Purpose: Throughout the years numerous studies have been made that concludes thatcombining steel and wood results in improved strength. Under optimal conditions woodis an effective structural material, as it’s both cheap and durable. Steel on the other handunder right circumstances has considerably higher strength than wood. To combinewood and steel has over the last years gathered more attention. Studies shows thathybrid structures can lead to an economical advantage when building multiple storeybuildings, as it can replace or complete pure steel frames. The purpose of this paper isto increase the knowledge and understanding of how steel and wood cooperate and tofind out the advantages and disadvantages of using a flitched beam, as well as compareit’s strength to structural wood and glulam.Method: The paper comprises a quantitative study with two different kinds of datacollection methods, Literature studies and calculations. The literature study consists ofscientific papers and papers published by known institutions and will help the paperanswer the first issue. The calculations has been made with the help of Tekla Tedds,which follows the Eurocode design principles. Which will help the authors answer bothof the papers issues.Findings: The paper has found that the flitch beam has improved strength overstructural wood and glulam, but a significantly higher price. The flitch beam also has amuch higher self weight than structural wood and glulam. The flitch beam can also spanlonger than structural wood and glulam with the same applied load.Implications: The study have concluded that it’s hard to motivate the usage of flitchedbeams in floor designs as they have such high price. The flitch beam has higher strengththan both structural wood and glulam. Which makes the flitch beam a good option asload bearing beam that requires slim dimensions. The added strength of the flitch beamcan motivate the high price under the right circumstances.Limitations: The paper has limited the calculations to an enclosed environment andwill not take moisture or any other type of exposure in to account, As a dry indoorenvironment is optimal for both steel and wood. The calculations the paper uses arebased on Eurocode and all other forms of dimension principles will not be taken intoaccount. / Syfte: Genom åren har forskning gjorts som tyder på att när man kombinerar stål ochträ kommer det bidra till en ökad hållfasthet. Under optimala förhållande är trä ettotroligt effektivt och bra alternativ inom byggande då det är billigt och tåligt. Närstålbalkar däremot placeras i optimala förhållande kan de bibehåll betydligt mer ochstörre krafter än vad trävirke kan göra. Att kombinera stål och trä har de senaste årethaft ett ökat intresse. Studier visar att hybridbalkar kan vara till stor ekonomisk fördelvid byggnation av flervåningshus, då det kan ersätta eller komplettera rena stålstommar.Syftet med arbete är att öka kunskapen och förståelsen för hur stål och trä samverkarsamt ta reda på för och nackdelar hos de stålförstärkta träbalkarna samt jämföra deraslastkapacitet med konstruktionsträ- och limträbalkar.Metod: Arbetet omfattar en kvantitativ studie där två typer av datainsamlingsmetoderhar använts. Dessa två typer är beräkningar samt litteraturstudier. Litteraturstudienbestår av vetenskapliga artiklar som har hjälpt besvara en av frågeställningarna.Beräkningarna har använts för att besvara båda frågeställningarna, de har gjorts idimensioneringsprogrammet Tekla tedds som följer alla Eurocodes beräknings- ochdimensioneringsregler.Resultat: Resultaten visar på att den stålförstärkta träbalken har högre kapacitet änlimträ och konstruktionsvirke, både med hänsyn till nedböjning och brott men betydligthögre pris och egentyngd. Den stålförstärkta träbalken klarar även av längrespännvidder vid samma belastning.Konsekvenser: Utifrån de resultat rapporten kommit fram till är det svårmotiverat attanvända sig av de stålförstärkta balkarna i bjälklag på grund av det höga priset Denstålförstärkta träbalken klarar dock av högre laster än vad konstruktionsvirke och limträgör, vilket kan göra balken användbar som avväxlingsbalk. Att använda denstålförstärkta träbalken som avväxlingsbalk kan motivera det höga priset då den kanhålla mindre dimensioner än limträ och konstruktionsvirke vilket kan vara önskvärt iolika sammanhang.Begränsningar: De begränsningar som sattes för rapporten var att utesluta alla typerav miljörisker på balkarna som tillexempel fukt och solljus vid beräkningarna, då entorrmiljö är en optimal miljö för både trä och stål. Beräkningarna som arbetet baseraspå grundar sig på Eurocodes dimensioneringsregler. Andra typer av dimensioneringsprinciper har uteslutits.

