This paper aims to evaluate experimentally the potentialities of Hybrid Composite Plates (HCPs) t... more This paper aims to evaluate experimentally the potentialities of Hybrid Composite Plates (HCPs) technique for the shear strengthening and repairing of reinforced concrete (RC) beams. HCP is a thin plate of Strain Hardening Cementitious Composite (SHCC) reinforced with Carbon Fiber Reinforced Polymer (CFRP) laminates. For this purpose, an experimental program composed of four Rectangular and five T-cross section beams was executed to assess the strengthening efficiency of HCPs technique. There were two control beams without any type of shear reinforcement, and seven beams strengthened with HCPs. The HCPs were applied to the lateral faces of the beams by using a combination of epoxy adhesive and mechanical anchors. The bolts were applied with a certain torque in order to increase the concrete confinement. To have a better understanding of the shear behavior of SHCC material, Iosipescu shear tests were carried out, and the results were used to derive their fracture mode II parameters. To further explore the potentialities of the HCPs technique for the shear strengthening, the experimental tests were simulated numerically by a FEM-based computer program considering the material properties obtained experimentally. After demonstration of the good predictive performance of the numerical model, a parametric study was executed to investigate the influence of some parameters on the load carrying capacity of the strengthened beams, namely: i) Use a mortar instead of the SHCC; ii) application of different applied torque level to the mechanical anchors; iii) different bond condition between HCPs and concrete substrate.
The first reason why concrete is a very useful material in construction is because of its density... more The first reason why concrete is a very useful material in construction is because of its density and strength. However, they tend to crack and require constant fixing, and this is usually expensive and tiresome. This research aims to investigate the feasibility of employing sodium alginate, a naturally occurring polysaccharide, as an encapsulated self-healing system for concrete. When sodium alginate is applied on concrete, it interacts with the calcium ions in the concrete to create a calcium alginate gel which helps to close up any cracks and also increases the durability of the concrete. The study embraced the usage of sodium alginate, rapeseed oil, calcium chloride, and water hydrate, which were blended with the IKA T25 harmonisation machine. The outcomes of the experiments indicate that self-healing concrete based on sodium alginate has higher durability, and the need for repairs is minimised; thus, the use of sodium alginate in new construction can be considered a promising direction.
The paper is concerned with a numerical homogenization technique for determination of effective m... more The paper is concerned with a numerical homogenization technique for determination of effective material properties of brick masonry in the elastic range. The homogenization problem is posed in the plane state of stress. The corresponding boundary value problem on a representative cell is discretized by the finite element method. The quadrilateral finite element with four nodes and eight degrees of freedom is applied and our own computer program is developed. The homogenization technique allows one to determine for masonry, which is an inhomogeneous two-phase composite medium, an equivalent homogeneous orthotropic material characterized by five material constants. The homogenized material constants can further be used in an analysis of large-scale masonry structures. The obtained results of numerical simulations are compared with predictions of the value of elastic modulus for masonry by other researches, and qualitative agreement can be observed.
