Building tall has always been an expression of dreams, power and technical advancement. With the greatly increasing urbanization in recent years building tall has become a more viable option for office and residential housing. The Tubed mega frame concept tries to evolve the stabilizing systems of high-rise buildings with its mega frame around the buildings perimeter, created together with a new elevator system; the Articulated Funiculator. This thesis examines the effectiveness of the Tubed mega frame compared to other structural systems. Information and background has been taken from different types of literature, analysis programs and verbally from supervisors; Fritz King and Peter Severin. Using Finite Element Method (FEM-) programs studies on previously used structural systems along with the Tubed mega frame has been made, trying to draw conclusions about its advantages and drawbacks. The examinations have been done using SAP2000and ETABS, both developed by CSI. The tubed mega frame shows to require a large amount of concrete compared to other systems at lower heights, because of its geometry. As the height increases it does show an increase in effectiveness and by the time it reaches 480 meters it is using less materials and still achieving greater stiffness than other systems. Since the geometry of the Tubed mega frame is so flexible a conclusion is also made that the stiffness can be increased by sacrificing façade area or creating longer outriggers.

Most of the tall buildings that are built today have a straight and vertical shape, because vertical buildings are more stable and easily built than slanted ones. In the case of vertical building, bending moments in the base only exists from horizontal loads such as wind and seismic loads, but in slanted buildings there will also be bending moments from dead and live loads. In addition, transportation inside the building is also a challenge when it comes to slanted buildings. However, a new elevator system that ThyssenKrupp has developed will solve that problem. This new elevator has an ability to move in all direction both vertically and horizontally. The new structural system, Tube Mega Frame (TMF), has been studied and proved to have better efficiency than the central core with outriggers. Moving the bearing structure to the perimeter of the building, gives smaller overturning moment and better stability due to longer lever arm from the center. This thesis focuses on applying the Tube Mega Frame system to a slanted building which has a tripod structure. Different types of TMFs were used to compare the efficiency of the buildings performance. The TMF contains perimeter frame and mega columns with different binding systems such as belt walls and bracings. A pre-study has been carried out in order to see the overall behavior of the tripod shape. Different heights and inclinations have been analyzed with stick models. The analysis has been performed in the finite element software SAP2000 and deflections due to dead load was compared. The buildings with least deflection considering maximum height and maximum inclination was chosen for further model analysis in finite element software ETABS. Furthermore, a short study of different bracings system has been performed for the lateral loads and it concluded that X-bracing have better performance. The main study of this thesis focused on the two building models of 450 m with 7° inclination and 270 and 15° inclination. For each model, five different TMF systems were applied and analyzed. The TMF includes perimeter frame, perimeter frame with belt wall, mega columns, mega columns with belt wall and mega columns with bracings. Deformations due to wind load, seismic load and modal vibration has been compared. It concluded that the least deformation is achieved by the TMF mega columns with bracings for both models with two different heights. The periods of the building are comparatively lower than other systems. The deflection from TMF mega columns with belt walls did not differ much from the TMF mega columns with bracings. For the 270 m high building, the top story displacement was remarkably small because of the three legs, making it stiffer and stable. Even with the p delta effect, there were only millimeters of difference in top story displacement. TMF perimeter frame had a lower deflection than with belt wall, which should have been exact opposite. The reason was while making the total volume of buildings equal, the addition of belt walls led to thinner columns in the perimeter and lower stiffness.