Baigiamajame magistro darbe aptarti klijuotosios medienos su įklijuotaisiais plieniniais strypais privalumai bei trūkumai, jų panaudojimas ir taikymas statybos pramonėje. Atlikta plieno strypų, įklijuotų medienoje išilgai, skersai ir kampu į medienos pluoštus, teorinių skaičiavimų pagal Europos ir Rusijos normas metodikų analizė. Atlikti teoriniai standžios sijos jungties su įklijuotaisiais plieniniais strypais skaičiavimai. Išanalizuota bandymų metodika. Tiriamojoje dalyje atlikti šie eksperimentiniai bandymai: armatūros strypų takumo įtempių nustatymas; medienos tankio ir drėgnio nustatymas; strypų, įklijuotų medienoje išilgai, skersai ir 45o kampu į medienos pluoštus gniuždymo bandymai; sijos standžios jungties su įklijuotaisiais plieniniais strypais bandymas. Nustatyti esminiai rodikliai, veikiantys bandymų rezultatus, irimo pobūdžiai bei elgsena bandymų metu. Skaičiavimų rezultatai palyginti su eksperimentinių bandymų metu išbandytais natūralaus dydžio bandinių rezultatais. Darbe pateikti, įvertinti ir išanalizuoti teoriniai ir eksperimentiniai rezultatai, jų skirtumai. Pateiktos rekomendacijos ir pasiūlymai skaičiavimų metodikų tobulinimui ir praktiniam įklijuotųjų plieno strypų medienoje panaudojimui. / In this master degree paper are discussed advantages and imperfections, practice and use in construction industry of glulam with glued-in steel rods. Theoretical calculations analysis according to Eurocode and Russian standards of glued-in steel rods parallel, perpendicular and at an angle to the grain were made. Theoretical calculations of rigid joint glulam beam with glued-in steel bars were made. Tests methods were analyzed. In the part of the researches these tests were made: yield stress evaluation test of steel rods; moisture and density evaluation tests of wood; parallel, perpendicular ant at an 45 o angle to the grain compression tests of the glued-in steel rods; rigid joint of the glulam beam with glued-in steel rods test. Fundamental factors, which have influence to the results of the tests, character of the disruptions and the behavior of elements during the experiments were defined. The results of the calculations were compared with the results of tests in which natural size specimens were tried. In this work the results of theoretical calculations and experimental tests are proposed, evaluated and analyzed. The reasons of divergence in results are indicated. Recommendations and suggestions how to improve the methods of calculations and for better use the glued-in steel rods in the practice were offered.

Submitted by Claudia Rocha (claudia.rocha@udesc.br) on 2017-12-08T13:57:32Z No. of bitstreams: 1 PGEF16MA066.pdf: 1624060 bytes, checksum: 61f98997f35b2a6f9e48ef3f872a39b6 (MD5) / Made available in DSpace on 2017-12-08T13:57:32Z (GMT). No. of bitstreams: 1 PGEF16MA066.pdf: 1624060 bytes, checksum: 61f98997f35b2a6f9e48ef3f872a39b6 (MD5) Previous issue date: 2016-07-29 / UNIEDU / FUMDES / The geometry of finger joint is one of the most important variables when determining the connection strength among timber with structural use purpose. This research aimed to evaluate three finger joint geometries and its correlation with three species of timber from reforestation and three adhesives used for structural purposes. The species were: Eucalyptus grandis, Pinus taeda and Schizolobium parahyba var. amazonicum (known as paricá), and the adhesives: resorcinol formaldehyde, melamine urea formaldehyde and reactive polyurethane. Finger profiles were produced by means of a spindle moulder, glued and pressed in manufacture plant and laboratory. Then, the specimens were flattened obtaining the dimensions as recommended by NBR 7190/1997. The finger joint geometry was measured with a digital caliper, the specimens were tested and the failure modes determined. Statistical analysis was done by evaluating the geometric means by Tukey test with 95% probability. Results showed that E. grandis produced with resorcinol adhesive from geometry B, had the highest tensile strength parallel to the fibers (67,55 MPa). Also, the higher tensile strength values were from the specimens with higher basic density. As for failure modes, 64% of the specimens failed in modes number 3 (14%) and 4 (50%). It was found that all evaluated factors interfered in the results of resistance and, regarding the determination of the best geometry, specie and adhesive, these can not be analyzed separately / A geometria da emenda por entalhes múltiplos é uma das variáveis mais importantes quando se determina a resistência da ligação entre madeiras com finalidade de uso estrutural. O objetivo da pesquisa foi avaliar três geometrias de emendas por entalhes múltiplos e sua correlação com três espécies de madeira de florestas plantadas e três adesivos utilizados para fins estruturais. As espécies foram o Eucalyptus grandis, o Pinus taeda e o Schizolobium parahyba var amazonicum (paricá), e os adesivos: resorcina formaldeído, melamina ureia