Most Lecha w Poznaniu to nazwa obiektu skladającego sie z dwoch niezaleznych, dopelniających sie ... more Most Lecha w Poznaniu to nazwa obiektu skladającego sie z dwoch niezaleznych, dopelniających sie ale pobudowanych w roznych okresach czasu mostow drogowych ─ polnocnego i poludniowego ─ nad rzeką Wartą w ciągu ulic Lechickiej i Baltyckiej. Polnocny Most Lecha jest obecnie w trakcie gruntownej przebudowy (rys. 1, 2). Praca zawiera najwazniejsze informacje związane z obecną przebudową Mostu Lecha, dotyczące m.in. historii obiektu oraz jego znaczenia w ukladzie komunikacyjnym i rozwiązan konstrukcyjnych. Projekt przebudowy Mostu Lecha obejmuje calkowitą rozbiorke istniejącego od 1953 roku mostu, budowe nowego stalowo-betonowego mostu zespolonego w tej samej lokalizacji oraz dostosowanie dojazdow (rys. 1). Obecnie budowany most zaprojektowano jako trojprzeslowy ustroj belkowy o calkowitej dlugości 235,40 m. Najdluzsze jest przeslo środkowe o rozpietości 100,80 m, a przesla skrajne po 66,90 m. Calkowita szerokośc mostu wynosi 16,90 m, w tym ściezka pieszo-rowerowa o szerokości 3,70 m. Wysokośc konstrukcyjna przesel jest zmienna i wynosi 3,16 m w cześci środkowej, a na podporze 4,83 m. Projekt uwzglednia wszelkie ograniczenia wynikające z Decyzji o Środowiskowych Uwarunkowaniach, dlatego zrezygnowano z podpor w nurcie rzeki. Dzieki temu, po uporządkowaniu otoczenia mostu i rzeki, zmiany bedą korzystne takze dla zeglugi. Glownym zalozeniem projektowym nowego mostu jest poprawa podstawowych charakterystyk geometrycznych mostu i dostosowanie nowej konstrukcji do wyzszej klasy obciązen A wg normy PN-85/S-10030. Charakterystyczne parametry techniczne mostu zapewniają zwiekszenie liczby pasow ruchu z dwoch do trzech dla kazdego kierunku. Pomost budowanego mostu jest w konstrukcji stalowej zlozonej z czterech belek dwuteowych polączonych ze sobą poprzecznicami. Na konstrukcji tej bedzie wykonana plyta wspolpracująca z betonu C35/45, polączona z dźwigarami glownymi za pomocą sworzni zgrzewanych.
Foundations of Civil and Environmental Engineering, 2004
A variational formulation of the inequality problem of a plate resting on a foundation is develop... more A variational formulation of the inequality problem of a plate resting on a foundation is developed. The unilateral interaction conditions between the plate and its foundation are taken into account. For the plate the kinematical model of Reissner- Mindlin is applied and the elastoplastic material behaviour is assumed. The foundation is modelled as an elastoplastic medium of Winkler type. These fundamental assumptions impose inequality constraints on some quantities describing the plate-foundation system and, on the mathematical side, lead to an unilateral boundary value problem. We present a unified approach to this problem in which both the conditions of unilateral contact and those of elastoplastic behaviour are governed by variational inequalities. The proposed variational formulation consists of a variational equation and three variational inequali- ties. The finite element solution to the weak formulation is defined and numerical results for some test examples are presented.
The work is concerned with the determination of effective material parameters of reactive powder ... more The work is concerned with the determination of effective material parameters of reactive powder concrete (RPC) in the range of its nonlinear response. We have used a two-scale modelling technique and carried out a series of experimental tests which allow us to validate the proposed numerical model of the considered RPC concrete. The behavior of a RPC concrete on a macro scale is described on the basis of phenomena occurring in the microstructure of material. The material microstructure is taken into account by means of a representative volume element (RVE), the structure of which is generated in a stochastic way with data from the designed recipes of RPC. It is assumed that the microstructure of RPC is composed of isotropic linear elastic—(perfectly) brittle constituents and at the macro scale the material is homogenized. This approach is a good basis for a simple modelling of microcracks that cause the nonlinear behaviour of the material at the macro level. The numerical analysis is carried out here for the plane stress state problem, and at each level of analysis the finite element method is applied.
Modern building materials, structures and techniques, Dec 3, 2019
The aim of the paper is to present a global analysis of a precast, reinforced building structure.... more The aim of the paper is to present a global analysis of a precast, reinforced building structure. At the design stage, information about structural behaviour of particular elements and the whole structure as well as its response to applied loads are obtained. While solving the problem, the load-bearing elements and the type and deformability of connections have to be defined. The latter is especially significant in the case of precast structure models. Calculations according to the analytical method are going to be verified by the finite element method.