The need for tall buildings will increase in the future and new building techniques will emerge to full fill that need. Tyrénshas developed a new structural system called Tube Mega Frame where the major loads are transferred to the ground through big columns located in the perimeter of the building. The new concept has the advantage of eliminating the core inside the heart of the building but furthermore gives countless possibilities and flexibility for a designer. The elimination of the central core, plus the multiformity the Tube Mega Frame, can result new building shapes if combined with new inventions like the Multi elevator Thussenkrupp developed. Multi is a new elevator system with the ability to move in all directions apart from vertically. In this thesis research of the possible combinations between TMF and Multi was conducted. The building shaped resulted is only one of the many possible outcomes which the mix of Multi and TMF can have. The building was constructed in a way so the TMF would be the main structural system, the building would have inclinations so the multi elevator would be the only elevator appropriate for the structure and the height would be significantly large. The pre-study focused on the inclination and its particularities. The inclination played a significant role on how the inner forces were distributed in a structure. Under special circumstances the inclination could be even beneficial although inclination could result in axial forces on the slabs so the horizontal elements should be designed thoroughly not only for bending or shear but also for axial loading. The next phase was experimenting on different simple shaped buildings and combinations of them. The conclusions on the simple buildings formed the idea on how the main building would be. The main building was modeled using four different structural systems and their subcategories with seven models in total. Totally seven systems were compared in load combinations for wind, dead, live, and seismic loads and the global behavior was studied. The model comparison included maximum deformations and modes of vibrations. This way the best structural systems were discovered for the specific building shape and conclusions on inclination into a structure were made. The best structural systems and more reliable in terms of results but also in simplicity of construction were chosen to be designed in ETABS. The 50m belt system, the outside braces system and the diagrid system were designed. The design of the buildings was conducted using the American code ASCE /SEI 7-10. In the design two different mega columns were used to study how a solid or hollow cross section can affect the global behavior. Depending on the structural system the mega column had a major or minor effect on the stiffness of the structure. The design of the cross sections was divided in many groups since the complex geometry had an impact on how and where forces arised in the structure. The outside brace system had the best results in terms of less weight and global stiffness proving that in inclined building and columns with the correct bracing and triangulation of elements could extinguish the negative effects of inclination and even perform better compared to conventional buildings.  The 50-belt system was furthermore studied in buckling since it was one of the best structural systems but with the least bracing, but also the least complex in terms of construction method. The automated buckling through ETABS was conducted and a more conservative approach where the user is defining the buckling length and support factors was used. In addition, a comparison between the user defined factors and global buckling was conducted. / Behovet av höga byggnader kommer att öka i framtiden och ny byggteknik kommer att uppfylla detta behov. Tyréns har utvecklat ett nytt konstruktionssystem som kallas Tube Mega Frame där de stora lasterna överförs till marken genom stora pelare i byggnadens omkrets. Det nya konceptet har fördelen att eliminera kärnan inuti byggnadens hjärta, men ger dessutom otaliga möjligheter och flexibilitet för en konstruktör. Avlägsnandet av den centrala kärnan, plus mångfalden av Tube Mega Frame, kan resultera i nya byggnadsformer i kombination med nya uppfinningar som Multi Lift ThyssenKrupphar utvecklat. Multi är ett nytt hissystem med möjlighet att röra sig i alla riktningar bortsett från vertikalt. I denna uppsats genomfördes forskning om möjliga kombinationer med TMF och Multi. Den formgivna byggnaden är bara ett av de många möjliga resultaten som blandningen av Multi och TMF kan ha. Byggnaden byggdes på ett sätt att TMF skulle vara det huvudsakliga struktursystemet, byggnaden skulle ha lutningar så att Multi skulle vara den enda lösning som är lämplig för konstruktionen och höjden skulle vara betydligt stor. Förstudien fokuserade på lutningen och dess särdrag. Lutningen spelar en viktig roll för hur de inre krafterna fördelas i en struktur. Under speciella förhållanden kan lutningen vara till och med fördelaktig, även om lutning kan resultera i axiella krafter på plattorna så att de horisontella elementen måste utformas noggrant, inte bara för böjning eller skjuvning. Nästa fas var att experimentera på olika enkla lutande bygg former och kombinationer av dem. Slutsatserna från dessa enkla byggnaderna bildade tanken på hur huvudbyggnaden skulle vara. Huvudbyggnaden modellerades med fyra olika strukturella system och deras underkategorier med totalt sju modeller. Hela sju system jämfördes i lastkombinationer med vind last, seismisk last, egenvikt, nyttig last och det globala beteendet studerades. Modellens jämförelse inkluderade maximala deformationer och vibrationer. På detta sätt upptäcktes de bästa strukturella systemen för den specifika byggformen och slutsatser om lutning i en struktur gjordes. De bästa strukturella systemen och mer tillförlitliga vad gäller resultat men också avseende enkel konstruktion valdes att utformas i ETABS. 50 m Bältessystemet, det yttre Bäcksystemet och Diagridsystemet konstruerades. Utformningen av byggnaderna utfördes med användning av den amerikanska normen ASCE / SEI 7–10. I designen användes två olika megapelare för att studera hur en solid eller ihålig tvärsektion kunde påverka det globala beteendet. Beroende på konstruktionssystemet kunde megapelaren ha en större eller mindre effekt på strukturens styvhet. Tvärsnittens konstruktion var uppdelad i många grupper eftersom komplexa geometrin har en inverkan på hur och där krafter uppstår i strukturen. Utvändiga stödsystem hade de bästa resultaten när det gäller mindre vikt och global styvhet, vilket viste att i lutande byggnader och pelare kunde den korrekta förstärkningen och trianguleringen av element skilja de negativa effekterna av lutning och till och med fungera bättre jämfört med konventionella byggnader. 50-bältesystemet studerades vidare förknäckning, eftersom det var ett av de bästa konstruktionssystemen, men med minst fackverk, men också det minst komplexa med avseende på konstruktionsmetod. Den automatiska knäckning analysgenom ETABS genomfördes och ett mer konservativt tillvägagångssätt där användaren definierar knäcklängden och stödfaktorerna. Dessutom genomfördes en jämförelse mellan de användardefinierade faktorerna och global knäckning.

