Rozprawy doktorskie na temat „Reinforced concrete load bearing walls”

The wall design equations available in major codes of practice (e.g. AS3600 and ACI318) are intended for the design of normal strength concrete load bearing walls supported at top and bottom only. These codes fail to recognise any contribution to load capacity from restraints on the side edges. They also fail to give guidance on the applicability of the equations to high strength concrete. Further, they do not consider slender walls. In many situations walls have side edges restrained and are composed of high strength concrete with high slenderness ratios. The recognition of these factors in the codes would result in thinner walls and consequently savings in construction costs. In this thesis, the focus is on the development of a design formula and new design methods for axially loaded reinforced concrete wall panels. The design of walls having side restraints and being composed of high strength concrete is given particular attention. An experimental program has been undertaken to obtain data for the derivation of applicable formulae and to verify the analytical methods developed herein. Note that, the test results and other data available in published literature have also been used to develop the design formula. The formula encompasses effective length, eccentricity and slenderness ratio factors and is proposed for normal and high strength concrete walls simply supported at top and bottom only (one-way) and simply supported on all four sides (two-way). The major portion of the experimental program focuses on a series of normal and high strength concrete walls simply supported at top and bottom only (one-way), and simply supported on all four sides (two-way) with eccentric axial loading. The behaviour of the test panels is noted, particularly the difference between the normal and high strength concrete panels. A Layer Finite Element Method (LFEM) is used as an analytical tool for walls in two-way action. The LFEM gives comparable results to the test data and the proposed design formula. As part of the research, a program named WASTABT has also been developed to implement a more accurate analytical method involving the instability analysis of two-way action walls. WASTABT is proven to be a useful design tool in situations where the walls have (i) various reinforcement ratio in one or two layers; (ii) composed of normal or high strength concrete; (iii) various eccentricity.

The wall design equations available in major codes of practice (e.g. AS3600 and ACI318) are intended for the design of normal strength concrete load bearing walls supported at top and bottom only. These codes fail to recognise any contribution to load capacity from restraints on the side edges. They also fail to give guidance on the applicability of the equations to high strength concrete. Further, they do not consider slender walls. In many situations walls have side edges restrained and are composed of high strength concrete with high slenderness ratios. The recognition of these factors in the codes would result in thinner walls and consequently savings in construction costs. In this thesis, the focus is on the development of a design formula and new design methods for axially loaded reinforced concrete wall panels. The design of walls having side restraints and being composed of high strength concrete is given particular attention. An experimental program has been undertaken to obtain data for the derivation of applicable formulae and to verify the analytical methods developed herein. Note that, the test results and other data available in published literature have also been used to develop the design formula. The formula encompasses effective length, eccentricity and slenderness ratio factors and is proposed for normal and high strength concrete walls simply supported at top and bottom only (one-way) and simply supported on all four sides (two-way). The major portion of the experimental program focuses on a series of normal and high strength concrete walls simply supported at top and bottom only (one-way), and simply supported on all four sides (two-way) with eccentric axial loading. The behaviour of the test panels is noted, particularly the difference between the normal and high strength concrete panels. A Layer Finite Element Method (LFEM) is used as an analytical tool for walls in two-way action. The LFEM gives comparable results to the test data and the proposed design formula. As part of the research, a program named WASTABT has also been developed to implement a more accurate analytical method involving the instability analysis of two-way action walls. WASTABT is proven to be a useful design tool in situations where the walls have (i) various reinforcement ratio in one or two layers; (ii) composed of normal or high strength concrete; (iii) various eccentricity.
Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
School of Engineering
Full Text

Concrete structures regularly require strengthening due to various reasons. These structures include bridges, buildings and infrastructure, across numerous sectors and industries. Based on the load-carrying capacity of structures and proposed future applications, a vast array of strengthening methods may be utilised. Due to rapid advancements in construction materials, technology has led to the achievement of being able to secure safer, more economical and functional buildings. Of the innovative materials, Fibre Reinforced Polymer (FRP) appears to be an encouraging solution for the retrofitting and strengthening of Reinforced Concrete (RC) structures because of its unique properties. These properties include: high strength-to-weight ratio; high fatigue endurance; environmental degradation and corrosion resistance. FRP is also durable and very flexible for application to the various shapes of structural members. Further, it is easy to install, with a negligible increase in structural size and weight. The application of FRP is dependent upon the type of structural member plus its behaviour. It can be used to enhance the load capacities (axial, flexural, or shear), ductility, rigidity, the remaining fatigue life as well as the durability against harsh environments.
Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
Griffith School of Engineering
Science, Environment, Engineering and Technology
Full Text

The simplified wall design formulae specified in the Australian (AS3600) and American (ACI318) concrete standards are intended for the design of normal strength concrete load bearing walls supported at top and bottom only. These practical codes fail to recognise any contribution to load capacity from restraints on all four sides, and do not provide recommendations and design equations for walls with openings (window and door). Also the current code methods are not applicable to the design of walls with high strength concrete (f’c>65MPa) or high slenderness ratios (H/tw>30). In many practical situations wall panels are restrained on all four sides and have openings. In other cases, high strength concrete walls may have reduced their thickness leading to a high slenderness ratio. The recognition and inclusion of such factors lacking in the current codes would result in more reliable and applicable design methods. A total of forty-seven (47) reinforced concrete wall panels were tested in the laboratory in three stages. Seventeen (17) walls with one and two openings in one-way action were tested in Stage one and eighteen (18) identical walls in two-way action were tested in Stage two. In the first two stages, the test panels had slenderness ratios between 30 and 40 and were of higher concrete strengths from 50MPa to 100MPa, and were subjected to a uniformly distributed axial load with an eccentricity of tw/6. In addition to highlighting the experimental set-up, typical crack patterns, failure modes, load- deflection behaviour and ultimate loads were also reported in some detail. Finally twelve (12) wall panels were tested in Stage three to investigate the behaviour of concrete wall panels with various opening configurations including wide window and door type with asymmetric location. The test panels had a constant slenderness ratio of 30 and a concrete strength of 65MPa. The same eccentric loading was applied and the panels were tested in both one- and two-way action. Utilising these test results, an empirical formula predicting the ultimate load of walls with openings was proposed. A favourable comparison between the predicted results and the test data (including the present and other experimental test results) indicates that the proposed formula is accurate and reliable for use in design. A numerical study was also undertaken to verify the effectiveness of the Layered Finite Element Method (LFEM) in predicting the failure characteristics of reinforced concrete walls with openings. The LFEM was used to model, six (6) normal strength concrete walls tested by Saheb and Desayi and thirty-five (35) concrete wall panels with openings tested in this research. The ultimate loads, load-deflection responses up to failure, deflected shapes and crack patterns predicted by the LFEM were compared favourably to the experimental observations. The comparative study also confirmed that the LEFM is a reliable and effective numerical modelling technique for determining ultimate load capacity of high strength concrete walls with high slenderness ratio and various opening configurations. Upon verification, the LFEM was then used as an effective tool to undertake three parametric studies, on a wide range of opening configurations, slenderness ratios and concrete strengths. The purpose of these parametric studies was threefold: (1) to provide missing data that were not covered by the code methods and existing empirical formulae due to their limited scope; (2) to conduct LFEM simulations which helped to reduce the number of labour intensive and very costly laboratory tests; (3) to validate the performance of the proposed formula in predicting the load carrying capacity of wall panels with openings. In total, 20, 64 and 108 wall models were analysed respectively for three parametric studies. The study confirms the accuracy and reliability of both the LFEM and the proposed formula. To this end, both the LFEM and the proposed formula can be used as an effective tool for the analysis and design of normal and high strength concrete walls with openings and high slenderness ratios performing in both one-and two- way action.
Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
Griffith School of Engineering
Science, Environment, Engineering and Technology
Full Text