Computer Assisted Mechanics and Engineering Sciences, Aug 26, 2019
Erwin Stein passed away on 19th December 2018 at the age of 87, a few days after he had lost cons... more Erwin Stein passed away on 19th December 2018 at the age of 87, a few days after he had lost consciousness when working at his desk. He was a mentor and a dear friend to many of us in the community of computational mechanics. Professor Erwin Stein was a nationally and internationally highly renowned scholar with outstanding achievements and important contributions to the development of computational mechanics. With his passion for scientific research and a positive attitude to life, he was able to gather around him many talented students and to create a leading research centre-the so-called "Stein-School". He supervised 57 PhD theses and 6 habilitation theses. Many of his pupils and co-workers have become full professors at universities in Germany and abroad. He built up a worldwide scientific network of co-workers from many countries, including China, Poland, Russia and Ukraine. In recognition of his significant accomplishments and activities Professor Stein received many prestigious awards and honorary degrees, inter alia, the Gauss-Newton Medal-the highest award given by the International Association for Computational Mechanics (IACM), and the Ritz-Galerkin Medal-the highest distinction awarded by the European Community on Computational Methods in Applied Sciences (ECCOMAS). It should be also emphasized here that Professor Stein contributed a lot to the development of computational mechanics in Poland. He established and maintained effective cooperation with Polish research institutions in the 1980s, mainly with the Institute of Fundamental Technological Research and the Poznan University of Technology. He visited the institutions, gave lectures there, and invited Polish colleagues for research stays at his Institute of Structural Mechanics and Numerical Mechanics in Hannover. In recognition of his great merits and profound contributions to the Polish community of mechanics he was awarded the honorary doctorate degree of PUT (1977) and the O.C. Zienkiewicz Medal by the Polish Association of Computational Mechanics (2009). It can truly be said that he was a friend of Poland. Erwin Stein was born on 5 July 1931 in Altendiez near Diez/Lahn, Germany. He studied civil engineering and mathematics at the Technische Hochschule Darmstadt (1951-1958), which he completed with his diploma in civil engineering (Diplom-Ingenieur mit Mathematik-Tauschfächern). During his studies (1956-1957) he additionally worked part-time on the static analysis and design of engineering structures, which he continued after finishing the studies in 1958 by working for a consulting firm in bridge engineering (design of a composite bridge of steel and prestressed concrete). In 1953 he got married and on 4 November 2018 Erwin and Giesela Stein celebrated their iron wedding anniversary-65 years side by side. They had two daughters and a son.
organized the first conference called "Computer Methods in Mechanics of Structures" (MKMK). This ... more organized the first conference called "Computer Methods in Mechanics of Structures" (MKMK). This gives our conferences a significant position as one of the world's longest-held meetings of researchers dealing with the use of numerical methods in solving engineering problems. The conferences, which have been organized since 1995 by the Polish Society of Computer Methods in Mechanics, have developed with their age and, starting from the initial 29 lectures delivered during the first MKMK, have grown up to 247 papers presented at the 22 nd CMM (CMM2017). CMM2017 was hosted by the Lublin University of Technology, which was also of special significance, as it happened in the year when Lublin celebrated its 700 th anniversary of city rights.
This article is an open access article distributed under the terms and conditions of the Creative... more This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY
International Journal for Multiscale Computational Engineering, 2014
The paper is concerned with the modeling of reactive powder concrete (RPC) by using the method of... more The paper is concerned with the modeling of reactive powder concrete (RPC) by using the method of numerical homogenization. More specifically, a two-scale modeling approach and the finite element method are used. The behavior of a model of RPC on the macro scale is described on the basis of the phenomena occurring in the microstructure of the material. The applied approach makes it possible to take into account the microstructure of material as concerns the different mechanical properties of its constituents. The method does not require any knowledge of the constitutive equations at the macro level, which are determined implicitly by solving a boundary value problem for a representative volume element (RVE) of RPC on the micro level. In order to determine the constitutive equations on the macro scale it is necessary to know the layout of microstructure, the constitutive equations at the micro level, and their parameters. In this contribution the response of each of the concrete constituents (cement matrix, sand, crushed quartz) is assumed to be elastic. The microstructure of RPC concrete is randomly generated. A computer program for the two-scale homogenization of 2D disks has been developed and numerical results for micro and micro-macro test problems are presented. Further studies of the considered problem, including also laboratory experiments, are under way.
This article is an open access article distributed under the terms and conditions of the Creative... more This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY
... 165 Tadeusz Burczynski, Michał Bereta, Arkadiusz Poteralski, Mirosław Szczepanik Bioinspired ... more ... 165 Tadeusz Burczynski, Michał Bereta, Arkadiusz Poteralski, Mirosław Szczepanik Bioinspired Algorithms in Multiscale Optimization..... 183 Wacław Kus, Tadeusz Burczynski Sensor Network Design for SpatioTemporal Prediction of Distributed Parameter Systems ...