The Tubed Mega Frame (TMF) is a structural system for high-rise building developed by Tyréns AB. Compared to conventional structural systems, the TMF is a coreless system that transfers the loads through the perimeter of the building instead and in turn enables ability to support new architectural shapes and forms of buildings. This thesis covers an initial study of a high-rise building with an unconventional shape implementing the TMF system, the Cable-stayed Building, which consists of a slanted tower with a cable-supported cantilever. The study of the building was divided in to a geometrical study and a cable study. The geometrical study was carried out to gain an initial understanding of the global structural behavior by altering specific geometrical parameters. The cable efficiency in terms of total vertical forces was investigated in the cable study by comparing different cable arrangements, cable diameters and prestressing forces for a fixed global geometry. The studies were performed under linear and nonlinear static conditions using the finite element software SAP2000 and ETABS. The results from the geometrical study showed that the cable efficiency increases in terms of larger vertical cable forces with a less inclined building and longer cantilever length. In addition, the results showed significant effects of geometric nonlinearities considering P-delta for different geometric cases. Furthermore, a study of the axial forces in the mega columns indicated that the most inclined building in which no uplifting forces and barely any tension occur along the mega columns, is the 7° incline with cantilever length 73.4 m. As abovementioned, the efficiency of the cables was compared for different arrangements, cable diameter and prestressing forces. The results indicated that as the prestressing force increases, the efficiency of cables rises more for smaller cable diameter than for larger. Furthermore, the comparison of fan- and harp-shape cable arrangements showed that the latter, including three pairs of cables, gives the highest cable efficiency relative to the amount of steel required of the cantilever bracing system. Nevertheless, the study indicates that the cable forces are inherently dependent on many parameters, such as the sag effect considered in the modulus of elasticity and the stress inducing temperature, which in turn depends on cable diameter, prestressing force and cable arrangement. To conclude the study, a modal analysis showed that the Cable-stayed Building is classified as a stiff building according to the guidelines from Council on Tall Buildings and Urban Habitat. Further research on the structure could be carried out within different areas, as this thesis is only an initial study of the structure. For instance, material nonlinearities, dynamic responses of the building as well as soil structure interaction, should be investigated further. / Tubed Mega Frame (TMF) är ett bärande system för höghus utvecklat av Tyréns AB. TMF är, till skillnad från nuvarande konstruktioner, ett system utan en bärande kärna som överför laster via byggnadens perimeter istället, vilket skapar nya förutsättningar gällande arkitektoniska former på höghus. I detta projektarbete genomförs en förstudie på en byggnad med en ovanlig design, Snedkabel Byggnaden, bestående av ett lutande torn och en konsol som bärs upp av kablar.  Studien är uppdelad i en geometrisk analys och en kabel analys. Den geometriska studien syftar till att få en uppfattning om hur det globala bärande systemet beter sig genom att variera vissa geometriska parametrar. Syftet med kabel studiens är att undersöka kablarnas effektivitet genom att jämföra den totala vertikala kabelkraften med olika kabelsystem, kabeldiametrar och förspänningar för en fastställd geometri av byggnaden. Statiskt linjära och ickelinjära strukturanalyser genomfördes för båda studier i finita element programmen SAP2000 och ETABS. Resultaten från den geometriska studien visade att kabel effektiviteten ökar för en mindre lutad byggnad och en längre konsol, då kabelkrafterna ökar. Dessutom indikerar resultaten anmärkningsvärda effekter vid beaktandet av ickelinjäritet med P-delta för olika globala geometrier. En undersökning av axialkrafter i pelarna visar att den mest lutade byggnaden som inte ger upphov till upplyftande krafter och knappt några dragkrafter längs pelarna är byggnaden med 7° lutning och konsollängd på 73.4 m.   