Master’s thesis is based on analysis and design of a load bearing structure of an mountains hotel. Mountain hotel schould be realized in the village Vernirovice in Šumperk district. The proposed structure is formed 4th floors. In 1.NP is a restaurant, a sports and wellness center. In 2.NP in the right side is situated the swimming pool. In 2 to 4 floor are located rooms. This structure is supported with a strip footing made of reinforced concrete. The main load-bearing elements in the vertical direction are in 1.NP reinforced concrete walls and columns, the upper floors bearing masonry walls of ceramic blocks THERM. The inner support walls are 300 mm thick, outside support walls are 400 mm thick. Floors are constructed of carrying plates with girders above the larger openings. These plates and girders are made of reinforced concrete. In the 2 floor are beams with the span of 8,8 m. These girders are designed of prestressed concrete cause the large loads. Individual levels are connected with monolithic concrete staircases. Around the middle of the building is a monolithic reinforced concrete elevator shaft. The highest elevation above grade level is 16 m. The thesis also deals with relevant drawing documentations for chosen parts of construction.The building is located in the ski area VI and IV wind areas.

Master´s thesis is based on analysis and design of a load-bearing structure of multifunctional house. The main load-bearing elements in the vertical direction are the monolithic reinforced walls and the main load-bearing elements in the horizontal direction are monolithic reinforced concrete plates. The connection of individual floors is made of monolithic reinforced concrete staircases. The foundation of the building is realized through a system of strips foundation. Design drawings are made to selected elements of the structure.

Master’s thesis is based on analysis and design of a load bearing structure of an apartment block. This structure is supported with a strip footing made of reinforced concrete. The above-ground part of designed structure consists of brick masonry. Floors are constructed of carrying plates. These plates are made of reinforced concrete and precast boards (prestressed concrete). Individual levels are connected with monolithic concrete staircases. The thesis also deals with relevant drawing documentations for chosen parts of construction.

This diploma thesis is focused on design cast-in-place reinforced concrete structure multi-storey multifunctional building according to the source material. Specifically, foundation slab and external wall in B1 taking into account the waterproofness of the construction. Then staircase, column in lowest storey and two floor slab are designed as selected load-bearing structure. Elements are dimensioned according to ČSN EN 1992-1-1: Design of concrete structures - general rules and rules for building structures. In the drawing part of the diploma thesis are drawn drawings of the shapes and reinforcement.

The master's thesis deals with static analysis of selected reinforced concrete elements of an apartment building. Specifically solved are the reinforced concrete slab of above-ground floor, point-supported slab of underground garage, the most exposed column, staircase, load-bearing wall of shear core, external load-bearing wall and building foundation on piles. Load effects were calculated using the Axis VM 12 software. Design of foundation was solved in the Geo 5 software. The thesis includes shape drawing documentation of selected elements.

The diploma thesis deals with the technological stage of the lower structure, namely laying on piled foundations, including laying of a building pit with pilot reinforced concrete walls, and a rough top structure made of reinforced concrete walls, cores and reinforced concrete ceiling structure. The content is a technical report, solutions of wider transport relations, time and financial planning, studies of the main technological stages, equipment of the construction site of solved stages, design of the main building machines and mechanisms, technological regulations, control and test plans, safety and health protection at work, , thermal engineering assessment of selected constructions, budget, staff deployment balance, work progress scheme.

Unreinforced masonry walls subjected to blast loading are vulnerable to collapse and fragmentation. The objective of this thesis is to conduct experimental and analytical research for developing a blast retrofit methodology that utilizes polyurea. A total of four unreinforced masonry walls were constructed and tested under various shock tube induced blast pressures at the University of Ottawa Shock Tube Testing Facility. Two of the retrofitted walls had surface-sprayed polyurea. The results indicate that the use of polyurea effectively controlled fragmentation while significantly increased the load capacity and stiffness of masonry walls. Polyurea proved to be an excellent retrofit material for dissipating blast induced energy by providing ductility to the system and changing the failure mode from brittle to ductile. Single degree of freedom (SDOF) dynamic analyses were conducted as part of the analytical investigation. The results show that the analytical model provides reasonably accurate predictions of the specimen response.

Cast in situ or precast reinforced concrete (RC) walls are commonly used in multistorey buildings to withstand gravitational and lateral loadings. Walls restrained along the top and bottom edges by floors, with free vertical edges, subjected to in-plane axial loads behave in one-way action (OW). Axially-loaded walls can also behave in two-way action with lateral support on three sides (TW3S) or four sides (TW4S), formed by floors and intersecting walls, when they are combined to form an isolated box, a bundled box, a coupled core, or a geometric, U-, T- or L-shape. In many circumstances, walls are pierced with openings because of architectural requirements or functional modifications of the structures. However, these openings are a source of weakness and can size-dependently reduce the stiffness and load-bearing capacity of the structure. RC walls subjected to eccentric axial loads can be designed using simplified design methods, provided in major codes of practice, which include, inter alia, the Eurocode 2, the Australian Concrete Standard and the American Concrete Institute Code. However, these code methods do not take into consideration the design of high slenderness wall panels. There is also little guidance in the design codes for walls with openings. With the current advancement in construction materials and technologies, significant cost savings and increases in the net leasable space of a building may be achievable through the design and use of thinner walls. It is thus becoming increasingly important to carry out less conservative and more relevant designs for structural wall elements. Although numerous studies have been undertaken on OW and TW4S walls with and without openings in an effort to better understand the structural behaviour of such walls and further improve their design models, studies on TW3S walls have not been conducted to the same depth. There is a lack of fully comprehensive research on the behaviour of axially-loaded TW3S walls with and without openings, design models for high slenderness TW3S walls with various aspect ratios and design models for TW3S walls with openings. Consequently, there is a need for further studies on TW3S walls with and without openings, which is the focus of this thesis. Given little prior information in the literature on the behaviour of TW3S walls, comprehensive experimental and numerical studies were conducted in this research. A total of 18 wall panels, consisting of 10 solid panels and eight panels with an opening, subjected to a uniformly-distributed axial load at an eccentricity of one-sixth of the wall thickness, were constructed and tested at Griffith University, Gold Coast campus. The influences of several key parameters on the axial load capacity of TW3S wall panels were examined. These parameters included slenderness ratio, aspect ratio and the configuration and position of the openings. The axial load behaviour of the test specimens was studied with regard to cracking characteristics, load-deflection responses and ultimate strengths. Numerical investigations were undertaken by means of a computer program, WASTABT, and commercial finite element software ABAQUS. Specifically, WASTABT was written in the MATLAB programming package to execute an instability analysis for TW3S solid walls (proposed in this research), and the all-encompassing program ABAQUS was used to perform numerical analysis of both TW3S solid walls and TW3S walls with openings. Having established that these numerical programs satisfactorily predicted the experimental outcomes, extensive parametric studies were then carried out to investigate the effects of key parameters on the axial load capacity of full-scale TW3S walls. Particular emphasis was given to the effects of varying the slenderness ratio, aspect ratio, concrete strength, load eccentricity and reinforcement ratio, in addition to the configuration and position of the openings. A number of quantitative conclusions were drawn from the studies, which both enhanced the fundamental understanding of, and provided insight into, the behaviour of axiallyloaded TW3S walls with and without openings. In view of the shortcomings of the code design equations and the scarcity of other available models to estimate the ultimate strength of TW3S walls with and without openings, a set of design models, covering a broader spectrum of designs, was developed in this research. The research focused on the development of simplified design equations, and a rigid-plastic method for TW3S walls with and without openings, along with a hybrid-system method for solely TW3S walls with openings. Comparisons with the test data of the current and previous studies, in addition to the numerical results of WASTABT and ABAQUS, confirmed that the proposed models are satisfactory and reliable, and thus, can serve as useful design aids for engineering applications.
Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
School of Eng & Built Env
Science, Environment, Engineering and Technology
Full Text

Thesis (M.S.)--University of Missouri-Columbia, 2006.
The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file (viewed on April 17, 2009) Includes bibliographical references.