This paper aims to evaluate experimentally the potentialities of Hybrid Composite Plates (HCPs) t... more This paper aims to evaluate experimentally the potentialities of Hybrid Composite Plates (HCPs) technique for the shear strengthening and repairing of reinforced concrete (RC) beams. HCP is a thin plate of Strain Hardening Cementitious Composite (SHCC) reinforced with Carbon Fiber Reinforced Polymer (CFRP) laminates. For this purpose, an experimental program composed of four Rectangular and five T-cross section beams was executed to assess the strengthening efficiency of HCPs technique. There were two control beams without any type of shear reinforcement, and seven beams strengthened with HCPs. The HCPs were applied to the lateral faces of the beams by using a combination of epoxy adhesive and mechanical anchors. The bolts were applied with a certain torque in order to increase the concrete confinement. To have a better understanding of the shear behavior of SHCC material, Iosipescu shear tests were carried out, and the results were used to derive their fracture mode II parameters. To further explore the potentialities of the HCPs technique for the shear strengthening, the experimental tests were simulated numerically by a FEM-based computer program considering the material properties obtained experimentally. After demonstration of the good predictive performance of the numerical model, a parametric study was executed to investigate the influence of some parameters on the load carrying capacity of the strengthened beams, namely: i) Use a mortar instead of the SHCC; ii) application of different applied torque level to the mechanical anchors; iii) different bond condition between HCPs and concrete substrate.
The first reason why concrete is a very useful material in construction is because of its density... more The first reason why concrete is a very useful material in construction is because of its density and strength. However, they tend to crack and require constant fixing, and this is usually expensive and tiresome. This research aims to investigate the feasibility of employing sodium alginate, a naturally occurring polysaccharide, as an encapsulated self-healing system for concrete. When sodium alginate is applied on concrete, it interacts with the calcium ions in the concrete to create a calcium alginate gel which helps to close up any cracks and also increases the durability of the concrete. The study embraced the usage of sodium alginate, rapeseed oil, calcium chloride, and water hydrate, which were blended with the IKA T25 harmonisation machine. The outcomes of the experiments indicate that self-healing concrete based on sodium alginate has higher durability, and the need for repairs is minimised; thus, the use of sodium alginate in new construction can be considered a promising direction.
The paper is concerned with a numerical homogenization technique for determination of effective m... more The paper is concerned with a numerical homogenization technique for determination of effective material properties of brick masonry in the elastic range. The homogenization problem is posed in the plane state of stress. The corresponding boundary value problem on a representative cell is discretized by the finite element method. The quadrilateral finite element with four nodes and eight degrees of freedom is applied and our own computer program is developed. The homogenization technique allows one to determine for masonry, which is an inhomogeneous two-phase composite medium, an equivalent homogeneous orthotropic material characterized by five material constants. The homogenized material constants can further be used in an analysis of large-scale masonry structures. The obtained results of numerical simulations are compared with predictions of the value of elastic modulus for masonry by other researches, and qualitative agreement can be observed.
