Dissertations / Theses on the topic 'Dual Frame wall system'

Seismic design of standard structures is typically based on a force-based design approach. Over the years, this approach has proven to be robust and easy to apply by design engineers and – in combination with capacity design principles – it provided a good protection against premature structural failures. However, it is also known that the force-based design approach as it is implemented in the current generation of seismic design codes suffers from some shortcomings. One of these relates to the fact that the base shear is computed using a pre-defined force reduction factor, which is constant for a certain type of structural system. As a result of this, for the same design input, structures of the same type but different geometry are subjected to different ductility demands and show therefore a different performance during an earthquake. The objective of this research is to present an approach for computing force reduction factors using simple analytical models. These analytical models describe the deformed shape at yield and ultimate displacement of the structure and only require input data that are available when starting the design process, such as geometry and general material properties. The displacement profiles are obtained from section dimensions and section ductility capacities that can be estimated at the beginning of the design process. The so computed displacement ductility is taken as proxy of the force reduction factor. Such analytical models allow to link global to local ductility demands and therefore to compute an estimate of the force ductility reduction factors for wall and frame structures. Finally, this research develops an approach for frame-wall structures as combination of results obtained for wall and frame systems. The proposed method is applied to a set of frame-wall structures and validated by means of nonlinear time history analyses. Obtained results show that the proposed method yields a more accurate seismic performance than the current code design approach. The presented work therefore contributes to the development of revised force-based design guidelines for the next generation of seismic design codes.<br>La progettazione sismica di strutture è tipicamente basato su un approccio progettuale basato sulle forze. Nel corso degli anni, questo approccio ha dimostrato di essere robusto e facile da applicare dai progettisti e, in combinazione con il principio di gerarchia delle resistenze, fornisce una buona protezione contro i meccanismi di collasso fragili. Tuttavia, è anche noto che l'approccio di progettazione in forze così come attuato nell’odierna generazione di normative soffre di alcune carenze. Uno di questi riguarda il fatto che il tagliante alla base è calcolato utilizzando un fattore di struttura predefinito, cioè costante per tipo di sistema strutturale. Di conseguenza, per lo stesso input di progettazione, strutture dello stesso tipo ma diversa geometria sono sottoposti ad una diversa domanda di duttilità e mostrano quindi una diversa prestazione durante un evento sismico. L'obiettivo di questo studio è quello di presentare un approccio per il calcolo fattori di struttura utilizzando modelli analitici semplici. Questi modelli analitici descrivono la deformata a snervamento e spostamento ultimo della struttura e richiedono solo dati di input disponibili all’inizio del processo di progettazione, quali dati geometrici e proprietà dei materiali. La deformata della struttura ottenuta dalle dimensioni delle sezioni e la capacità in termini di duttilità sezionale possono essere stimati all'inizio della progettazione. La duttilità è alla base della formulazione del fattore di struttura come proposto dai modelli analitici presentati. Tali modelli analitici permettono di collegare le duttilità sezionali alla duttilità strutturale e quindi calcolare una stima del fattore di struttura per struttura a pareti e a telaio. Infine, si sviluppa un approccio per strutture duali di tipo telaio-parete come combinazione di risultati ottenuti per i sistemi singoli. Il metodo proposto è applicato ad un insieme di strutture duali e validato con analisi dinamiche non lineari. Si dimostra che il metodo proposto produce una più accurata prestazione sismica rispetto all'approccio progettuale delle normative odierne. Il lavoro presentato contribuisce pertanto allo sviluppo di nuove linee guida per la progettazione sismica nella prossima generazione di normative.

The purpose of this study is to investigate the influence of material and geometric nonlinearities occurring in beams, columns and walls of RC frame-wall structural systems when undergoing severe ground excitations. For this purpose, a low-rise RC building is considered with and without walls, and the joining beams and columns are designed with the strong-column weak-beam concept. The dimensions, material properties and the reinforcement amounts are calculated in accordance with the values suggested in design codes. Each structure is analyzed for various levels of applied vertical force and change in wall stiffness<br>where the effect of geometric nonlinearity is considered for each case. Force formulation frame elements with spreading inelasticity over the span are used for the modelling of each beam, column and wall. The coupling of the section forces is obtained by the fibre discretization of the section into several material points. Each section is divided into confined and unconfined regions and appropriate material properties are used for concrete and steel for cyclic loading. Both static pushover and dynamic analyses are performed in order to replicate the worst case scenario for a possible earthquake. From this study, it is concluded that the beams and columns of a frame-wall structural system should be designed carefully for load redistributions resulting from the yielding of the wall in the case of a strong earthquake, thus the design codes should address this situation for both in the retrofit of existing frame buildings with walls and in the construction of new frame-wall type buildings.