Common construction practice before modern seismic design codes appeared allowed designing columns lap splices located above the slab in each floor or above the foundation. The lack of lap splices and the shear reinforcement was in the form of stirrups with 90-degree bends and spaced at half the depth of the frame member. As a result, the section at the base of these columns is unconfined and susceptible to shear failure or to a premature failure of the lap splices before yielding of the longitudinal bars. The masonry infill walls used as partitions were often ignored by design engineers since such walls were considered as nonstructural architectural elements. However, lessons learned from past earthquakes and from several tests performed have shown that those walls tend to interact with the bounding frame when the structural system is subjected to moderate or severe earthquake ground motions. The first part of an experimental testing program carried out at the University of British Columbia (UBC) in Vancouver, Canada tested the performance of 1/2 scale Gravity Load Designed Reinforced Concrete (GLDRC) frames with unreinforced masonry walls. This testing program consisted of one monotonic loading test on an infilled frame and two series of shake table tests, one on an infilled frame and one on a bare frame with the UBC Earthquake Engineering Research Facility (EERF) unidirectional shake table. It was concluded from these tests that the interaction with the unreinforced masonry wall stiffens the frame, reduces the deformations, and allows dissipating energy through nonlinear response for several cycles of deformation. It was determined that the governing failure mode for the masonry wall was shear sliding for monotonic and dynamic loading. There was consistent evidence of local lateral deformations at the base of the gravity load designed columns due to construction cold joints and inadequate lap splices that may result in shear failure of the base of the column due to the interaction with the masonry infill during a severe earthquake.

Concrete block masonry is a common building material used worldwide, including Canada. Reinforced masonry buildings, designed according to the requirements of recent building codes, may result in seismically safe structures. However, unreinforced masonry (URM) buildings designed and constructed prior to the development of modern seismic design codes are extremely vulnerable to seismic induced damage. Replacement of older seismically deficient buildings with new and seismically designed structures is economically not feasible in most cases. Therefore, seismic retrofitting of deficient buildings remains to be a viable seismic risk mitigation strategy. Masonry load bearing walls are the most important elements of such buildings, potentially serving as lateral force resisting systems. A seismic retrofit research program is currently underway at the University of Ottawa, consisting of experimental and analytical components for developing new seismic retrofit systems for unreinforced masonry walls. The research project presented in this thesis forms part of the same overall research program. The experimental component includes design, construction, retrofit and testing of large-scale load bearing masonry walls. Two approaches were developed as retrofit methodologies, both involving reinforcing the walls for strength and deformability. The first approach involves the use of ordinary deformed steel reinforcement as internally added reinforcement to attain reinforced masonry behaviour. The second approach involves the use of internally placed post-tensioning tendons to attain prestressed masonry behaviour. The analytical component of research consists of constructing a Finite Element computer model for nonlinear analysis of walls and conducting a parametric study to assess the significance of retrofit design parameters. The results have led to the development of a conceptual retrofit design framework for the new techniques developed, while utilizing the seismic provisions of the National Building Code of Canada and the relevant CSA material standards.

An improved equation is presented for the prediction of the ultimate strength of the local zone in Load Transfer Tests. The derivation of this new formulation is the result of the investigation of the ultimate bearing strength of plain and reinforced concrete blocks, concentrically loaded. A total of 199 bearing tests were performed on plain and reinforced concrete prisms to evaluate the variables involved in the bearing problem. A finite element analysis of a typical square block loaded with different bearing areas was performed. Two equations, one for plain concrete and the other for reinforced concrete were derived using the Mohr failure criterion. The performance of the derived equations was evaluated against actual test data. The results of this evaluation showed very good agreement between the predicted ultimate strength and the actual test strength for both plain and reinforced concrete. For plain concrete specimens the ratio Ptest/Ppred was 1.05 with a coefficient of variation of 9 percent. In the case of reinforced concrete blocks the ratio Ptest/Ppred was 1.00 with a coefficient of variation of 14 percent.
Master of Science

The matter of this thesis is static design and examination of prestressed storage tank to 50000 tons of sugar. Computational model of the steel roof structure is processed and its effect on the silos. Loads is provided of sugar. Optimal design is performed and assessment ultimate and serviceability limit state reinforced concrete and prestressing horizontal silo wall including local load. Next, it is performed the design of a reinforced concrete of the plane bed and column and assessment at the ultimate limit state. The thesis is also drawing documentation, technical report and visualization of construction process. The aim of this work is to the design of the main components based on the required storage capacity tank, mechanical properties of the stored material and technical amenities.

The diploma thesis is aimed for design and assessment main load bearing elements of a apart-ment building on the ultimate and serviceability limit state. Assessed parts of construction are reinforced concrete slab over the second floor, column and shear wall in the first floor, stairway slab and foundation pad. The elements are assessed in a structural design report according valid standard. There is created drawings. Internal forces are calculated using software Scia Engineer, where is modeled and loaded the construction.

Atualmente, muitas empresas de construção civil não acompanham o avanço tecnológico, preferindo utilizar sistemas convencionais em vez de investir em novas soluções. Além disso, há sérios problemas com mão de obra, que estão cada vez mais presentes na sociedade. Este trabalho apresenta o projeto de um edifício com elementos pré-moldados de Concreto Leve com pérolas de EPS, considerando lajes prontas maciças e paredes portantes, executadas com esse tipo de material. A princípio, foram considerados os estados limites últimos e de serviço para os elementos da estrutura, utilizando os modelos clássicos de análise estrutural. Para modelagem do edifício, foi utilizado o programa comercial SAP2000. Quanto aos procedimentos para dimensionamento das peças, foram preparadas planilhas do Excel, enquanto o detalhamento foi realizado por meio do AutoCAD. Definido o projeto estrutural, foram considerados aspectos construtivos na fábrica e na obra, levando em conta os custos de produção e de transporte, além de apresentar as vantagens que esse sistema construtivo pode proporcionar. Esses custos foram considerados para as lajes prontas maciças e para as paredes pré-moldadas. Mesmo levando em conta apenas os custos de produção e de transporte, o Concreto Leve com EPS foi comparado com o Concreto Autoadensável, o que permitiu visualizar as vantagens do primeiro, quando for considerado o custo global do empreendimento.
Currently, many construction companies do not follow the technological advances, preferring to use conventional systems rather than investing in new solutions. Moreover, there are serious problems with manpower, which are increasingly present in society. This work presents the design of a building with precast elements of lightweight concrete with EPS beads, considering solid slabs ready to use and load bearing walls, made with this type of material. As a rule, the ultimate limit states and serviceability were considered for the elements of the structure, using classical models of structural analysis. For modelling the building, the commercial software SAP2000 was used. Regarding the procedures for dimensioning of the pieces, Excel spreadsheets were prepared, while the detailing was carried out by means of the AutoCAD. Defined structural design, construction aspects were considered in the factory and in the work, taking into account costs of production and transportation, besides presenting the advantages that this constructive system can provide. These costs were considered for the solid slabs ready to use and for the precast walls. Even taking into account only the cost of production and transportation, the Lightweight Concrete with EPS was compared with Self-compacting Concrete, allowing visualize the advantages of the former when considering the overall cost of the project.