formaldeído e poliuretano reativo. Os corpos de prova foram fresados, colados e prensados em parque fabril e em laboratório. Posteriormente, eles foram aplainados obtendo-se as dimensões conforme orientação da NBR 7190/1997. Foram medidas as geometrias com paquímetro digital, realizados pré-testes e determinados os modos de ruptura. A análise estatística foi feita avaliando-se as médias de geometria pelo teste de Tukey a 95% de probabilidade. Dos resultados obtidos, destaca-se a espécie E. grandis produzida com o adesivo resorcina da geometria B, que teve a maior resistência à tração paralela às fibras (67,55 MPa). Também, os maiores valores de tensão foram provenientes dos corpos de prova com maior densidade básica. Quanto aos modos de ruptura, 64% dos corpos de prova romperam pelos tipos 3 (14%) e 4 (50%). Verificou-se que todos os fatores avaliados interferiram nos resultados de resistência e, no que se refere à determinação damelhor geometria, melhor espécie e melhor adesivo, não podem ser analisados separadamente

Depuis quinze ans, on recommence à construire en bois, et notamment en bois lamellé-collé (LC), pour répondre aux nouveaux challenges imposés par les problématiques de développement durable. Néanmoins, des problèmes de dégradations liés à l'humidité ou aux cycles d'humidification/séchage limitent le développement des ouvrages en bois. De ce fait, le suivi de l'humidité des ouvrages d'art en bois devient un enjeu crucial. Aujourd'hui, certaines solutions existent mais ne permettent pas un suivi local au niveau des lamelles du bois LC. Une telle solution permettrait d'améliorer la prédiction de la durée de vie des ouvrages. Suite à ce constat, nous avons proposé de transformer le bois LC en " structure intelligente " par intégration d'un système du suivi de l'humidité au niveau des lamelles, et ce, en tenant compte des principales contraintes de fabrication de ce matériau (faible épaisseur du joint collé, pression de collage importante, etc.). Pour ce faire, nous avons effectué une recherche bibliographique afin de sélectionner les méthodes de suivi pouvant répondre à ces contraintes. A l'issue de cette recherche, deux technologies se sont révélées intéressantes : les mesures électriques et les mesures ultrasonores. Plusieurs configurations de mesures ont été proposées et testées pendant ce travail de thèse. Par la suite, nous avons effectué des essais préliminaires pour s'assurer du bon fonctionnement de ces configurations de mesures, et ainsi vérifier le comportement des capteurs lors de la fabrication du bois LC. Puis, nous avons humidifié les échantillons en utilisant deux protocoles d'humidification différents afin de vérifier la faisabilité du suivi de l'humidité avec les capteurs intégrés. Les résultats montrent que l'ensemble des configurations de mesures sont opérationnelles pour suivre la variation de l'humidité dans les échantillons LC. De plus, pour les mesures électriques, nos résultats montrent que l'on peut adopter quasiment les mêmes modèles d'étalonnage pour le suivi de l'humidité par mesures résistives, quel que soit le type de capteurs utilisé. Qui plus est, il est possible de récupérer des informations complémentaires par la réalisation simultanée des mesures résistives et des mesures capacitives en utilisant les électrodes surfaciques. Concernant les mesures ultrasonores, nous avons obtenu les courbes de sensibilité en fréquence pour plusieurs familles de capteurs à film piézoélectrique. L'influence de la pression de collage et de la distance entre les capteurs sur les mesures électriques/ultrasonores a aussi été investiguée dans ces travaux. De futures études consisteront à utiliser ces configurations de mesures pour le suivi in situ dans les ouvrages, ainsi qu'à établir un lien entre la durabilité des structures LC et les cycles d'humidification/séchage afin de prédire la durée de vie résiduelle des ouvrages d'art en bois. / For fifteen years, we restart to construct with wood, and particularly with glulam to respond to the new challenges imposed by the issues of sustainable development. However, degradation issues related to moisture content (MC) or wetting/drying cycles limit the development of timber structures. As a result, the MC monitoring in timber structures becomes a critical issue. Today, several solutions exist but they do not allow a local monitoring in the lamellas of glulam. Such a solution would improve the prediction of the service life of timber structures. In the light of this observation, we proposed to transform glulam into "smart material" by embedding a MC monitoring system in the lamellas, and this, considering the major constraints of fabrication of this material (small glue line thickness, important bonding pressure, etc.). To achieve this, we have conducted a bibliographic research, in order to select the monitoring methods which can satisfy these constraints. According to this research, two technologies turn out to be interesting: the electrical