Master of Science<br>Department of Architectural Engineering and Construction Science<br>Kimberly W. Kramer<br>Dual Lateral Force Resisting Systems are currently required by code to include a Moment Resisting Frame capable of resisting at least 25% of the lateral loads. This thesis evaluates the seismic performance of a specific type of dual system: a Special Moment Resisting Frame-Special Concentric Brace Frame System (SMRF-SCBF) under three different force distributions. The three distributions were 80% - 20%, 75% - 25%, and 70% - 30% with the lesser force being allotted to the Special Moment Resisting Frame (SMRF) portion of the system. In order to evaluate the system, a parametric study was performed. The parametric study consisted of three SMRF-SCBF systems designed with different seismic force distributions. The aim of this study was to determine accuracy of the three different seismic force distributions. The accuracy was measured by comparing individual system models’ data and combined system models’ data. The data used for comparison included joint deflections (both horizontal and vertical), induced moments at moment connections, brace axial loads, column shears, and column base reactions. Two-dimensional models using the structural software RISA 3D were used to assist in designing the independent Seismic Force Resisting Systems. The designs of the frames were not finely tuned (smallest member size for strength), but were designed for drift (horizontal deflection) requirements and constructability issues. Connection designs were outside the scope of the study, except for constructability considerations – the SMRF and the SCBF did not have a common column; the frames were a bay apart connected with a link beam. The results indicated that a seismic force distribution of 75% to the SCBF and 25% to the SMRF most accurately predicts that frame’s behavior. A force distribution of 80% to the SCBF and 20% to the SMRF resulted in moderately accurate results as well. A vast opportunity for further research into this area of study exists. Alterations to the design process, consideration of wind loads, or additional force distributions are all recommended changes for further research into this topic.

In mid- to high-rise structures, dual systems (DS) enable a structural designer to satisfy the stringent drift limitations of current codes without compromising ductility. Currently, ASCE 7-05 permits a variety of structural systems to be used in combination as a dual system yet the design requirements are limited to the following statement: Moment frames must be capable of resisting 25% of the seismic forces while the moment frames and braced frames or shear walls must be capable of resisting the entire seismic forces in proportion to their relative rigidities. This thesis assesses the significance of the 25% design requirement for the secondary moment frames (SMF) in dual systems with consideration of current structural engineering practice. Three 20-story buckling-restrained braced frame (BRBF) dual system structures were designed with varying relative strengths between the braced and special moment frame systems. The SMF system wa designed for 15%, 25%, and 40% of seismic demands and the BRBF system design has been adjusted accordingly based on its relative stiffness with respect to the moment frame. These structures were examined with nonlinear static and nonlinear dynamic procedures with guidance from ASCE 41-06. The drift, displacement and ductility demands, and the base shear distribution results of this study show similar responses of the three prototype structures. These results indicate a secondary moment frame designed to less than 25% of seismic demands may be adequate for consideration as a dual system regardless of the 25% rule.

The diploma thesis deals with project documentation for the realization of a new fire station class C1 in Valašské Meziříčí. The building is is designet in two operating units - the garage part and the administrative part. The garage part has the necessary technical facilities and stockrooms. Over the garage there are rooms for firefighters performing the service during the night shift. The garage part follows the administrative part of the building, which has three above-ground floors. On the first floor there are offices of fire prevention, population protection and crisis management. On the second floor there are facilities for firefighters - a gym, a sauna, a day room and a classroom. The third above-ground floor is designed for the head of the territorial department, the chief of the fire station and the integrated rescue system office. The main entrance to the building is located in the administrative part of the western side at level 1NP. The structural system of the garage part consists of a prefabricated reinforced concrete frame. The administrative part is built in mansory system. The building is without cellar, roofed with flat roofs.