Most Lecha w Poznaniu to nazwa obiektu skladającego sie z dwoch niezaleznych, dopelniających sie ... more Most Lecha w Poznaniu to nazwa obiektu skladającego sie z dwoch niezaleznych, dopelniających sie ale pobudowanych w roznych okresach czasu mostow drogowych ─ polnocnego i poludniowego ─ nad rzeką Wartą w ciągu ulic Lechickiej i Baltyckiej. Polnocny Most Lecha jest obecnie w trakcie gruntownej przebudowy (rys. 1, 2). Praca zawiera najwazniejsze informacje związane z obecną przebudową Mostu Lecha, dotyczące m.in. historii obiektu oraz jego znaczenia w ukladzie komunikacyjnym i rozwiązan konstrukcyjnych. Projekt przebudowy Mostu Lecha obejmuje calkowitą rozbiorke istniejącego od 1953 roku mostu, budowe nowego stalowo-betonowego mostu zespolonego w tej samej lokalizacji oraz dostosowanie dojazdow (rys. 1). Obecnie budowany most zaprojektowano jako trojprzeslowy ustroj belkowy o calkowitej dlugości 235,40 m. Najdluzsze jest przeslo środkowe o rozpietości 100,80 m, a przesla skrajne po 66,90 m. Calkowita szerokośc mostu wynosi 16,90 m, w tym ściezka pieszo-rowerowa o szerokości 3,70 m. Wysokośc konstrukcyjna przesel jest zmienna i wynosi 3,16 m w cześci środkowej, a na podporze 4,83 m. Projekt uwzglednia wszelkie ograniczenia wynikające z Decyzji o Środowiskowych Uwarunkowaniach, dlatego zrezygnowano z podpor w nurcie rzeki. Dzieki temu, po uporządkowaniu otoczenia mostu i rzeki, zmiany bedą korzystne takze dla zeglugi. Glownym zalozeniem projektowym nowego mostu jest poprawa podstawowych charakterystyk geometrycznych mostu i dostosowanie nowej konstrukcji do wyzszej klasy obciązen A wg normy PN-85/S-10030. Charakterystyczne parametry techniczne mostu zapewniają zwiekszenie liczby pasow ruchu z dwoch do trzech dla kazdego kierunku. Pomost budowanego mostu jest w konstrukcji stalowej zlozonej z czterech belek dwuteowych polączonych ze sobą poprzecznicami. Na konstrukcji tej bedzie wykonana plyta wspolpracująca z betonu C35/45, polączona z dźwigarami glownymi za pomocą sworzni zgrzewanych.
Foundations of Civil and Environmental Engineering, 2004
A variational formulation of the inequality problem of a plate resting on a foundation is develop... more A variational formulation of the inequality problem of a plate resting on a foundation is developed. The unilateral interaction conditions between the plate and its foundation are taken into account. For the plate the kinematical model of Reissner- Mindlin is applied and the elastoplastic material behaviour is assumed. The foundation is modelled as an elastoplastic medium of Winkler type. These fundamental assumptions impose inequality constraints on some quantities describing the plate-foundation system and, on the mathematical side, lead to an unilateral boundary value problem. We present a unified approach to this problem in which both the conditions of unilateral contact and those of elastoplastic behaviour are governed by variational inequalities. The proposed variational formulation consists of a variational equation and three variational inequali- ties. The finite element solution to the weak formulation is defined and numerical results for some test examples are presented.
The work is concerned with the determination of effective material parameters of reactive powder ... more The work is concerned with the determination of effective material parameters of reactive powder concrete (RPC) in the range of its nonlinear response. We have used a two-scale modelling technique and carried out a series of experimental tests which allow us to validate the proposed numerical model of the considered RPC concrete. The behavior of a RPC concrete on a macro scale is described on the basis of phenomena occurring in the microstructure of material. The material microstructure is taken into account by means of a representative volume element (RVE), the structure of which is generated in a stochastic way with data from the designed recipes of RPC. It is assumed that the microstructure of RPC is composed of isotropic linear elastic—(perfectly) brittle constituents and at the macro scale the material is homogenized. This approach is a good basis for a simple modelling of microcracks that cause the nonlinear behaviour of the material at the macro level. The numerical analysis is carried out here for the plane stress state problem, and at each level of analysis the finite element method is applied.
Modern building materials, structures and techniques, Dec 3, 2019
The aim of the paper is to present a global analysis of a precast, reinforced building structure.... more The aim of the paper is to present a global analysis of a precast, reinforced building structure. At the design stage, information about structural behaviour of particular elements and the whole structure as well as its response to applied loads are obtained. While solving the problem, the load-bearing elements and the type and deformability of connections have to be defined. The latter is especially significant in the case of precast structure models. Calculations according to the analytical method are going to be verified by the finite element method.