Som tidigare nämnt undersöktes kablarna effektivitet genom att jämföra olika kabelsystem, kabeldiametrar och förspänningar. Resultaten påvisade att med högre förspänningar, desto mer ökar kabeleffektiviteten för mindre kabeldiameter än större. Dessutom visade jämförelsen mellan solfjäder- och harp-systemet att harp-systemet med tre kabelpar ger stört kabeleffektivitet i relation till stålmassan för stagningen i konsolen. Krafterna i kablarna beror i sig till stor del av exempelvis elasticitets modulen med hänsyn till kablarnas nedböjning och den spänningsinducerande temperaturen, som i sin tur beror på kabeldiameter, förspänning och kabelsystem. Avslutningsvis utfördes en modalanalys som visade på att Snedkabel Byggnaden klassificeras som en styv byggnad enligt riktlinjer från Council on Tall Buildings and Urban Habitat. Ytterligare studier på strukturen kan genomföras inom olika områden, då detta är en förstudie på byggnaden. Exempelvis på vidare forskning är att ta hänsyn till materialens ickelinjäriteter, byggnadens dynamiska respons samt samverkan mellan byggnad och grund.

The Tubed Mega Frame is a new structure concept for high-rise buildings which is developed by Tyréns. In order to study the structural performance as well as the efficiency of this new concept, a global analysis of the Tubed Mega Frame structure is performed using finite element analysis software ETABS. Besides, the lateral loads that should be applied on the structure according to different codes are also studied. From the design code study for wind loads and seismic design response spectrums, it can be seen that the calculation philosophies are different from code to code. The wind loads are approximately the same while the design response spectrums vary a lot from different codes. In the ETABS program, a 3D finite element model is built and analyzed for linear static, geometric non-linearity (P-Delta) and linear dynamic cases. The results from the analysis in the given scope show that the Tubed Mega Frame structural system is potentially feasible and has relatively high lateral stiffness and global stability. For the service limit state, the maximum story drift ratio is within the limitation of 1/400 and the maximum story acceleration is 0.011m/sec 2 which fulfill the comfort criteria.

A new concept for the structural system for tall buildings, called the “Tubed Mega Frame”, has been developed by Tyréns AB. The structure consists of several hollow reinforced concrete columns at the perimeter of the building and at certain levels, the columns are tied together with perimeter walls. Together they carry all the vertical and lateral loads. A purpose of the new concept is to eliminate the core in the center of the building which allows utilizing more floor spacing compared with other skyscrapers. This kind of structure has never been examined before and thus never been designed for such a large building. In this thesis the vertical hollow concrete columns are designed according to the American concrete design code, ACI 318. A literature study on reinforced concrete columns has been investigated, where the goal was to identify the most critical design aspects for columns in high rise structures, especially utilizing high strength concrete. Since this kind of structure never has been designed before, an evaluation of the ACI 318 has been performed to check if it is possible to design the hollow reinforced columns in the Tubed Mega Frame according to this design code. The loads and forces used for the design were extracted from a global finite element model in ETABS of a concept prototype of 800 meter. The design process consisted of design calculations according to the ACI 318, a buckling analysis in SAP2000 and a non-linear FE-analysis in ATENA. For the buckling analysis in SAP2000 the lower region of the building was isolated between two main perimeter walls. The model was modified several times to analyze how sensitive the structure was to buckling, with regard to different wall thicknesses, cracked cross-sections, openings in the columns and the dependency of intermediate perimeter walls. The non-linear analysis in ATENA focused on a single hollow column between two perimeter walls in the lower regions of the building. Two models were created, one with a full wall thickness and one with a reduced wall thickness where the ultimate capacity and failure behavior of the columns were investigated. The ultimate capacity of the sections designed by hand