This Ph.D. dissertation is the result of a three-year research activity focused on structural and seismic engineering applied to innovative timber constructive systems. The main purpose is to give a contribution to international scientific research and current design practice about the seismic behaviour of timber shear-wall systems, which still represent an innovation in the construction industry and are being developed due to their favourable characteristics. An initial overview on the use of main timber structural systems in seismic-prone areas for low- and medium-rise buildings is provided, within the context of current European seismic code. The theme of the seismic design of timber shear-wall systems is discussed in the first part, giving close attention to linear and non-linear modelling criteria: various strategies are proposed and main characteristics are highlighted. Basic definitions and concepts proper of the seismic analysis of timber structures are provided. A particular attention is paid to the definition and application of the capacity design approach and the close link with the concept of behaviour factor is emphasized. Finally, the definition of behaviour factor, as product between an “intrinsic” capacity of the structure and a design over-strength value is proposed. This definition allows to characterize the structural systems with their proper dissipative capacity and to evaluate separately the safety reserve introduced by design. The second part analyses the structural behaviour of the cross-laminated timber (CLT) technology, which represents one of the most common timber structural systems. The concepts of ductility, dissipative capacity, regularity and irregularity applied to CLT system are provided. The seismic response and the dissipative capacity of this system are firstly evaluated via an experimentally based procedure. Then, the evaluation of its intrinsic dissipative capacity is determined via non-linear numerical modelling with the aim of studying the correlation with the construction variables. Results show that the construction design decisions affect the seismic response and dissipative capacity of buildings, as opposed to apply a single behaviour factor value to the whole CLT technology. A statistical analysis applied to numerical results allowed also to propose analytical formulations for the computation of the suitable behaviour factor value for regular buildings. Then, the same analyses carried out on in-elevation non-regular buildings returned a correction factor to account for the reduction in dissipative capacity due to irregularity. The application of the CLT technology to realize high-rise buildings is presented in the third part, analysing the behaviour of slender buildings with seismic resisting core and perimeter shear walls. The major limitations and drawbacks in realizing these structures in areas characterized by high seismic intensity and their implication in the design are reported. The final part presents three novel structural systems as alternative to more common technologies, as CLT or platform frame. These innovative systems are characterized mainly by a diffuse dissipative and deformation capacity when subjected to seismic loads, while in CLT system such capacity is concentrated in connection elements. This different response is studied via quasi-static tests and numerical simulations. In detail, two non-glued massive timber shear walls and a mixed steel-timber wall with an innovative bracing system are presented.<br>Questa tesi di dottorato è il risultato di tre anni di attività di ricerca in ambito ingegneristico strutturale applicato allo studio di sistemi costruttivi innovativi in legno. Il principale obiettivo è quello di fornire un contributo alla ricerca scientifica internazionale e ai metodi attuali di progettazione in merito alla risposta sismica di sistemi in legno a pareti sismo-resistenti, i quali rappresentano tutt’ora un’innovazione nel settore delle costruzioni e si stanno diffondendo grazie alle loro caratteristiche favorevoli. Una panoramica iniziale sull’utilizzo dei principali sistemi strutturali in legno in zone sismiche per la realizzazione di edifici bassi o di media altezza viene fornita e contestualizzata nella vigente normativa sismica europea. La prima parte della tesi affronta il tema della progettazione sismica di sistemi a pareti in legno, con particolare attenzione ai criteri di modellazione lineare e non lineare, proponendo diverse strategie ed evidenziandone le caratteristiche. In questa parte vengono forniti inoltre definizioni e concetti fondamentali propri dell’analisi sismica di strutture in legno. Un’attenzione particolare è riservata alla definizione e applicazione del “capacity design”, sottolineandone lo stretto legame con il concetto di fattore di struttura. Viene proposta infine una definizione del fattore di struttura come prodotto tra una parte intrinseca alla struttura e una sovraresistenza di progetto. Tale definizione permette di caratterizzare i sistemi strutturali con la propria capacità dissipativa e di valutare separatamente la riserva di sicurezza introdotta dalla progettazione. La seconda parte della tesi analizza il comportamento strutturale della tecnologia X-Lam (CLT), che rappresenta uno dei più comuni sistemi strutturali in legno. In questa parte vengono approfonditi i concetti di duttilità, capacità dissipativa, regolarità e irregolarità applicati al sistema X-Lam. La risposta sismica e la capacità dissipativa di questo sistema sono state preliminarmente valutate tramite una procedura analitico-sperimentale. Modelli numerici non-lineari hanno quindi permesso di valutarne la capacità dissipativa intrinseca in funzione delle variabili costruttive proprie del sistema. I risultati mostrano come le decisioni costruttive in fase di progettazione influenzino la risposta sismica dell’edificio; ciò è in contrasto all’applicazione di un unico valore del fattore di struttura per l’intera tecnologia X-Lam. Un’analisi statistica applicata a tali risultati numerici ha consentito di proporre formulazioni analitiche per il fattore di struttura per edifici regolari in funzione delle caratteristiche dell’edificio stesso. Infine, le stesse analisi condotte su edifici non regolari in altezza hanno fornito un coefficiente per tenere in conto della riduzione di capacità dissipativa a causa dell’irregolarità. Nella terza parte viene presentata un’applicazione della tecnologia X-Lam per costruire edifici alti, analizzando il comportamento di edifici snelli con nucleo sismo-resistente e pareti aggiuntive perimetrali. Vengono riportati inoltre le principali limitazioni e inconvenienti nel realizzare tali strutture in aree caratterizzate da elevata intensità sismica e le loro implicazioni nella progettazione. La parte finale descrive e analizza tre sistemi strutturali in legno innovativi, come alternative a tecnologie più comuni, quali X-Lam o platform-frame. Questi sistemi, soggetti ad azioni sismiche, sono caratterizzati da una capacità deformativa e dissipativa diffusa, al contrario del sistema X-Lam in cui tale capacità è concentrata principalmente negli elementi di connessione. Questa risposta differente è studiata attraverso test sperimentali quasi statici e simulazioni numeriche. In dettaglio, sono presentati e analizzati due sistemi a pareti massicce stratificate; realizzate senza l’uso di colla tra gli strati e una parete ibrida acciaio-legno con un sistema innovativo di controvento.