Computer Assisted Mechanics and Engineering Sciences, Aug 26, 2019
Erwin Stein passed away on 19th December 2018 at the age of 87, a few days after he had lost cons... more Erwin Stein passed away on 19th December 2018 at the age of 87, a few days after he had lost consciousness when working at his desk. He was a mentor and a dear friend to many of us in the community of computational mechanics. Professor Erwin Stein was a nationally and internationally highly renowned scholar with outstanding achievements and important contributions to the development of computational mechanics. With his passion for scientific research and a positive attitude to life, he was able to gather around him many talented students and to create a leading research centre-the so-called "Stein-School". He supervised 57 PhD theses and 6 habilitation theses. Many of his pupils and co-workers have become full professors at universities in Germany and abroad. He built up a worldwide scientific network of co-workers from many countries, including China, Poland, Russia and Ukraine. In recognition of his significant accomplishments and activities Professor Stein received many prestigious awards and honorary degrees, inter alia, the Gauss-Newton Medal-the highest award given by the International Association for Computational Mechanics (IACM), and the Ritz-Galerkin Medal-the highest distinction awarded by the European Community on Computational Methods in Applied Sciences (ECCOMAS). It should be also emphasized here that Professor Stein contributed a lot to the development of computational mechanics in Poland. He established and maintained effective cooperation with Polish research institutions in the 1980s, mainly with the Institute of Fundamental Technological Research and the Poznan University of Technology. He visited the institutions, gave lectures there, and invited Polish colleagues for research stays at his Institute of Structural Mechanics and Numerical Mechanics in Hannover. In recognition of his great merits and profound contributions to the Polish community of mechanics he was awarded the honorary doctorate degree of PUT (1977) and the O.C. Zienkiewicz Medal by the Polish Association of Computational Mechanics (2009). It can truly be said that he was a friend of Poland. Erwin Stein was born on 5 July 1931 in Altendiez near Diez/Lahn, Germany. He studied civil engineering and mathematics at the Technische Hochschule Darmstadt (1951-1958), which he completed with his diploma in civil engineering (Diplom-Ingenieur mit Mathematik-Tauschfächern). During his studies (1956-1957) he additionally worked part-time on the static analysis and design of engineering structures, which he continued after finishing the studies in 1958 by working for a consulting firm in bridge engineering (design of a composite bridge of steel and prestressed concrete). In 1953 he got married and on 4 November 2018 Erwin and Giesela Stein celebrated their iron wedding anniversary-65 years side by side. They had two daughters and a son.
organized the first conference called "Computer Methods in Mechanics of Structures" (MKMK). This ... more organized the first conference called "Computer Methods in Mechanics of Structures" (MKMK). This gives our conferences a significant position as one of the world's longest-held meetings of researchers dealing with the use of numerical methods in solving engineering problems. The conferences, which have been organized since 1995 by the Polish Society of Computer Methods in Mechanics, have developed with their age and, starting from the initial 29 lectures delivered during the first MKMK, have grown up to 247 papers presented at the 22 nd CMM (CMM2017). CMM2017 was hosted by the Lublin University of Technology, which was also of special significance, as it happened in the year when Lublin celebrated its 700 th anniversary of city rights.
This article is an open access article distributed under the terms and conditions of the Creative... more This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY
International Journal for Multiscale Computational Engineering, 2014
The paper is concerned with the modeling of reactive powder concrete (RPC) by using the method of... more The paper is concerned with the modeling of reactive powder concrete (RPC) by using the method of numerical homogenization. More specifically, a two-scale modeling approach and the finite element method are used. The behavior of a model of RPC on the macro scale is described on the basis of the phenomena occurring in the microstructure of the material. The applied approach makes it possible to take into account the microstructure of material as concerns the different mechanical properties of its constituents. The method does not require any knowledge of the constitutive equations at the macro level, which are determined implicitly by solving a boundary value problem for a representative volume element (RVE) of RPC on the micro level. In order to determine the constitutive equations on the macro scale it is necessary to know the layout of microstructure, the constitutive equations at the micro level, and their parameters. In this contribution the response of each of the concrete constituents (cement matrix, sand, crushed quartz) is assumed to be elastic. The microstructure of RPC concrete is randomly generated. A computer program for the two-scale homogenization of 2D disks has been developed and numerical results for micro and micro-macro test problems are presented. Further studies of the considered problem, including also laboratory experiments, are under way.
This article is an open access article distributed under the terms and conditions of the Creative... more This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY
... 165 Tadeusz Burczynski, Michał Bereta, Arkadiusz Poteralski, Mirosław Szczepanik Bioinspired ... more ... 165 Tadeusz Burczynski, Michał Bereta, Arkadiusz Poteralski, Mirosław Szczepanik Bioinspired Algorithms in Multiscale Optimization..... 183 Wacław Kus, Tadeusz Burczynski Sensor Network Design for SpatioTemporal Prediction of Distributed Parameter Systems ...
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