The matter of this diploma thesis is a static storage tank for petroleum substances, the study of a solution for appropriate shape of shell and its effort to dihedral for roofing, and the study of effect of the storage of inner roofs walls of the tank to the size of the internal forces. The internal walls are carried out by the method of finite elements in the engineering program Scia Engineering 2013 and on the basis of it, designing of the framing sections of the tank. There is a calculation part of the lower horizontal bias wreaths of the shell and internal supporting wall. All the components are assessed on the 1st limit state of the load-bearing capacity and the 2nd limit state of the application (emergence cracks, limiting voltage in the concrete and a prestressing steel). The existing external wall is assessed only on the marginal status load of carrying capacity. The part of diploma thesis is also drawing documentation, accompanying report and technical report. The goal of the diploma thesis was to design the tank without an occurrence of the cracks in the concrete so as the vertical wall was prestressing only in the horizontal direction and the optimal proposal roof tanks as an addition.

The thesis deals with design and assessment of all supporting parts of cast-in-place reinforced concrete tank. The thesis includes a technical report, static analysis, drawing documentations, construction proces and visualization. The drawing documentation consists of shape and reinforcement drawings of supporting parts.

The theme of the dissertation is structural survey of designed sewage clarification plant. The work deal about designed of reinforcement of the sewage clarification plant. The diameter of the reservoir is 17,8 m and the depth is 6,2 m.

Für die Anwendung des Verbundwerkstoffes „Textilbewehrter Beton“ sind die numerischen und experimentellen Grundlagenerkenntnisse zum Tragverhalten von Bauteilen in für die Baupraxis geeignete Nachweismodelle und Konstruktionsregeln zu überführen. Die aus dem Stahlbetonbau bekannten Ansätze müssen wegen der abweichenden Material- und Verbundeigenschaften für textilbewehrte Betonbauteile angepasst werden. Im Beitrag werden die grundlegenden Tragmechanismen textilbewehrter Elemente unter Zug-, Biege- und Querkraftbeanspruchung sowie punktförmiger Zugbeanspruchung beschrieben und die aus den Untersuchungsergebnissen abgeleiteten Nachweismodelle vorgestellt. Darauf aufbauend werden Sicherheitsbeiwerte für die textile Bewehrung ermittelt und die Berechnungsmodelle in ein Sicherheitskonzept eingebunden. Als einheitlicher Teilsicherheitsbeiwert für Textilbeton wird γtex = 1,5 vorgeschlagen
For the application of the composite material Textile Reinforced Concrete (TRC) the numerical and experimental knowledge of the load bearing behaviour of construction elements has to be transferred into design models and construction rules applicable for the practice. Due to differences in the material and bond properties the design approach known for steel reinforced concrete has to be adjusted for textile reinforced concrete construction parts. In this paper the basic load-bearing mechanisms of textile reinforced concrete under tension, bending and shear loading as well as under concentrated tensile loading are described and empirically derived design models are presented. Based on the experimental results safety factors for the textile reinforcements are determined and the design models are integrated into an overall safety concept. A partial safety factor for textile reinforced concrete of γtex = 1,5 is recommended

Sandwichkonstruktionen mit Deckschichten aus dünnen Metallblechen und Stahlbeton stellen seit Jahrzehnten bewährte und wirtschaftliche Verbundkonstruktionen für Gebäudehüllen dar. Der Einsatz von dünnen Deckschichten aus textilbewehrtem Beton verbindet deren Vorteile und ermöglicht auch bei steigenden Anforderungen an den Wärmeschutz geringe Konstruktionsdicken. Der Beitrag berichtet über die Entwicklung von Ingenieurmodellen zur wirklichkeitsnahen Beschreibung des Tragverhaltens von Sandwichquerschnitten aus textilbewehrtem Beton, Hartschaumdämmkern und geeigneten Verbundmitteln
Sandwich constructions made of thin metal sheets and structural concrete have been reliable and economic composite structures in the past decades. The application of thin-walled facings made of Textile Reinforced Concrete (TRC) combines the advantages of this construction and allows for slender construction thicknesses despite the progressing demands on thermal insulation. This contribution reports on the development of models, which enable the realistic mechanical description of the load-bearing behavior of the sandwich panels made of two TRC-facings and a core of polymeric rigid foam together with suitable connecting devices

Baigiamajame magistro darbe nagrinėjami galimi prekybos ir pramogų centro perdangos ir ledo arenos denginio pagrindinių laikančiųjų konstrukcijų variantai, įvertinami jų techniniai– ekonominiai rodikliai, parenkamas racionalus konstrukcijų variantas tolesniam pastato projektavimui. Nagrinėjamas gelžbetoninės ledo arenos denginio arkos patikimumas, išskiriami rodikliai, darantys didžiausią įtaką konstrukcijos patikimumui, atliekama konstrukcijos parametrinė analizė. Pateikiamos baigiamojo darbo išvados. Projektuojama briaunotoji TT tipo denginio plokštė, gelžbetoninė dviejų lankstų denginio arka su iš anksto įtempta styga, kolona ir polinis pamatas, parengiami šių konstrukcijų darbo brėžiniai. Darbą sudaro 11 dalių: įvadas, aiškinamasis raštas, techninė-ekonominė, konstrukcijų projektavimo ir patikimumo analizės dalys, išvados, literatūros sąrašas. Darbo apimtis – 149 p. teksto be priedų, 43 iliustr., 27 lent., 34 bibliografiniai šaltiniai, 9 A1 lapai brėžinių. Atskirai pridedami darbo priedai.
This MA thesis focuses on the possible versions of floors in a Shopping and Entertainment Centre as well as the roof load-bearing constructions of an Ice Arena. Their technical and economic parameters are evaluated and a rational construction option for the further building design is selected. This thesis analyses the reliability of the reinforced concrete arch in the Ice Arena, and the parameters that have the biggest influence on the reliability of the construction are singled out. The parameter analysis of the construction is presented. The thesis ends with concluding remarks. The design features a double tee-type roof slab, a reinforced concrete two-hinged arch with a pre-stressed tie, a column and a pile foundation. The working drawings of the above-mentioned constructions are drafted. The thesis consists of 11 parts: the introduction, the expository letter, the technological-economic part, the parts dealing with the construction design and reliability analysis, the conclusions, the bibliography, etc. The scope of the thesis is as follows: 149 pages of text without annexes, 43 figures, 27 tables, 34 bibliographical sources and 9 A1-size pages of drawings. There are annexes attached to the thesis.

This master thesis deals with a draft of precast concrete frame structure on the case of gymnasium building. The major part of this work are transversal and longitudinal frames, consisted of footings, columns, girders and precast floor slab. Other parts of the building are not solved. Thesis consists both static calculations and drawings.

The Master´s thesis subject is a design and an estimation of the load-bearing structure of a multi-storeyed building. The structure has a miscellaneous ground-plan shape consisting of three rectangular tracts and it is placed in the building basement under the ground level. The load-bearing structure involves walls and a floor slab which rises up vertically closer to the ground level in the central tract. Among further components being solved belong stairs, basement slab and beam. The load-bearing structure is solved monolithically as steel concrete component.