measurements and the ultrasonic measurements. Several measurement configurations were proposed and tested in this PhD work. Thereafter, we conducted preliminary tests to make sure of the good functionality of these measurement configurations, and also to verify the behavior of sensors throughout the glulam fabrication process. Afterwards, we moistened the specimens with two different moistening protocols in order to verify the feasibility of MC monitoring with embedded sensors. Results showed that all the measurement configurations are operational for the MC monitoring in glulam specimens. Moreover, for electrical measurements, our results show that we can adopt almost the same calibration models for the MC monitoring by resistive measurements, no matter the type of sensors used. Furthermore, it is possible to obtain complementary information by the realization of the resistive and capacitive measurements at the same time, using surface electrodes. Regarding the ultrasonic measurements, we have obtained the sensibility curves in frequency of several families of piezoelectric film sensors. On the other hand, the influence of bonding pressure and of sensor distance on the electrical/ultrasonic measurements was also investigated in this study. Future studies will consist in using these measurement configurations to perform in situ monitoring in timber structures, and also to establish a link between the durability of glulam structures and the wetting/drying cycles in order to predict the service life of timber structures.

No cenário da produção de edificações sustentáveis, a madeira laminada colada (MLC) ocupa lugar de destaque, sobretudo pela possibilidade de emprego de madeiras provenientes de florestas plantadas. Com o propósito de amenizar os problemas de durabilidade, quando exposta às intempéries, uma solução pressupõe a associação das vigas de MLC com um tabuleiro de concreto armado, sendo as partes ligadas por meio de conexões flexíveis. Essa técnica tem sido aplicada com sucesso, especialmente por conta do expressivo acréscimo de rigidez proporcionado pela composição. No entanto, em situações de elevados carregamentos ou de grandes vãos, a aplicação de reforços com fibras sintéticas, na face tracionada das vigas de MLC, aprimora ainda mais essa técnica, refletindo-se em significativos acréscimos nas forças de ruptura. Neste trabalho avaliou-se, de forma experimental e numérica, o comportamento estrutural de vigas mistas de MLC-concreto reforçadas com fibras de vidro. Numa primeira etapa foram estudados os elementos de ligação, optando-se pelos ganchos de aço com diâmetro de 8 mm pelo seu excepcional desempenho. Em seguida foram confeccionadas as vigas mistas, com e sem reforços com fibras de vidro, registrando-se acréscimo médio de 37% no módulo de ruptura (MOR) das vigas mistas em relação às vigas de MLC, ambas reforçadas com fibras. O emprego do reforço com fibras sintéticas se justifica pela diminuição na dispersão dos resultados. Por fim, um algoritmo foi proposto para o dimensionamento das vigas mistas de MLC-concreto reforçadas com fibras de vidro, o qual, associado às avaliações numéricas e experimentais, permite ampliar os horizontes de aplicação das estruturas de madeira. / Production of sustainable constructions forms a scenario where glulam beams occupy a prominence place, because of the possibility of utilization of wood that comes from planted forests. With the intention of diminution in the durability problems, when exposed to the weather effects, a solution presupposes the association of glulam beams with a reinforced concrete slab, in which the components are linked by means of flexible connections. This technique has been applied with results, especially due to the expressive increment in stiffness provided by the composition. However, in situations where high loads or great spans are found, the application of synthetic fibers reinforcements in the tension side of glulam beams improve this technique, being reflected in significant increments in the rupture forces. In this study it was evaluated, in experimental and numerical way, the structural behavior of glulam-concrete composite beams reinforced with glass fiber reinforced polymer (GFRP). In a first stage the connection elements were studied, being opted for steel hooks with 8 mm in diameter because of their exceptional behavior. Soon after, the composite beams were made with and without GFRP reinforcements and their tests showed average increment of 37% in modulus of rupture (MOR), when the composite beams were compared to glulam beams, both reinforced with GFRP. The decrease in the variability of results justifies the use of synthetic fibers reinforcements. Finally, an algorithm was proposed for the design of glulam-concrete composite beams reinforced with GFRP. So, when associated with the experimental and numerical evaluations that were carried out, this method allows enlarging the horizons of timber structures applications.

