, the following materials were used: Portland cement class 32,5R and aggregates of 2-8 and 8-16 fractions and natural sand with a maximum grain size of 2 mm and water. Concrete mixtures were made with microspheres additions of 15%, 25% and 40%. A constant water to binder ratio (w/b) of 0,52 was used throughout the investigation....
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Numerical investigations of discrete crack propagation in Montevideo splitting test using cohesive elements and real concrete micro-structure
PublikacjaThe paper is aimed at accurately predicting the discrete fracture process in concrete specimens under complex stress states in two dimensional (2D) simulations. Plain concrete specimens subjected to Montevideo splitting test (MVD) were used for consideration due to non-negligible shear stresses impact in this type of test. In order to reflect the heterogeneous nature of the concrete, the meso-structure of the samples was included...
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GDP growth in Iran
Dane BadawczeThe economy of the Islamic Republic of Iran is one of the fastest growing in the Middle East. Iran should not only be associated with crude oil industry but also other areas of the economy. The sanctions that hindered oil exports from Iran meant that the authorities had to take measures to increase exports of other products. There was an increase in...
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Structural Assessment of Reinforced Concrete Beams Incorporating Waste Plastic Straws
PublikacjaThe behavior of reinforced concrete beams containing fibers made of waste plastic straws (WPSs) under the three point bending test is examined. The effect of WPS fiber addition on the compressive and split tensile strength is reported. Four concrete mixes were prepared. The control mix PS-0 had a proportion of 1 cement: 1 sand: 2 coarse aggregate and a water cement ratio of 0.4. In the other three mixes PS-0.5, PS-1.5 and PS-3,...
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Concrete mix design using machine learning
PublikacjaDesigning a concrete mix is a process of synthesizing many components, it is not a simple process and requires extensive technical knowledge. The design process itself focuses on obtaining the required strength of concrete. Very often designing a concrete mix takes into account the need to maintain the proper water-demand and frost-resistance features. The parameters that influence the concrete class most significantly are the...
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Proceedings of the fib Symposium 2019: Concrete - Innovations in Materials, Design and Structures 2019
PublikacjaDesigning a concrete mix is a process of synthesizing many components, it is not a simple process and requires extensive technical knowledge. The design process itself focuses on obtaining the required strength of concrete. Very often designing a concrete mix takes into account the need to maintain the proper water-demand and frost-resistance features. The parameters that influence the concrete class most significantly are the...
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Determination of metal content in sewage sludge and sewage sludge ash to find opportunities to use them in the construction industry
PublikacjaSewage sludge management is becoming an increasing problem in developed and developing countries. Due to their physicochemical properties (mainly high content of heavy metals) a safe method of utilization is sought. Considering environmental protection, energy recycling, reduction in use of the raw materials and the possibility of immobilization hazardous substances, the use of ashes in building materials becomes a very good way...
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Właściwości gruntów stabilizowanych spoiwami drogowymi w różnym czasie pielęgnacji
PublikacjaW artykule autorzy szukają odpowiedzi na postawionych sobie szereg pytań, m.in.: czy istnieją środki o właściwościach podobnych do spoiwa, jakim jest cement? Czy konieczna jest wymiana gruntów w sytuacji, gdy stabilizacja tradycyjnymi spoiwami nie zdaje egzaminu? Jakie metody badawcze powinny być zastosowane do określenia przydatności poszczególnych spoiw?
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Cold recycled mixtures for binder courses - laboratory evaluation of mechanical properties
PublikacjaCold recycled mixtures composed with cement and bituminous emulsion are nowadays commonly used material for base layer. Typical pavement with cold recycled mixtures usually consists of two asphalt courses (wearing and binding course) constructed over cold recycled base. Therefore the next step in cold recycling is possibility of design of binding courses with recycled materials, but with potential to obtain high quality mixtures...
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Effect of Particle Size of Fly Ash Microspheres (FAMs) on the Selected Properties of Concrete
PublikacjaThis paper presents the investigations of selected properties of concrete containing two fractions of fly ash microspheres (FAMs) with grain size up to 200 μm and up to 500 μm. Concrete mixtures with ordinary Portland cement and three substitution rates of cement by FAMs, 1.3%, 2.0%, and 2.6%, were investigated. For all concrete mixes, the constant water–binder ratio (w/b) equal to 0.50 was used. The research program included the...
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Badania betonów o przyspieszonym twardnieniu
PublikacjaBadania wykazały, że możliwe jest uzyskanie tak wysokich wytrzymałości wczesnych betonów, że całkowicie zbędna staje się ich obróbka termiczna. Stosując odpowiedni cement klasy 42,5R i prawidłowo dobrana mieszankę upłynniającą można uzyskać już po 12 godz. wytrzymałość betonu około 35MPaa przy klasie cementu 52,5R nawet około 50MPa i to przy ilości cementu nie przekraczającej 400 kg/m3 betonu.
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Stiffness of cold-recycled mixtures under variable deformation conditions in the IT-CY test
PublikacjaStiffness modulus belongs to the most important properties describing the cold-recycled mixtures (CRM) in terms of their usability in road pavement structures. Previous research proved that this property is strongly dependent on the scheme and conditions of the test (temperature and time of loading) and the time that has passed since the compaction of the specimen or pavement layer. It is a result of the influence of two different...
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Non-Destructive Assessment of Masonry Pillars using Ultrasonic Tomography
PublikacjaIn this paper, a condition assessment of masonry pillars is presented. Non-destructive tests were performed on an intact pillar as well as three pillars with internal inclusions in the form of a hole, a steel bar grouted by gypsum mortar, and a steel bar grouted by cement mortar. The inspection utilized ultrasonic stress waves and the reconstruction of the velocity distribution was performed by means of computed tomography. The...
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Ultrasonic wave propagation, digital image correlation and X-ray micro-computed tomography measurements of concrete during splitting (cube #1)
Dane BadawczeThe DataSet contains the results of the mechanical behaviour of a concrete cube under the splitting test. The cube had dimensions 70 x 70 x 70 cm3 and was made of concrete with the following ingredients: cement type CEM I 42.5R (330 kg/m3), water (165 kg/m3), aggregate 0/2 mm (710 kg/m3), aggregate 2/8 mm (664 kg/m3), aggregate 8/16 mm (500 kg/m3),...