The aim of my diploma thesis is a design of fire station. The object is designed to be fire station type C and it is for fire brigade. The object is designed in Czech Budweis. The building has two above ground floor. The structural system of building is wall system and reinfroced concrete frame. The roof is warm flat roof. The facade is ventilated with cladding and sandwich facade panel. Drawing part processed in a computer program ArchiCAD.

I occupy with selected parts of the technological prepariation of building proces of a residential building in Vsetín in my diploma thesis. The building will be used for housing and retailing. The project is composed of eight building objects, while the main building structure is designed in detail. The subject of this thesis is the preparation of the technical report of the building, the treatise of the main technological stages, the design of the building site, the design of the main building machinery, the technology solutions including HSF and CTP, the construction budget, the time and financial planning of the construction and the specialization in the field of civil engineering.

Muchas ciudades del Perú se encuentran ubicadas en el cinturón de fuego del Pacífico, en consecuencia, existe una mayor probabilidad de ocurrencias de sismos que generen cuantiosas pérdidas de vida y grandes perjuicios económicos. Debido a este problema, la ingeniería civil está en la obligación de investigar nuevos diseños sísmicos más precisos, los cuales originaron diversos métodos que usan a los desplazamientos de la estructura como parámetro principal, ya que a través de los desplazamientos se pueden obtener los momentos y cortantes de la estructura. A este método se le conoce como Diseño Basado en Desplazamientos. El autor que le dio los lineamientos teóricos más amplios y consistentes es Priestley, con su propuesta llamada Diseño Directo Basado en Desplazamientos. Por otro lado, en la realidad peruana, las edificaciones con sistema estructura del pórtico de acero son atípicos en comparación con las de sistema dual de concreto armado. En consecuencia, se desaprovecha las propiedades de este material y de este sistema estructural, el cual se sumerge más en el rango inelástico que el concreto. La tesis analizará los resultados obtenidos del análisis sísmico de una estructura de sistema dual y otra de pórticos de acero, ambas con una misma configuración arquitectónica, bajo las metodologías de Diseño Directo Basado en Desplazamientos y de Diseño Basado en Fuerzas. Esto generará la comparación entre los sistemas estructurales bajo las metodologías mencionadas.<br>Many cities in Peru are located in the Pacific ring of fire, consequently, there is a greater probability of earthquakes that generate large losses of life and great economic damage. Due to this problem, civil engineering is obliged to investigate new more accurate seismic designs, which originated several methods that use the displacements of the structure as the main parameter, since through the displacements the moments and shear of the structure can be obtained. This method is known as Displacement Based Design. The author who gave the broadest and most consistent theoretical guidelines is Priestley, with his proposal called Direct Displacement Based Design. On the other hand, in the Peruvian reality, steel frames buildings system are atypical compared to those of the dual wall-frame with reinforced concrete system. Consequently, the properties of this material and this structural system are wasted, which is more immersed in the inelastic range than concrete. The thesis will analyze the results obtained from the seismic analysis of a dual wall-frame building and another of steel frames, both with the same architectural configuration, under the Direct Displacement Based Design method and the Design Based Force method, which is the method used in most standards. The thesis will generate the comparison between the structural systems under the mentioned methodologies.<br>Tesis

This diploma thesis deals with the design of a new sports center, which is situated in the cadastral unit of the village Všechovice 787086 (district of Přerov), on the plot number 163/1. The land is a planar character. It is a three floor building with two above-ground and partial basement. The construction is a square ground plan. The building is based on the strips foundation and foundation pads. The wall structural system consists of sandstone km beta sendwix blocks. The frame structural system is made up of reinforced concrete columns and beams, with the brickwork made of ytong classics. The external walls are insulated with a mineral wool insulation etics contact system. Ceiling structures are made of reinforced concrete slabs and wooden ceiling beams. The building is roofed with 3% flat roofs and part of the multipurpose hall is roofed with a curved, rolled roof. The diploma thesis is performed as a design documentation for the building process.