A primeira ferrovia no Brasil foi inaugurada em abril de 1854 pelo Barão de Mauá com 14,5 km de extensão. Atualmente o país possui 27980 km de ferrovias e esse modal tem participação em 25% na matriz brasileira de transporte de carga. Um dos componentes mais importantes da superestrutura ferroviária é o dormente, que pode ser fabricado utilizando-se diversos materiais como a tradicional madeira, que tem uso histórico e consagrado para esta aplicação estrutural, além do concreto e do aço, e mais recentemente, os compósitos poliméricos. As madeiras com maior tradição no uso em dormentes provêm de espécies nativas de alta densidade com consequente elevada resistência mecânica e durabilidade natural. Porém, devido às restrições impostas à extração destas espécies nativas, houve forte redução de sua oferta, sendo forçada sua substituição por madeira de florestas plantadas de eucalipto de alta densidade como E. citriodora, E. paniculata e E. tereticornis. Contudo, dormentes de diferentes espécies de eucalipto, pouco adequadas para esse uso, estão apresentando muitos problemas em via. Outra madeira de florestas plantadas muito utilizada no Brasil é o pinus e uma aplicação muito nobre para este tipo de madeira é a produção de elementos estruturais em Madeira Lamelada Colada (MLC). O objetivo do presente trabalho foi o estudo teórico e experimental de dormentes de MLC confeccionados com madeiras de Pinus spp. tratadas com CCA, coladas com adesivo poliuretano, e reforçados com tecido bidirecional de fibra de vidro. Para tanto, realizou-se um estudo teórico e experimental a partir de ensaios estáticos e dinâmicos tendo-se em vista a necessidade de utilização de novas espécies de madeira de reflorestamento com resistência adequada a tal finalidade. Os resultados obtidos nos ensaios realizados de acordo com a normalização vigente atestaram a viabilidade técnica da utilização de dormentes em MLC de Pinus spp. reforçados com fibra de vidro desde que sejam realizadas as classificações visual e mecânica das lamelas, para a obtenção das propriedades de resistência e rigidez necessárias. / Brazil\'s first railroad was inaugurated in April, 1854 by Barão de Mauá with 14.5 km of extension. Currently the country has 27980 km of railways, and this transportation modal has 25% participation in the Brazilian freight transport matrix. One of the most important elements of railway superstructure is the sleeper (or tie), which can be manufactured from several materials, such as the traditional wood, that has historical and well-established use for this structural application, as well as concrete, steel, and recently, polymer composites. The classic sleeper is made by timber from native species of high density with consequent high mechanical strength and natural durability. However, due to the restrictions imposed on the extraction of these native species, there was a strong reduction in their supply, being forced to replace them with timber from high density eucalyptus planted forests such as E. citriodora, E. paniculata and E. tereticornis. Therefore, sleepers from different eucalyptus species, that are not suitable for this use, are presenting many problems on railroad. Another wood from planted forests widely used in Brazil is the pinus, and a very noble application for this kind of wood is the production of structural elements in Glued Laminated Timber (Glulam). The aim of this work was the theoretical and experimental study based on static and dynamic tests of Glulam sleepers manufactured using Pinus spp. treated with CCA, glued with polyurethane adhesive, and reinforced with bidirectional fiberglass fabric. For that, a theoretical and experimental study was carried out from static and dynamic tests, considering the potential use of new reforestation species of wood with suitable strength to this purpose. The results show technical feasibility in the use of Glulam sleepers made with Pinus spp. reinforced with fiberglass provided that visual and mechanical classifications of the timber are realized, in order to obtain the required strength and stiffness properties.