calculations and analyzed in ATENA were found to be brittle failure modes. To achieve a more ductile failure, an alternative reinforcement geometry with confining reinforcement has been proposed. The results from the design shows that the structure is redundant against buckling, even with reduced bending stiffness and without intermediate perimeter walls. From the analysis in ATENA, the results demonstrated that the columns are capable of carrying all the ultimate loads even if the wall thickness is reduced by 50%, and that it is possible to use the ACI 318 to design the reinforced concrete columns. However, an unexpected brittle failure occurred in the flanges of the column corners in the tensile region were shear lag may affect the behavior and caused the premature failure. A deductive conclusion has been drawn which states that proper confinement will be critical to achieve a ductile failure behavior even in the tensile region, which will require further studies in order to fully understand the behavior. Even though the results show that it was possible to reduce the cross-sectional thickness of the columns, more studies have to be performed to evaluate if the global structure fulfills the requirements with the decrease in column wall thickness. / Ett nytt strukturellt koncept för skyskrapor har utvecklats av Tyréns AB, "Tubed Mega Frame", där strukturen består av flera ihåliga armerade betongpelare i utkanten som hålls samman med omslutande tvärväggar, och tillsammans bär de alla vertikala och laterala laster. Denna typ av konstruktion har aldrig analyserats eller utformats tidigare. I detta examensarbete är de vertikala ihåliga betongpelarna dimensionerade enligt den amerikanske byggnormen, ACI 318 och de kritiska aspekterna med att utforma ett höghus i höghållfast betong med ihåliga pelare undersökts. Eftersom denna typ av konstruktion aldrig tidigare utformats, har en utvärdering av ACI 318 genomförts för att kontrollera om det är möjligt att dimensionera de ihåliga vertikala pelarna i Tubed Mega Frame enligt denna norm. De laster och krafter som används för dimensioneringen extraherades ur en global finit elementmodell för en konceptbyggnad på 800 meter i ETABS. Den dimensionerande processen bestod av dimensioneringsberäkningar enligt ACI 318, en knäckningsanalys i SAP2000 och en icke-linjär FEM-analys i ATENA. För knäckningsanalysen i SAP2000 isolerades en sektion i den nedre regionen av byggnaden, mellan två omslutande tvärväggar. Modellen ändrades flera gånger för att analysera hur känslig konstruktionen var med hänsyn till knäckning, och de ändringar som gjordes var: minskning av väggtjocklekar, reducering för spruckna tvärsnitt, öppningar i pelarna samt de omslutande mellanliggande tvärväggarnas inverkan på knäckningen av konstruktionen. Den icke-linjära analysen i ATENA fokuserade på en pelare mellan två omslutande tvärväggar i den lägre regionen av byggnaden. Två modeller skapades, en med en full väggtjocklek och en med en reducerad väggtjocklek för att analysera brottbeteendet och verifiera den handberäknade kapaciteten enligt ACI 318. De brottmoder som påträffades för tvärsnittsverifikationen i ATENA var spröda och karakteriserades med krossning av betongen, och för att uppnå ett mer segt brott härleddes en alternativ armeringsgeometri med sammanhållande armeringsbyglar i de mest kritiska regionerna av pelarna. Resultaten visade att konstruktionen är robust mot knäckning, även med minskad böjstyvhet och utan mellanliggande omslutande tvärväggar. Av analysen i ATENA visade resultaten att pelarna är kapabla att bära alla de kritiska lasterna även om väggtjockleken reduceras med 50 % och att det är möjligt att använda ACI 318 som norm för dimensionering av pelarna i Tubed Mega Frame. Dock inträffade ett oväntat sprött brott i den dragna flänsen i nedre regionen av pelaren, framförallt koncentrerat till hörnen. Anledningen till det spröda brottet har utvärderats och analyserats där hypotesen är att flänsskjuvning i kombination med höga spänningskoncentrationerna i hörnen orsakar det lokala brottbeteendet i flänsen. Slutsatsen som baseras på hypotesen är att sammanhållande armeringsbyglar skulle vara avgörande för att uppnå ett segt brottbeteende även för den dragna flänsen. Även om resultaten visade att det var möjligt att reducera tvärsnittstjockleken för pelarna, krävs mer studier för att utvärdera om den globala konstruktionen uppfyller kraven för en minskning av pelarnas väggtjocklekar.