The assignment of the diploma thesis follows the pre-diploma project of an urbanistic design - New South District and its Connection to Svratka. The subject of the thesis is a design of the apartment building on the riverside of Svratka. The thesis has a form of architectonic study. The architectural design is interconnected with surrounding built-up area and preserves the existing height level. It also respects the definened riverside. The construction has a shape of the letter "U" opening towards the river. The shift of the north "wing" of the building creats widened "inner block". It offers diverse views on the river and accentuates an "incorporation" of the river to inner block. The residential building has six floors and two underground parking floors. It is devided into 7 units with separate entrances. The proposed part of the building is located directly on the riverbank. It includes 16 housing units and one leasable space.

Diploma thesis deals with the design of the multifunctional building located between Havlickova and F. Vogner streets in relation to the existing building in Litomyšl. Building plot is slightly sloping, at the rear goes into greater inclination. The building has four aboveground floors and one underground floor. The building includes services, located in ground floor, administrative premises decomposing in the second and third floor and apartments on the top floor. In the basement are located parking spaces. Supporting skeleton of the building is a cast-in-place concrete frame. Roofs are designed as a flat single shell. In part of roof over third floor is a green roof. The building is founded on piles. Due to the occurrence of water pressure is building an extra solved waterproofing system with checks and activation. The work includes text messages, drawings for building construction, fire safety design, construction and physical assessment of building structures and specialization from concrete structures.

The final thesis deals with design of new administrative object. The administrative object is located in edge part of Znojmo city. The building is situated in built-up area, which is used for housing and services. The building is accessible as a detached house on a slightly sloping territory. It is a four-storey house with a cellar, terminated by a warm flat roof, which has three-storey and basement. On the above ground floors are located offices and their associated spaces, staff facilities and toilets. On the third floor there is a terrace for employees’ stay in the summer months. On the third floor there is a collective garage with twenty parking spaces too. The individual floors are accessed via the main staircase and elevator. The building is designed as reinforced precast concreate frame and is based on prefabricated reinforced concrete foundation pads. The infill and internal wall are designed from the Porotherm building system.

The aim of this master thesis is proposal of a sport center building. The proposal consists of design of a detached building with room for climbing gym, sauna, massage room and also space for fitness, spinning and yoga. A bar with area for relaxing is a part of the building as well. The sport center has two floors and no basement. Due to the climbing gym, the second floor does not cover all disposition of the second floor. The support system of the building is skeletal. Part of the building´s roof is supported by steel truss frames with purlins, another part with solid panel trusses with purlins. The cieling is made of holoribs and reinforced concrete. The building is covered by single layer roof and has ventilated facade.

The subject of this thesis is to create a project documentation of the design of new construction of fire station in Šumperk. The fire station is designed according to ČSN 73 5710 as a C type station that will be used by professional fire brigade of Olomouc district. The object is structurally divided into two parts - a masonry building, and a reinforced concrete frame. The administrative part of the building together with the base of the fire brigade, technical room, and a fire tower are designed as a masonry building made of Ytong cellular concrete units. One of the parts is designed as a two-level object, while the technical room and the fire tower are designed as a sigle-level object. The circumferential masonry is insulated by contact thermal insulation system. The floor construction is made of Spiroll prestressed floor slabs. The roof is designed as a warm flat roof. The garage is a single-level building with built-in structure of storerooms in part of the garage. The precast reinforced concrete frame is set on foundation pads and foundation sills. The horizontal and vertical supporting structure consists of reinforced concrete parts – columns, Spiroll floor slabs, floor girders, sway frames, purlins and small purlins. The whole object is covered by a warm flat roof. The external cladding consists of PUR isolating sanwich panels.