O Brasil, um país de dimensões continentais e inúmeros rios em seu território, tem uma enorme carência de pontes para pequenos e médios vãos. Atualmente, a elevada produção de madeira de reflorestamento traz à engenharia uma opção de material renovável e ecologicamente correto para se utilizar em prol do ser humano nas obras de infraestrutura, mais especificamente na construção de pontes, uma vez que a madeira possui ótimo desempenho quando sujeita a cargas de curta duração. A utilização de Madeira Laminada Colada (MLC) permite a fabricação de peças de grandes dimensões, com excelente estabilidade, e com elevado controle de qualidade, proporcionando segurança e confiabilidade à estrutura. Este trabalho tem como objetivo o estudo teórico de pontes em vigas de MLC e tabuleiros em painéis de MLC utilizando procedimentos desenvolvidos por pesquisadores internacionalmente renomados e adequando estes procedimentos para as normas e condições brasileiras. Apresentam-se neste trabalho tabelas para pré-dimensionamento deste tipo de ponte para vãos de 8m a 20m para TB-30 e TB-45. Além disso, analisam-se numérica e experimentalmente os ganhos de rigidez e redução de deslocamentos relativos proporcionados pela utilização de vigas de enrijecimento, bem como a influência da seção destas vigas e a quantidade de parafusos utilizados para interligar ao tabuleiro. Por fim, apresentam-se algumas disposições construtivas não estruturais fundamentais para o bom funcionamento deste tipo de estrutura. / Brazil, a continental size country and with many rivers in its territory, has a huge necessity for short and medium spans bridges. Nowadays, the high production of reforestation wood allows to engineering an option of renewable material and ecologically correct to be used in favor to humans in infrastructure works, most specifically in bridges construction, once timber has a great performance in quick loads. The use of Glued-Laminated Timber (Glulam) enable the manufacture of large sizes members, with excellent stability, and a high control of quality in its production, providing a safety and reliability structure. This work aim the theoretical study of glulam stringers bridge and glulam panels deck using procedures developed by international researchers and adapting those procedures for Brazilian conditions and normalizations. Pre-design tables are presented in this work for 8m to 20m spans for TB-30 and TB-45. In addition to, analyses numerical and experimentally the gain of stiffness and the reduction of relative displacements between panels provided by the use of stiffener beams, besides the influence of those beams section size and number of bolts used for deck interconnection. Finally, it is presented some not structural constructive arrangements essential for good performance of this kind of structure.