Building engineering is called upon to keep up with the pace and challenges of modern design, which aims not only to build higher and greener, but also to fulfill the demands of the growing population and simple human curiosity. The main purpose of this study was to examine the global behavior of a slender and inclined (V-shaped) 300 m high rise building with different structural systems applied. In order to properly evaluate them, four different parametric studies were conducted. These included determining the appropriate inclination angle and the geometry of a simple beam system and later comparing fourteen different structural systems, namely trusses, diagrids, Tubed Mega Frames and moment frames. Parallel to this, a further investigation was made on a shell and beam element model, in order to assess the simplifications made and to control the obtained results. This study was based on various simulations in Finite Element Analysis programs, primarily ETABS, but also SAP2000 and Autodesk Robot Structural Analysis. The modelling included the definition of geometry and applied loads and results in extracting the desirable forces and deformations. Additionally, the automatic design for structural members was used for the purpose of a comprehensive study of the chosen structural systems. The designed structures were subjected to static analysis (dead, live, wind, seismic load), dynamic analysis (response spectrum and time history function) and nonlinear P-delta effect. A buckling analysis was also performed to determine the modes and associated load factors for buckling. In the end, the structural response in terms of displacement and acceleration was compared. The inclination angle study set the defining angle at 10° from vertical, with respect to the serviceability limit deflection. Comparing alternative truss geometries in a 2D parametric study resulted in the choice of four different systems (X, N, K and W trusses). In the 3D analysis, the chosen truss systems, together with three variations of diagrid systems, and seven Tubed Mega Frames with two moment frame structures were further analyzed. In both groups, the mass and the material of the systems were kept similar and the comparison was basically based on the obtained maximum displacement and natural periods of the buildings. The shell and frame model comparison gave a difference in displacements between 0 and 12%. Finally, the comprehensive study of the Tubed Mega Frame, X truss and diagrid structures showed that these buildings were performing similarly to vertical buildings with a top story displacement within the suggested limits (less than 673 mm). Further investigation should be made concerning the acceleration under synthetic earthquake, which exceeded the suggested norms, as well as the connecting nodes between the trusses and the inclined columns. The outcome of this study implied the possibility of construction and usability of inclined, slender, tall buildings with respect to the Ultimate Limit State and the Service Limit State, as specified in the American standard, ASCE 7-10, and opened new possible issues for further research.

As a response to the ever denser cities, skyscrapers have become yet more popular and are growing more and taller than ever. A new efficient structural system for skyscrapers has been proposed by Tyréns AB, called the Tubed Mega Frame. This structural system consists of hollow concrete tubes at the perimeter of the building. Since this structural system has not yet been used in any skyscraper several aspects have still not been studied or investigated. An important aspect having an impact on the system’s competitiveness compared to traditional structural systems is how a skyscraper using this new structural system could be built. This thesis treats the construction methodology of Tubed Mega Frame structures. The construction methodology of a prototype building is evaluated to connect the findings to a plausible real project. Building very tall concrete structures sets a lot of demands on the concrete used and having an effective construction is essential. The elastic modulus of the concrete has been identified as one of the most important concrete properties why this topic has been studied. Comparisons of the formulas of different codes for estimating the elastic modulus have been made to see what elasticity can be achieved. Concrete recipes that have been used in already built skyscrapers have been reviewed to see what elastic moduli are feasible to reach and expect. Pumping concrete to high levels sets demands on the concretes flowability and self-compacting concrete is necessary to use. Ways of improving the concrete properties are also studied. All studies show that the Tubed Mega Frame structural system would be possible to construct with today’s concrete and pumping technology even though improvements can be expected from future development in concrete technology. As most skyscrapers that are built today, a Tubed Mega Frame structure would preferably be built with a self-climbing formwork system rising one level at a time. From a review of available construction methodologies, the thesis shows that these systems would be applicable on a Tubed Mega Frame structure with minor adaptions of the systems. The floor cycle time, i.e. the time it takes to complete an entire floor before proceeding to the next level, has a significant importance in determining the construction time of a skyscraper. For this reason a floor cycle with all activities related to the structural system and their sequences have been developed for the prototype building. By determining all the relations that are between activities and using