This diploma thesis is being solved for documentation of building in the stage of execution. The building is designed as a showroom with car repair shop. The building site is located in the land registry of Ostrava – Vítkovice. Project documentation is designed accordingly to the valid Czech Republic’s laws, bills and building standards. The building is divided into two objects the first one is showroom with administration and the second one is the car repair shop with washing room and restrooms. These two objects are structurally and operationally connected. The largest plan dimensions are 68,56 x 38,36 m. The building is designed as a reinforced concrete frame in the administrative part and a reinforced concrete wall system in the car repair part. The roof is in both cases realized by using steel trusses. The reinforced concrete frame is lined with aerated concrete masonry. In the roof part it is cladded with sandwich steel panels. The building is founded on reinforced concrete foundation pads with combination of strip foundations. The car repair shop is designed as one floor building, whereas the administrative part is designed as two floor.

The aim of the project is a new building of a sport and wellness center in the cadastral area Brno-Židenice, South Moravian Region. Sport and wellness center is designed as a detached building with two floors and basement with a flat single skin vegetation roof. In the 1st floor there is a reception, cafe, children's play area, central changing rooms and a technical facilities. In the 2nd floor is a fitness center, solarium, massage rooms and sports nutrition and diagnostics. In the basement is a wellness center, facilities for employees and lasergame arena. The main structural system of the building consists of reinforced concrete columns and reinforced concrete slabs. The facade is designed as a contact thermal insulation system and glazed curtain wall.

Master’s thesis deals with complete project documentation of newly built object of library and mediatheque located on the site in České Budějovice. It is a three-storey building divided into three parts, one-storey, two-storey and three-storey. It is partly basement. The underground part is devoted to main storage spaces of library services, management offices and social facilities for staff (toilets, changing rooms, washrooms). This part of the building has own entrance for employees. In the 1st floor is located the main library area along with exhibition spaces and the main entrance for visitors with self service cloakroom. In the 2nd floor are designed library spaces for visually impaired persons with fund of audio books, CDs and DVDs, a lecture hall with a projector and own kitchen and space for reading magazines and periodicals. From this floor is possible access to the outdoor terrace, which has own terrace furniture store nearby. In the 3rd floor is located a literary café with its own facilities. In each floor are also designed sanitary facilities for use by persons with limited ability of movement and orientation. All floors are connected by stairs and passenger lifts. In terms of construction, the building is designed as a frame, in the underground parts made of reinforced concrete, the overhead of glued laminated timber elements. The ceiling structure designed over the underground floor is monolithic reinforced concrete slab. The ceilings in the upper part are designed as a wooden beamed made of the glued laminated timber elements. The building has a pent roof created by wooden trusses assembled with punched metal plate fasteners. The foundations are designed as belts and footings. The study, detailed documentation, thermal-technical evaluation of selected structures and fire safety of the building are processed. For processing of the thesis were used software AutoCAD 2010, Teplo 2011, Area 2011, Ztráty 2011 and Fire NX 802 PRO.