Sammanfattning Intresset för höghuskonstruktioner i trä ökar allt mer runt om i världen. I Sverige ligger fokus på höghuskonstruktioner som utnyttjar intern vindstabilisering med skivor i KL-trä. I de högsta byggnaderna som använder trä som konstruktionsmaterial idag är det fackverk av limträ på byggnadernas ytterkant som når högst byggnadshöjder. Av den anledningen inleddes examensarbetet med målet att undersöka de dynamiska egenskaperna hos olika fackverkskonstruktioner med hänsyn till komforten för brukarna, något som vanligtvis är den mest kritiska analysen. För att bedöma komforten användes ISO 10137. Eftersom egenskaperna hos trä är sämre lämpade för höghuskonstruktioner jämfört med stål och betong valdes att förstärka byggnadens styvhet med en kärna i KL-trä runt hiss och trapphus. Den dynamiska analysen på fackverken har två delar, en av dem berör byggnadens dynamiska egenskaper och utförs i huvudsak i FEM-programmet Robot Structural Analysis och den andra delen handlar om byggnadens acceleration under inverkan av vind och består av handberäkningar. Båda områden inleddes med en litteraturstudie för att försäkra att resultatet i Robot Structural Analysis motsvarar beteendet hos en riktig byggnad och att sätta sig in i beräkningsgången av byggnadens acceleration, samt förstå bakgrunden till beräkningarna. Olika varianter av fyra sorters fackverk analyserades, X-fackverk, K-fackverk, diagridsystem och singulärt diagonala fackverk. Efter genomförda analyser framgick att diagridsystemet uppnådde den högsta byggnadshöjden på 87 m. X-fackverket klarar komfortkraven upp till 81 m och har mindre materialåtgång till fackverket jämfört med diagridsystemet. Jämfört med tidigare arbeten och konstruktioner klarar de undersökta konstruktionerna komfortfortkraven på högre höjder. Förklaringen till de höga konstruktionshöjderna kopplas till robustheten hos fackverken och kombinationen med KL-träkärnan. / Abstract There has been an awakening in high-rise buildings in timber around the world. In Sweden, the focus has been placed on high-rise building that utilize internal stabilisation against wind loading using panels made of cross laminated timber. However, the tallest timber buildings today utilize external stabilisation of glulam trusses. Therefore, the thesis work began with the purpose of examining the dynamical properties of different braced frame structures with regard to not cause discomfort to occupants, which is usually the most critical part of the building design. ISO 10137 was used to assess the comfort. Since the properties of timber are less well-suited for high-rise building constructions in comparison to steel and concrete, a decision was made to strengthen the rigidity of the building using a core made of cross laminated timber around the elevator and stairwell. The dynamic analysis of the braced frame structures has two parts. The first part concerns the building’s dynamic properties and is carried out mainly by using the FEM-software Robot Structural Analysis. The second part focuses on the acceleration of the building under the influence of wind and consists of hand calculations. Furthermore, the work in both areas began with a literature study in order to ensure that the result from Robot Structural Analysis corresponds with the behaviour of a real building and to familiarise oneself with the calculations regarding the acceleration of the building, as well as to understand the background of the calculations. Different variations of four types of braced frames structures were analysed: X-braced, K-braced, diagrid system and single-diagonal types. The analyses showed that the diagrid system reached highest with a building height of 87 m, while the X-braced type meets the comfort requirements up to 81 m and require less material compared to the diagrid system. As a result of the robustness of the trusses and the combination with the core made of cross laminated limber the examined constructions manage to meet the comfort requirements at higher heights than previous works and constructions.

The advancement in manufacturing technologies to produce high-performing engineered wood products (EWP) has allowed wood to be utilized beyond the traditional low-rise light-frame structures and to become a viable material option for much larger structures. Although glued-laminated timber (glulam) is included as a material option in the current blast code (CSA, 2012), its response to blast loading is not yet well documented. An experimental program investigating the behaviour of seventy glulam beams and columns was developed with focus on establishing the dynamic characteristics of glulam beams and columns with and without the effect of FRP reinforcement. A shock tube capable of simulating high strain rates similar to those experienced during blast was used. Thirty-eight beams with three different cross-sections were tested statically and dynamically to establish the high strain rate effects (dynamic increase factor). Six columns were also tested dynamically with axial load levels ranging from 15 to 75 % of the columns’ compression design capacity. Different retrofit configurations varying from simple tension reinforcement to U-shaped tension reinforcement with confinement using both unidirectional and bi-directional FRP were investigated on a total of twenty-six beams. A procedure capturing the strain-rate effects, variable axial load and FRP, was developed and found to be capable of predicting the flexural behaviour of the beams up to maximum resistance with reasonable accuracy when compared to experimentally obtained static and dynamic resistance curves. Implications on the design of both retrofitted and unretrofitted specimens are also discussed.

Cracks in wood are considered to be one of the major problems for products, which have been made from this material. Crack detection and its propagation methods should be revised and improved with application of modern techniques. Nowadays new measuring techniques like digital camera image processing, and 3-D laser scanning are available. This work describes computer aided in-field methods for registration cracks in wood, its propagation, and tracing dimensional stability of glued laminated beams. The benefits of different methods for supervision of wooden element as well as its limitations are discussed. / <p>Validerat; 20120608 (anonymous)</p>