productivities for estimating their durations it has been possible to evaluate the time it would take to complete a standard floor. By the use of Microsoft Project the duration of a stated average floor cycle has been estimated to a little more than 4 days. / Som en reaktion på att allt fler människor bor i städer har skyskrapor kommit att växa sig allt fler och högre. Traditionellt har skyskrapor oftast utnyttjat någon form av kärna som stomsystem vilken upptar stor yta av våningsplanen. Som en möjlig metod att göra skyskrapors stomsystem effektivare har Tyréns utvecklat det nya stomsystemet Tubed Mega Frame. Då detta bärande system ännu inte har använts i någon skyskrapa är det ett flertal aspekter som inte har blivit studerade och undersökta. En viktig aspekt som är av stor vikt för systemets konkurrenskraft gentemot mer traditionella system är hur det skulle gå till att bygga en skyskrapa som använder detta nya stomsystem. Det här examensarbetet behandlar byggnationsmetodiken för Tubed Mega Frame. Byggnationen av en prototypbyggnad som använder detta system utvärderades för att koppla resultaten till en möjlig verklig byggnad. Att bygga väldigt höga konstruktioner i betong ställer stora krav på betongen som används, och att ha en effektiv byggnation är också av stor vikt. Betongens elasticitetsmodul har identifierats som en av de viktigaste egenskaperna för betongen och därför har detta område studerats djupare. En jämförelse av hur olika normer beräknar elasticitetsmodulen har gjorts och vilka elasticitetsmoduler det ger. De betongsammansättningar som har använts i tidigare skyskrapebyggande har studerats för att se vilka elasticitetsmoduler som kan förväntas. Att pumpa betong till höga höjder ställer stora krav på betongens pumpbarhet. För att göra detta möjligt är det nödvändigt att använda självkompakterande betong. Vilka olika sätt som finns tillgängliga för att styra betongens egenskaper har också studerats. Undersökningarna visar på att det skulle kunna vara möjligt att med dagens betong och pumpteknologi bygga en skyskrapa som använder Tubed Mega Frame som bärande system. Med framtida framsteg inom betongteknologi kan man även förvänta att bättre lämpad teknik kommer att utvecklas. En skyskrapa med stomsystemet Tubed Mega Frame skulle liksom de flesta av dagens skyskrapor lämpligtvis byggas med hjälp av självklättrande formsystem, och därigenom bygga en våning i taget. Studier av teknik och byggnationsmetoder som finns tillgängliga idag har visat på att dagens teknik skulle vara möjliga att applicera på Tubed Mega Frame med endast mindre justeringar. Det som har ett stort inflytande på byggtiden av en skyskrapa är våningscykeltiden, d.v.s. den tid det tar att bygga en våning innan det är möjligt att fortsätta på nästa. Av denna anledning har en våningscykel med alla relevanta moment som ingår blivit bestämd och utvärderad för prototypbyggnaden. Genom att ha klargjort alla relationer mellan olika aktiviteter och den tid de tar att utföra har det varit möjligt att utvärdera den tid en hel våningscykel skulle ta. Med hjälp av Microsoft Project har en våningscykel för en våning som bedömts som representativ för hela prototypbyggnaden kommit att ta drygt fyra dygn.

A recent development and innovation in elevator technologies have sprawled interest in how these technologies would affect the forms and shapes of future high-rise buildings. The elevator that uses linear motors instead of ropes and can thus travel horizontally and on inclines is of particular interest. Once the vertical cores are no longer needed for the elevators, new and radical building forms and shapes are anticipated. It is expected that the buildings will have bridges and/or the buildings themselves will structurally perform more like bridges than buildings, therefore this study addresses the following topic - structural design and performance of tube mega frame in arch-shaped high-rise buildings. Evidently, for a structure of an arched shape, the conventional structural system used in high-rise buildings does not address the structural challenges. On the other hand, The Tubed Mega Frame system developed by Tyréns is designed to support a structural system for high-rise building without the central core, in which the purpose is to transfer all the loads to the ground via the perimeter of the building, making the structure more stable by maximizing the lever arm for the structure. The system has not yet been realized nor tested in realistic circumstances. This thesis aims at evaluating the efficiency of the Tubed Mega Frame system in arched shaped tall buildings. Multiple shapes and type of arches are evaluated to find the best possible selection. Structural behavior of different arch structures is studied using analytical tools and also finite element method in software SAP2000. The most efficient arch shape is sought to distribute the self-weight of the structure. The analysis shows that it is possible to accurately determine efficient arch shape based on a specific load distribution. Furthermore, continuing with the arch shape found in previous steps, a 3D finite element model is built and analyzed for linear static, geometric non-linearity (P-Delta) and linear dynamic cases in the ETABS software. For the given scope, the results of the analysis show that the Tubed Mega Frame structural system is potentially feasible and has relatively high lateral stiffness in the plane of the arch, while the out-of-plane lateral stiffness is comparatively smaller. For the service limit state, the maximum story drift ratio is within the limitation of 1/400 for in-plane deformations, while for out-of-plane the comfort criteria limit is exceeded.