Il lavoro in questa tesi riguarda l’estensione, il miglioramento e la validazione della metodologia Simple Lateral Mechanism Analysis (SLaMA) per la valutazione sismica di strutture in CA. Raccomandato nelle linee guida neozelandesi del 2017 relative alla valutazione sismica, NZSEE (2017), SLaMA é un metodo di analisi non-lineare che permette di avere una stima della capacitá di strutture esistenti ed é valido per telai, pareti o sistemi misti telaio/parete. L’idea di base é procedere “dal locale al globale”, partendo dal comportamento di componenti singoli, estendendolo a specifici sottoschemi ed infine giungendo al comportamento globale dell’edificio. É anche possibile considerare gli effetti torsionali in campo non-lineare. Dato che il metodo si basa su ipotesi semplificate, non é necessario ricorrere a modelli numerici e i calcoli possono essere fatti “a mano (i.e. utilizzando un foglio elettronico). La prima parte di questo lavoro di ricerca riguarda i sistemi a telaio nudo, identificando aree di miglioramento della procedura SLaMA esistente e proponendo una procedura estesa e migliorata. Essa é stata validata attraverso la sua applicazione a 40 casi studio ideali e il confronto con i risultati di analisi numeriche raffinate (FEM Pushover). I risultati indicano che la procedura SLaMA modificata permette di identificare accuratamente il meccanismo plastico del telaio, considerando l’effettiva gerarchia delle resistenze dei suoi componenti, e di calcolarne la curva di capacitá con errori accettabili per i suoi parametri più significativi. La parte successiva del lavoro riguarda lo sviluppo di una nuova procedura SLaMA, non presente in NZSEE (2017), per sistemi a telaio tamponato, che rappresentano una cospicua parte del patrimonio edilizio, soprattutto in Europa. La nuova metodologia si basa su una procedura meccanica, proposta in questo lavoro, per disaccoppiare i contributi al taglio alla base relativi al telaio e alle tamponature, per un qualunque valore dello spostamento globale. La procedura di disaggregazione é applicabile a prescindere dalla distribuzione delle tamponature e della curva caratteristica dei puntoni equivalenti. Puó essere inoltre applicata per la post-processione dei risultati di analisi Pushover o Time History di telai tamponati. In analogia a quanto fatto per i telai nudi la procedura SLaMA é stata validata tramite confronto con i risultati di analisi Pushover per 72 casi studio. Sono stati inoltre considerati i sistemi resistenti misti telaio/parete con l’obiettivo di proporre una nuova procedura SLaMA che considerasse esplicitamente l’interazione tra la parte a telaio con quella a parete, includendo il calcolo delle forze da essi scambiate e le eventuali coppie concentrate dovute alla presenza di travi di collegamento. Con la nuova procedura SLaMA é possibile stimare il comportamento dei sistemi duali con grande accuratezza, come dimostrato da una vasta analisi parametrica (SLaMA vs Pushover) che coinvolge 24 casi studio. L’ultima parte del lavoro riguarda la valutazione sismica di un edificio realmente esistito e che ha subito notevoli danni durante la sequenza sismica di Christchurch (Nuova Zelanda) tra il 2010 e il 2011. Lo “score sismico” (capacitá fratto domanda) é stato indipendentemente valutato con diversi metodi di analisi: Lineare Statica, Lineare Dinamica, Non-Lineare Statica (Pushover e SLaMA), Non-Lineare Dinamica. In primis questo confronto incrociato dimostra l’affidabilitá del metodo SLaMA nella valutazione di casi reali complessi. Questo studio dimostra inoltre come le informazioni ottenute utilizzando SLaMA possano essere efficacemente usate per calibrare i parametri fondamentali necessari per gli altri metodi di analisi, o interpretarne i risultati. Sebbene alcuni passi della procedura possono essere calibrati in maniera piú raffinata grazie a sviluppi futuri si puó sicuramente affermare che SLaMA sia un metodo di analisi robusto. Esso é in grado di fornire al tecnico valutatore gli strumenti per comprendere i dettagli del comportamento di un edificio usando esclusivamente calcoli fatti a mano (eventualmente implementati in un semplice foglio elettronico).<br>This dissertation is focused on the extension, refinement and validation of the Simple Lateral Mechanism Analysis (SLaMA) method for the seismic assessment of RC buildings. Suggested in the 2017 New Zealand guidelines for seismic assessment, NZSEE (2017), SLaMA is an analytical non-linear analysis technique that provides a first estimation of the global capacity curve of the primary lateral-resisting systems in RC buildings, including bare frames, cantilever walls and dual wall/frame systems. The basic idea is to progress “from local to global”, extending the local behaviour of the structural members to selected sub-schemes, and finally to the global non-linear response of the building. Inelastic torsional effects are also included. Since simplified assumptions are made, no numerical computer model is needed and hence all the calculations can be performed “by hand” (i.e. implemented in an electronic spreadsheet). The first part of this investigation is related to bare frame Lateral Resisting Systems, with the identification of potential areas of improvement for the existing SLaMA procedure and the proposal of an extended/refined one. The refined procedure for bare frames is validated through the application to a set of 40 ideal case studies and the comparison with refined numerical analyses (FEM Pushover). The results show that the refined SLaMA procedure allows to accurately identify the expected plastic mechanism of the frame, also considering the actual hierarchy of strength of its members, and to properly estimate its non-linear capacity curve with acceptable errors on the most meaningful parameters. The subsequent part of the investigation involves the development of a novel SLaMA method to evaluate the capacity curve of masonry-infilled frames systems, which represent a large portion of the building portfolio, especially in Europe. The incorporation of the contribution of the infills is completely absent in the NZSEE (2017) SLaMA framework. The methodology is based on a proposed mechanically-based procedure to decouple the frame and infills contributions to the overturning moment (and hence base shear) capacity for any value of the global displacement. The decoupling procedure is applicable regardless of the distribution of the infills and of the non-linear Axial load-Axial strain of the equivalent struts. It can be applied to post-process the results of Pushover or Time History analyses of different types of infilled frames (material-wise). Similarly to what done for bare frames, an extensive SLaMA vs numerical Pushover comparison, for a set of 72 ideal case studies, is used to validate the proposed SLaMA procedure. Part of the investigation is dedicated to dual wall/frame system structures, proposing a novel SLaMA procedure in which the coupled behaviour of the frame and wall(s) components is expressly considered, including the calculation of the exchanged forces and the concentrated moment couples due to the possible presence of link beams. By using the new SLaMA procedure it is possible to capture the non-linear behaviour of the dual system with extreme accuracy, as demonstrated with an extensive SLaMA vs numerical Pushover parametric analysis comprising 24 ideal case studies. The last step of the work is the seismic assessment of a real case study building, severely damage in the Christchurch (New Zealand) sequence of earthquakes in 2010-2011. Different analysis techniques are used to independently derive the “seismic score” of the building (capacity over demand), including: Linear Static, Linear Dynamic, Non-Linear Static (numerical Pushover and SLaMA) and Non-Linear Dynamic analyses. Firstly, this demonstrates the reliability of the SLaMA method in assessing real, complex cases by means of a cross-validation. Moreover, and perhaps more importantly, it is deemed that this comparative study demonstrates how the insights gained by using SLaMA can be used to calibrate important parameters needed when adopting other analysis techniques, or interpreting their results. Additional investigations might help in fine-tuning some of its steps but, overall, it is deemed that SLaMA constitutes a robust analysis technique that allows the assessor to really understand the behaviour of an RC building only using hand calculations, possibly implemented in a simple spreadsheet.