Within the frame of my master's thesis I processed a project documentation for a construction of an apartment house in Brno – Židenice. The building is unattached and has 7 floors. On the ground floor there are four individual garages, cellar cubicles and a utility room. There are apartments on all other floors. On the highest floor, there is situated a singular apartment with outdoor terrace and vegetation area. The building is founded on strips made of reinforced concrete, vertical load-bearing structure is made of cermic blocks, floor structure is made of hollow core slabs and staircase is also made of prefabricated elements. The house is insulated with contact thermal insulation made of mineral wool. During the process of creating the projet, I followed all the requirements of actual regulations and legal enactments, to provide sufficient mechanical endurance and stability, health safety of the inner space as well as safety of the natural environment.

Das Trag- und Verbundverhalten textiler Bewehrungen wurde in den vergangen Jahren umfassend experimentell untersucht. Die dabei gewonnenen Erkenntnisse stützen sich jedoch fast ausschließlich auf einaxiale Beanspruchungszustände. Grundsätzlich können aus dem Vergleich von Versuchen an Rovings und an textilen Bewehrungsstrukturen Rückschlüsse auf den Einfluss der Quer- und Stützfäden und der verschiedenen Bindungstechniken auf das einaxiale Tragverhalten von Textilbeton getroffen werden. Offen bleibt jedoch, inwieweit sich die gefundenen Gesetzmäßigkeiten auf mehraxiale Beanspruchungssituationen übertragen lassen. Dadurch werden Fragen bezüglich des Tragverhaltens textiler Bewehrungen unter mehraxialen Zugbeanspruchungen aufgeworfen, welche die Motivation für die vorliegende Arbeit liefern. Die hierzu durchgeführten experimentellen Untersuchungen umfassen 84 Einzelversuche und wurden in einem speziell für zweiaxiale Zugbeanspruchungen entwickelten Versuchsaufbau durchgeführt. Als textile Bewehrungen kamen zwei verschiedene Gelegearten aus AR-Glas und Carbon zum Einsatz. Die Ergebnisse konnten die bisher ausschließlich an einaxialen Dehnkörpern gewonnenen Erkenntnisse über das Tragverhalten textiler Bewehrungen grundsätzlich bestätigen. Für den Übergang von Zustand I zum Zustand II konnte eine Abhängigkeit der Erstrissspannung vom Spannungsverhältnis nachgewiesen werden. Die Merkmale der Zustände IIa und IIb zeigen hingegen keine signifikante Abhängigkeit vom Verhältnis aus Längs- und Querzugspannung. Darüber hinaus haben offenbar durch Querzug induzierte bewehrungsparallele Risse keine maßgeblichen Auswirkungen auf das Verbundverhalten der Rovings in Längsrichtung. Eine wesentliche Erkenntnis aus den biaxialen Zugversuchen mit Carbon betrifft den Einfluss der Welligkeit. Es wurde deutlich, dass der Abbau der Welligkeit in beschichteten textilen Bewehrungen hochgradig lastabhängig ist. In zahlreichen Versuchen mit Carbon kam es innerhalb des Zustands IIb zu Delamination, einem bisher in diesem Umfang nicht beobachteten Effekt. Die Erkenntnisse hinsichtlich des Abbaus der Welligkeit wurden im Anschluss auf das Tragverhalten von AR-Glas übertragen und führten zu einer Neubewertung des bei AR-Glas beobachteten Steifigkeitsdefizits im Zustand IIb. Weiterhin wurde der Einfluss der Orientierung der Bewehrung unter einaxialer Beanspruchung an scheibenartigen Probekörpern untersucht. Es zeigte sich, dass die untersuchten Bewehrungen aus AR-Glas hinsichtlich der Tragfähigkeit bei schiefwinkliger Beanspruchung deutlich unempfindlicher reagieren als Bewehrungen aus Carbon. Für die Reduktion der effektiven Faserbruchspannungen wurde ein mathematisches Modell vorgestellt, welches eine getrennte Beschreibung der geometrischen Einflüsse sowie alle sonstigen, die Faserbruchspannung reduzierenden Effekte erlaubt
The load bearing and bond behaviour of textile reinforcements has been comprehensively studied experimental in recent years. The findings are based almost exclusively on uniaxial loading. Generally, from the comparison of tests on rovings and fabrics conclusions can be drawn about the influence of transverse and supporting threads and different binding patterns on the uniaxial load-bearing behaviour. However, it remains open, to what extend the found principles are applicable to multi-axial loading situations. This raises questions about the load bearing behaviour under multi-axial tension loading, which provide motivation for this work. For the experimental studies on 84 specimens a specially developed test setup for biaxial tensile loading was used. Two different types of textile reinforcements made from AR-glass and carbon fibres were examined. The results generally approve the findings on the structural behaviour of textile reinforcements exclusively derived from uniaxial tests. A relationship between first cracking stress level and biaxial stress ratio has been found. The characteristics of the cracking phases and during stabilized cracking, however, show no significant dependencies on the ratio of longitudinal and transverse tensile stresses. Furthermore, parallel cracks induced by transverse tensile stresses have no significant impact on the bond behaviour of longitudinal rovings. An essential result from biaxial tensile tests with carbon is the strong influence of waviness. It became clear that the reduction of waviness in coated textile reinforcement is highly load-dependent. In numerous experiments with carbon reinforcement delamination occurred during stabilized cracking – an effect, that has been observed in this large scale for the first time. The findings regarding the reduction of the waviness were subsequently applied to AR-glass and led to a revaluation of the known stiffness deficit in the phase IIb. Furthermore, the influence of reinforcement orientation has been studied on discoidal specimens under uni-axial loading. It was found that the load bearing capacity of carbon reinforcement is much more sensible to load orientation than AR-glass. A mathematical model was presented, which allows the separate description of geometric factors and as well as all other effects that reduce the fibre tensile strength

Master's thesis is focused on the design and assessment of load-bearing structure of the family house. Model reinforced concrete structure is created in RFEM. Elements of reinforced concrete are Assessed in accordance with EN 1992-1-1. Excepting static calculation is part of documentation the technical report and drawings shape and reinforcement.