The Tubed Mega Frame is a new concept for constructing high-rise buildings,based on the idea of moving the main bearing system to the perimeter of thebuilding by using a number of large hollow columns, mega tubes, connected byperimeter walls at certain levels. The concept is under development by Tyréns ABand has not yet been implemented in reality. This thesis is part of the ongoing workprocess and has the aim of shedding light on the issues and problems with the newconcept when it comes to the perimeter walls. The perimeter walls are an essential part of the Tubed Mega Frame structure sincethey provide the main lateral stability of the structure by connecting the mega tubesand transferring lateral loads between them. It is therefore of big importance thatthe walls are designed and constructed to withstand all the loads they wouldpossibly be exposed to.In this thesis a perimeter wall in a prototype building of the Tubed Mega Framehave been analysed, designed and tested using non-linear FE-analysis in the pursuitof create a better understanding in how the perimeter walls works and should bedesigned. To begin with, a global analysis was performed to obtain the forces acting on themost critical perimeter wall. The stresses in the wall were then analysed in order tocreate an appropriate strut-and-tie model used to determine the reinforcementdesign for the specified perimeter wall. The perimeter wall was designed for amaximum shear force of 14.5 MN and corresponding moment of 87 MNm usingstrut-and-tie model according to American standards, ACI 318-11. The final step was to verify the design using the non-linear FE-analysis programATENA. A model of the reinforced wall was analysed with two different loadcases; one were the resistance was determined by unidirectional deformation untilfailure and one were the effects of cyclic loading was considered by initialdeformation corresponding to service loads prior to failure loading. The resistanceobtained from the first load case was 46.8 MN and for the second 19.1 MN usingmean values for material properties. In order to obtain a design resistance of the wall in the non-linear analysis, a globalsafety factor was determined by using the ECOV method. The design resistance were 39.9 and 13.5 for the two load cases respectively. / Tubed Mega Frame (TMF) är ett nytt koncept för att bygga höghus som bygger påidén om att flytta det bärande systemet till omkretsen av byggnaden med hjälp avett antal stora ihåliga pelare, megatuber, anslutna med omslutande tvärväggar påvissa våningsplan. Konceptet är under utveckling av Tyréns AB och har ännu integenomförts i verkligheten. Detta examensarbete är en del i den pågående processenoch målet är att belysa frågor och problem som finns med det nya konceptet närdet gäller de omslutande tvärväggarna. De omslutande tvärväggarna är en vital del av Tubed Mega Frame eftersom debidrar till huvudsakliga sidostabiliteten i byggnaden genom att sammankopplamegatuberna och överföra horisontalkrafter mellan dem. Det är därför av stor viktatt väggarna är konstruerade och tillverkade för att stå emot alla de belastningarsom de skulle kunna vara utsatta för. I detta examensarbete har en tvärvägg i en prototypbyggnad för Tubed MegaFrame analyserats, dimensionerats och testats med syftet att bidra till en bättreförståelse för hur tvärväggarna fungerar och bör utformas. Till att börja med har en global analys utförts för att erhålla de krafter som verkarpå den mest kritiska tvärväggen. Spänningarna i väggen analyserades sedan för attskapa en lämplig fackverksmodell som sedan användes för att bestämmaarmeringsutformning för den specificerade tvärväggen. Väggen dimensioneradesför en maximal tvärkraft på 14,5 MN och ett motsvarande moment på 87 MNmgenom att använda fackverksmetoden enligt amerikanska standarder, ACI 318-11. Det sista steget var att kontrollera konstruktionen med hjälp av det ickelinjära FE-analysprogrammet ATENA. En modell av den armerade väggen analyserades medtvå olika lastfall. I det första lastfallet genom att i en riktning deformera väggen tillbrott. I det andra lastfallet beaktades tidigare uppsprickning genom att först belastaväggen med en deformation motsvarande dess brukslast och sedan belasta väggen imotsatt riktning tills brott uppstod. Bärförmågan var 46,8 MN och 19,1 MN förrespektive lastfall, beräknat med medelvärden för materialegenskaper. För att erhålla en dimensionerande bärförmåga för väggen ur den ickelinjäraanalysen bestämdes en global säkerhetsfaktor med hjälp av ECOV-metoden.Dimensionerande bärförmåga var 39,9 MN och 13,5 MN för respektive lastfall.