Im Rahmen der vorliegenden Arbeit wird das Versuchskonzept für zweiaxiale Zug-Zug-Versuche an textilbewehrten Betonscheiben behandelt. Diese Arbeit soll einen Beitrag leisten, die Kenntnisse aus dem Maschinenbau, der Mechanik in den Bereich der Bauingenieure und Baustoffe umzusetzen, um alle Effekte, die vom Versuchstand verursacht werden, öffentlich zu machen. Es ist ein Versuchskonzept zu erarbeiten, wie ein experimenteller Zug-Zug-Versuch optimal zu gestalten ist, um das Tragverhalten des textilbewehrten Betons genau zu ermitteln. Die Arbeit ist hauptsächlich in zwei Teile gegliedert. Der erster Teil befasst sich mit dem Thema „Versuchsvorbereitung“. Es beinhaltet folgende Hauptpunkte: • Der erste Punkt beschäftigt sich mit der Auswertung durchgeführter Versuche und deren Versuchsaufbauten. Hier werden Aspekte von der konstruktiven Auslegung der Rahmen bis zur Steuerung der Prüfmaschine behandelt. Es wird diskutiert, welche Effekte auf das Versuchsergebnis vom gewählten Hydrauliksystem bzw. von den Hydraulikzylinder und der Steuerung des Öldrucks ausgehen können. • Im zweiten Punkt wird eine Finite–Element–Simulationen durchgeführt, um die zweiaxialen Zug-Zug-Versuchskörper zu konzipieren. Mit Hilfe von einem Finite–Element– Programm, hier ATENA, wird die Probengeometrie mit den Randbedingungen des Versuchs nachgebildet und optimiert. • Der dritte Punkt beschäftigt sich mit dem Thema „Lasteinleitung“. Ein Konzept für die Verbindung und Kraftübertragung von Stahlplatten (Stahllasche) zur Lasteinleitung in „Beton“ soll entwickelt werden. • Der vierte Punkt beschreibt die gewählte Messmethode der Versuchsdurchführung, und wertet deren Potenzial und Möglichkeiten . Der zweiter Teil der vorliegenden Arbeit beschreibt detailliert die fünf durchgeführten zweiaxialen Zug–Zug–Versuche an mit AR-Glas textilbewehrten Betonscheiben. Die textilbewehrten Betonscheiben werden am Rahmen der zweiaxialen Prüfmaschine eingehängt und zweiaxial mit jeweils konstantem Verhältnis der Beanspruchung in Zug–Zug Richtung belastet, um den Versuchstand zu erproben und auszutesten. Die Gedanken, Ergänzungen und Erkenntnisse der Autorin im Zusammenhang mit dem textilbewehrten Beton und die hier auftretenden Effekte werden auch in diesem Kapitel behandelt. Das Schlusskapitel der Arbeit beinhaltet die Zusammenfassung und den weiteren Ausblick. Aus diesem Anlass werden die wissenschaftlichen Erkenntnisse der vorliegenden Arbeit zusammengefasst
This doctoral thesis pertains to the conception for Bi–axial Tension–Tension Tests of thin textile reinforced concrete plates. This dissertation contributes to the application of mechanical engineering knowledge into the specific area of Material–Construction Engineering; all results obtained from experimental conditions will be released to the public. The conception of this testing regime is presented, as well as the manner in which an experimental Tension–Tension Test can optimally ascertain and accurately predict and describe load-bearing behaviour of textile reinforced concrete (TRC). This thesis is generally subdivided into two parts –“Test Preparation” and the detail of Bi-axial Tension-Tension testing on AR-Glass TRC plates. The “Test Preparation” component of this document includes the following four principal points. The first point is concerned with the assembly of testing equipment. Problems stemming from framework or lack of control over the testing machine are examined here. Negative effects on test results induced by the Hydraulic cylinder and related oil pressure are investigated and complemented in this section. The second point focuses on the numerical simulation used in order to determine the Bi–axial Tension–Tension Test samples. The specimen geometry given the testing boundary conditions was copied and optimized by means of a Finite–Element–Program (ATENA). The third point is concerned with the notion of “load application”. It was necessary to develop a premise for the loading transmission and connection between steel plates (steel mounting plates) and concrete cogs. The final point takes into account the methods used for measuring the Bi–axial Tension–Tension–test of this work. The second component present in this thesis describes in detail the five Bi–axial Tension–Tension–Tests conducted on AR–Glass TRC plates utilized to prove and ensure the accuracy of the experimental equipment. The TRC plate was built on frame of the bi-axial testing machine and received tensile loading in both directions. This loading relationship was held constant in both directions during the test. Furthermore, the author presents her own thoughts, as well as supplemental commentary, associated with textile reinforced concrete and the resulting experimental outcomes. The last chapter closes this doctoral thesis and includes the abstract of and further prospects for this study. All scientific cognitions are summarised in this chapter

Im Rahmen der vorliegenden Arbeit wird das Versuchskonzept für zweiaxiale Zug-Zug-Versuche an textilbewehrten Betonscheiben behandelt. Diese Arbeit soll einen Beitrag leisten, die Kenntnisse aus dem Maschinenbau, der Mechanik in den Bereich der Bauingenieure und Baustoffe umzusetzen, um alle Effekte, die vom Versuchstand verursacht werden, öffentlich zu machen. Es ist ein Versuchskonzept zu erarbeiten, wie ein experimenteller Zug-Zug-Versuch optimal zu gestalten ist, um das Tragverhalten des textilbewehrten Betons genau zu ermitteln. Die Arbeit ist hauptsächlich in zwei Teile gegliedert. Der erster Teil befasst sich mit dem Thema „Versuchsvorbereitung“. Es beinhaltet folgende Hauptpunkte: • Der erste Punkt beschäftigt sich mit der Auswertung durchgeführter Versuche und deren Versuchsaufbauten. Hier werden Aspekte von der konstruktiven Auslegung der Rahmen bis zur Steuerung der Prüfmaschine behandelt. Es wird diskutiert, welche Effekte auf das Versuchsergebnis vom gewählten Hydrauliksystem bzw. von den Hydraulikzylinder und der Steuerung des Öldrucks ausgehen können. • Im zweiten Punkt wird eine Finite–Element–Simulationen durchgeführt, um die zweiaxialen Zug-Zug-Versuchskörper zu konzipieren. Mit Hilfe von einem Finite–Element– Programm, hier ATENA, wird die Probengeometrie mit den Randbedingungen des Versuchs nachgebildet und optimiert. • Der dritte Punkt beschäftigt sich mit dem Thema „Lasteinleitung“. Ein Konzept für die Verbindung und Kraftübertragung von Stahlplatten (Stahllasche) zur Lasteinleitung in „Beton“ soll entwickelt werden. • Der vierte Punkt beschreibt die gewählte Messmethode der Versuchsdurchführung, und wertet deren Potenzial und Möglichkeiten . Der zweiter Teil der vorliegenden Arbeit beschreibt detailliert die fünf durchgeführten zweiaxialen Zug–Zug–Versuche an mit AR-Glas textilbewehrten Betonscheiben. Die textilbewehrten Betonscheiben werden am Rahmen der zweiaxialen Prüfmaschine eingehängt und zweiaxial mit jeweils konstantem Verhältnis der Beanspruchung in Zug–Zug Richtung belastet, um den Versuchstand zu erproben und auszutesten. Die Gedanken, Ergänzungen und Erkenntnisse der Autorin im Zusammenhang mit dem textilbewehrten Beton und die hier auftretenden Effekte werden auch in diesem Kapitel behandelt. Das Schlusskapitel der Arbeit beinhaltet die Zusammenfassung und den weiteren Ausblick. Aus diesem Anlass werden die wissenschaftlichen Erkenntnisse der vorliegenden Arbeit zusammengefasst.
This doctoral thesis pertains to the conception for Bi–axial Tension–Tension Tests of thin textile reinforced concrete plates. This dissertation contributes to the application of mechanical engineering knowledge into the specific area of Material–Construction Engineering; all results obtained from experimental conditions will be released to the public. The conception of this testing regime is presented, as well as the manner in which an experimental Tension–Tension Test can optimally ascertain and accurately predict and describe load-bearing behaviour of textile reinforced concrete (TRC). This thesis is generally subdivided into two parts –“Test Preparation” and the detail of Bi-axial Tension-Tension testing on AR-Glass TRC plates. The “Test Preparation” component of this document includes the following four principal points. The first point is concerned with the assembly of testing equipment. Problems stemming from framework or lack of control over the testing machine are examined here. Negative effects on test results induced by the Hydraulic cylinder and related oil pressure are investigated and complemented in this section. The second point focuses on the numerical simulation used in order to determine the Bi–axial Tension–Tension Test samples. The specimen geometry given the testing boundary conditions was copied and optimized by means of a Finite–Element–Program (ATENA). The third point is concerned with the notion of “load application”. It was necessary to develop a premise for the loading transmission and connection between steel plates (steel mounting plates) and concrete cogs. The final point takes into account the methods used for measuring the Bi–axial Tension–Tension–test of this work. The second component present in this thesis describes in detail the five Bi–axial Tension–Tension–Tests conducted on AR–Glass TRC plates utilized to prove and ensure the accuracy of the experimental equipment. The TRC plate was built on frame of the bi-axial testing machine and received tensile loading in both directions. This loading relationship was held constant in both directions during the test. Furthermore, the author presents her own thoughts, as well as supplemental commentary, associated with textile reinforced concrete and the resulting experimental outcomes. The last chapter closes this doctoral thesis and includes the abstract of and further prospects for this study. All scientific cognitions are summarised in this chapter.

The Master’s thesis is focused on the analysis and design of selected members of load-bearing structure of an administration building according to the ultimate limit states (ULS) and seviceability limit states (SLS). The calculation and the analysis was supported by design software SCIA ENGINEER 2012. Structural analysis deals with the design of the reinforced concrete (RC) flat slab above the 4rd strorey which is particularly supported by RC columns and particularly lies on RC walls. Furthermore, the Master’s thesis contains analysis of some selected columns of last three storeys, column of lowest storey, construction of stairway between 4rd and 5th storeys. The work beside this deals with the calculation and design of foundation of the object. The rest parts of the load-bearing structure are not solved in the Master’s thesis.

As the main topic this thesis describes the design and evaluation of selected reinforced concrete members of the prefabricated reinforced concrete industrial building with administration at ultimate limit state in accordance with applicable standards. Movable overhead crane with carrying capacity of 50 tons is the main distinction of the industrial hall. Lateral frame whit main structural parts which are roof prestressed girder, load-bearing column supporting the overhead crane and drilled pile transferring loads from the upper construction to the load bearing subsoil, is designed in particular. Furthermore, design of the Gerber beam which forms the slab construction in the administrational part of the building is elaborated. Structural design and evaluation of other structures of the building is not part of this thesis.

The content of the diploma thesis is the processing of a constructive technological project of a business incubator. The objective of this constructive technological project is to approach the construction process in the framework of the study of the implementation of the main technological stages, which closely follows the project of the site construction equipment with suitable layout of its construction, as well as the design of suitable machinery mechanisms for realization of the main building. Part of the project is also to determine the timeliness of work, financial and material management, and technological regulations for implement selected activities, taking into account the quality control and planning of their implementation. The whole construction process is completed in the final part of the diploma thesis on the solution of the occupational health and safety issues.

Glas und Beton sind sich in wesentlichen Materialeigenschaften ähnlich: Beide zeigen gegenüber einer hohen Druckfestigkeit eine vergleichsweise geringe Zugfestigkeit und versagen spröde. Diese Analogie führte zur Entwicklung bewehrter Glasträger, die sich durch eine aufgeklebte Stahllasche an ihrer Biegezugkante auszeichnen. Dadurch wurden die Übertragung von Zugkräften auch im Rissfall möglich, sodass ein duktiles Bauteilverhalten erreicht und der im Konstruktiven Glasbau notwendige Nachweis der Resttragfähigkeit erfüllt wird. Glasträger mit verbundlos vorgespannter Bewehrung – Spannglasträger – stellen die Fortführung dieses Analogiegedankens dar. Neben einer gezielten Steigerung der Erstrisslast, können die Träger planmäßig überhöht werden. Damit wird einer bisher üblichen Überdimensionierung mit der Anordnung nicht ausgenutzter „Opferscheiben“ entgegen gewirkt und sichere sowie materialeffiziente Konstruktionen mit maximaler Transparenz ermöglicht. Diese Konstruktionsweise wurde bislang ausschließlich für einzelne Sondierungsuntersuchungen in breiter Variantenvielfalt genutzt. Eine Systematik und einheitliche Bezeichnungsweise ist nicht vorhanden. Darüber hinaus beschränken sich verfügbare Ergebnisse auf die Beschreibung der Tragfähigkeit, ohne die Resttragfähigkeit explizit zu belegen oder die Dauerhaftigkeit nachzuweisen. Mit dieser Arbeit wurde anhand einer Analogiebetrachtung zum Eurocode 2 eine Bezeichnungsweise für bewehrte und vorgespannte Glasträger entwickelt und für vorhandene Konstruktionen erfolgreich angewendet. Darin zeigt sich, dass der Stand der Technik auf diese Weise charakterisierbar ist. Zusätzlich wird die These aufgestellt, dass sich das Tragverhalten von Spannglasträgern wie im Stahlbeton- und Spannbetonbau beschreiben und die auftretenden Spannkraftverluste analog berechnen lassen. Diese These wird mithilfe experimenteller Studien als Kern dieser Arbeit untersucht und durch eine ergänzende numerische Modellierung bestätigt. Zunächst wird das Tragverhalten im Kurzzeit-Biegeversuch an 15 Prüfkörpern unter variierten Bewehrungsgraden und Vorspannkräften untersucht. Dabei zeigen sich gesteigerte Erstrisslasten sowie ein sicheres Verhalten im Anschluss an die Belastung. Durch die Vorspannung wird das Tragverhalten gezielt beeinflusst. Zusätzlich erbringt eine zerstörungsfreie Untersuchungsreihe an 28 Prüfkörpern unter konstanter Gebrauchslast über 1000 Stunden erstmals eine Beschreibung der auftretenden Spannkraftverluste. Diese sind maßgeblich von der horizontalen Durchbiegung sowie der daraus resultierenden Belastung der Zwischenschicht im Verbund-Sicherheitsglas abhängig. Aus der Größenordnung der Verluste lässt sich schlussfolgern, dass eine Begrenzung dieses Verformungsanteils sowie eine konstruktive Entlastung der Zwischenschicht notwendig sind. Zudem wird die Änderung der Vorspannkraft unter einer Temperaturlast beschrieben. Im Ergebnis zeigt sich, dass dieser Lastfall mittels der linearen Balkentheorie beschreibbar und der damit assoziierte Spannkraftverlust berechenbar ist. Die Resttragfähigkeit von 24 Spannglasträgern wird mithilfe eines eigens entwickelten Prüfverfahrens bestätigt. Während die Bewehrung einerseits eine Überbrückung von Rissflanken ermöglicht, verursacht die Vorspannkraft andererseits im teilzerstörten Tragsystem bisweilen ein frühzeitiges Versagen. Daher wird empfohlen, die baukonstruktive Detailentwicklung zu intensivieren, um einen größeren Sicherheitsvorteil aus der Konstruktionsweise zu generieren. Die Arbeit beinhaltet erstmals eine systematische Datensammlung zum Tragverhalten von Spannglasträgern. Es zeigt sich, dass auf eine Anordnung von „Opferscheiben“ zugunsten einer steigenden Materialeffizienz nicht nur verzichtet werden kann, sondern im Sinne eines effektiven Tragverhaltens verzichtet werden muss. Mit der vorgeschlagenen Bezeichnungsweise, den abgeleiteten konstruktiven Maßnahmen sowie den gezeigten Untersuchungsmethoden besteht nunmehr die Möglichkeit, sichere und dauerhafte Spannglasträger zu entwerfen und deren Trageffizienz zu belegen
Glass and concrete share essential material characteristics: Their compressive strength exceeds their tensile strength considerably and both of them fail in a brittle manner. This analogy led to the development of reinforced glass beams, which are improved by means of adhesively bonded steel sections in the tensile zone. This improvement allowed for a direct transfer of tensile loads in a post-breakage state and resulted in a ductile structural element, which met the special demand of structural glass for a sufficient residual loadbearing capacity. Glass beams with unbonded, post-tensioned reinforcement – Spannglass Beams – carry this analogy concept on. The members will comprise an increased initial fracture strength and may be uplifted intentionally. This development has rendered the need for over-dimensioning by removing unnecessary sacrificial layers, which will result in a material efficient structure and will maximise transparency. Solely single exploratory investigations have used this idea in a wide variety of options so far. There is neither a uniform classification nor a consistent nomenclature. Furthermore, available results are limited to the concise description of the short-term load-bearing properties without proving the residual load-bearing capacity explicitly and confirming longterm durability. This thesis describes the development and the application of a nomenclature for reinforced and pre-compressed glass beams in an analogy study according to Eurocode 2. The state of technology can be characterised in this manner. Additionally, the research describes the load-bearing behaviour as well as the calculation of the loss of pre-stress of Spannglass Beams by analogy with concrete structures. As the key section of this thesis, this statement is examined by means of comprehensive experimental studies and completed by a numerical calculation. Primarily, the load-bearing behaviour of 15 specimens in short-term bending tests and a variety of reinforcement ratios and pre-stress levels were determined. The results show an increase of initial fracture strength as well as safe behaviour after failure. The pre-stress changes the load-bearing performance significantly. Furthermore, a non-destructive study including a constant loading for 1000 h describes the loss of pre-stress in 28 specimens for the first time. The horizontal deflection and the thus resulting shear stresses of the interlayer material of a laminated glass section are the critical parameters. From the magnitude of losses it may be concluded that the deflections need to be limited and the interlayer foils need to be relieved from stress. Moreover, the structural response during a change in temperature is in good agreement with the results obtained from linear beam theory. This allows for an estimation of the associated losses. Finally, a specifically developed test approach confirms the residual load-bearing capacity of 24 specimens. The reinforcement shows the ability to bridge cracks in the glass. However, it should be noted that pre-stress occasionally causes an early failure of the partially broken Spannglass cross-section. Therefore, intensifying the development of structural details in order to generate an increased advantage concerning safety is recommended. This contribution contains a systematic acquisition of analytical, experimental and numerical data regarding the loadbearing characteristics of Spannglass Beams for the first time. The use of a sacrificial layers is not necessary. Even more, to reach the most effective load-bearing behaviour, it is necessary to abandon them completely. Implementing the developed nomenclature, realising the recommended structural provisions and using the proposed methods, it is now possible to compose safe and durable Spannglass Beams as well as prove their structural efficiency

Das Trag- und Verbundverhalten textiler Bewehrungen wurde in den vergangen Jahren umfassend experimentell untersucht. Die dabei gewonnenen Erkenntnisse stützen sich jedoch fast ausschließlich auf einaxiale Beanspruchungszustände. Grundsätzlich können aus dem Vergleich von Versuchen an Rovings und an textilen Bewehrungsstrukturen Rückschlüsse auf den Einfluss der Quer- und Stützfäden und der verschiedenen Bindungstechniken auf das einaxiale Tragverhalten von Textilbeton getroffen werden. Offen bleibt jedoch, inwieweit sich die gefundenen Gesetzmäßigkeiten auf mehraxiale Beanspruchungssituationen übertragen lassen. Dadurch werden Fragen bezüglich des Tragverhaltens textiler Bewehrungen unter mehraxialen Zugbeanspruchungen aufgeworfen, welche die Motivation für die vorliegende Arbeit liefern. Die hierzu durchgeführten experimentellen Untersuchungen umfassen 84 Einzelversuche und wurden in einem speziell für zweiaxiale Zugbeanspruchungen entwickelten Versuchsaufbau durchgeführt. Als textile Bewehrungen kamen zwei verschiedene Gelegearten aus AR-Glas und Carbon zum Einsatz. Die Ergebnisse konnten die bisher ausschließlich an einaxialen Dehnkörpern gewonnenen Erkenntnisse über das Tragverhalten textiler Bewehrungen grundsätzlich bestätigen. Für den Übergang von Zustand I zum Zustand II konnte eine Abhängigkeit der Erstrissspannung vom Spannungsverhältnis nachgewiesen werden. Die Merkmale der Zustände IIa und IIb zeigen hingegen keine signifikante Abhängigkeit vom Verhältnis aus Längs- und Querzugspannung. Darüber hinaus haben offenbar durch Querzug induzierte bewehrungsparallele Risse keine maßgeblichen Auswirkungen auf das Verbundverhalten der Rovings in Längsrichtung. Eine wesentliche Erkenntnis aus den biaxialen Zugversuchen mit Carbon betrifft den Einfluss der Welligkeit. Es wurde deutlich, dass der Abbau der Welligkeit in beschichteten textilen Bewehrungen hochgradig lastabhängig ist. In zahlreichen Versuchen mit Carbon kam es innerhalb des Zustands IIb zu Delamination, einem bisher in diesem Umfang nicht beobachteten Effekt. Die Erkenntnisse hinsichtlich des Abbaus der Welligkeit wurden im Anschluss auf das Tragverhalten von AR-Glas übertragen und führten zu einer Neubewertung des bei AR-Glas beobachteten Steifigkeitsdefizits im Zustand IIb. Weiterhin wurde der Einfluss der Orientierung der Bewehrung unter einaxialer Beanspruchung an scheibenartigen Probekörpern untersucht. Es zeigte sich, dass die untersuchten Bewehrungen aus AR-Glas hinsichtlich der Tragfähigkeit bei schiefwinkliger Beanspruchung deutlich unempfindlicher reagieren als Bewehrungen aus Carbon. Für die Reduktion der effektiven Faserbruchspannungen wurde ein mathematisches Modell vorgestellt, welches eine getrennte Beschreibung der geometrischen Einflüsse sowie alle sonstigen, die Faserbruchspannung reduzierenden Effekte erlaubt.
The load bearing and bond behaviour of textile reinforcements has been comprehensively studied experimental in recent years. The findings are based almost exclusively on uniaxial loading. Generally, from the comparison of tests on rovings and fabrics conclusions can be drawn about the influence of transverse and supporting threads and different binding patterns on the uniaxial load-bearing behaviour. However, it remains open, to what extend the found principles are applicable to multi-axial loading situations. This raises questions about the load bearing behaviour under multi-axial tension loading, which provide motivation for this work. For the experimental studies on 84 specimens a specially developed test setup for biaxial tensile loading was used. Two different types of textile reinforcements made from AR-glass and carbon fibres were examined. The results generally approve the findings on the structural behaviour of textile reinforcements exclusively derived from uniaxial tests. A relationship between first cracking stress level and biaxial stress ratio has been found. The characteristics of the cracking phases and during stabilized cracking, however, show no significant dependencies on the ratio of longitudinal and transverse tensile stresses. Furthermore, parallel cracks induced by transverse tensile stresses have no significant impact on the bond behaviour of longitudinal rovings. An essential result from biaxial tensile tests with carbon is the strong influence of waviness. It became clear that the reduction of waviness in coated textile reinforcement is highly load-dependent. In numerous experiments with carbon reinforcement delamination occurred during stabilized cracking – an effect, that has been observed in this large scale for the first time. The findings regarding the reduction of the waviness were subsequently applied to AR-glass and led to a revaluation of the known stiffness deficit in the phase IIb. Furthermore, the influence of reinforcement orientation has been studied on discoidal specimens under uni-axial loading. It was found that the load bearing capacity of carbon reinforcement is much more sensible to load orientation than AR-glass. A mathematical model was presented, which allows the separate description of geometric factors and as well as all other effects that reduce the fibre tensile strength.