A considerable amount of research has focused on load-sharing and system effects in repetitive-member wood floor systems subject to transverse loading. However, relatively few studies have been conducted to investigate load-sharing and system effects in repetitive-member wall systems which may be subject to combined transverse and gravity (vertical) loading, and which may have different boundary conditions from floors. This research investigates load-sharing and system effects in light-frame wood wall systems and seeks to develop repetitive-member system factors for codified design that rationally account for load sharing and other system effects. These factors are intended for use in the design of individual wall members, much as repetitive-member factors are used in the design of parallel-member floor and roof systems. As part of this research, an analytical model was developed to account for partial composite action, two-way action, and openings in the wall system. The model was validated using experimental test results and was shown to be able to predict reasonably well the response of light-frame wall systems. The model was then incorporated into a Monte Carlo simulation to perform reliability analyses of light-frame wall systems. Since the structural model is complex, and including a time-history analysis within the time-dependent simulation was not computationally practical, the load combination issue was considered separately from the reliability analysis. Sensitivity studies were conducted to investigate how different system parameters affect strength and reliability of light-frame wall systems. The reliability of light-frame wall systems was next evaluated using a portfolio of representative light-frame wall systems designed according to current code provisions. This portfolio approach was also used in evaluating system factors for light-frame wall systems. Thus, two different approaches (a reliability-based approach and a strength-ratio approach) were considered for developing system factors for member-design to account for load sharing, partial composite action and other system effects. Using the strength-ratio approach, a new framework for system factors (i.e., partial system factors) is suggested in which the effects of partial composite action, load sharing, load redistribution and system size (number of members) are treated separately.<br>Graduation date: 2003

In the present scenario, the buildings being constructed in India are increasing in Heights. The metropolitans are witnessing higher and higher towers with each coming day. Though, the average height of these new buildings may be ranging between 25-30 stories, there are a number of structures which are fairly high and need better structural understanding to give economical and safer designs. Majority of structures in India are based on the traditional Moment resisting frame concept in which the beams and columns cater to the gravity loads as well as the lateral loads by virtue of its moment resisting capacity. But this system is not efficient for buildings with heights greater than 15 stories. Hence, a different concept of shear wall is being widely used as a suitable alternative. With shear walls lateral force resisting capacity of buildings is improved drastically. With the use of shear wall structural system together with special moment resisting frame or with ordinary moment resisting frame the height of building has increased to 30 stories. But, in order to achieve economy, aesthetics and architectural requirements a new structural system which comprises of only slab and column mechanism is being looked upon. This structural system is called as flat plate system in which the thickness of slab remains constant and columns rest directly on the slabs without any drops or beams. This system not only has an aesthetic edge over traditional beam-column system or flat slab system, but also proves to be economical because of lower construction time and lesser storey height. In this paper we have studied the behavior of flat plate system with increase in height. The study comprises of buildings with and without shear wall systems. The problem areas of using flat plate system have been discussed in this paper, which primarily comprise of unbalanced moment transfer of moment from column to slab, and lesser stiffness of the building as a whole to resist lateral loads. The behavior of flat plate system has also been compared with the traditional beam column moment resisting frame system and their differences have been studied. Analysis of Flat plate under gravity loading has also been performed in computer software and is compared with the direct design method of IS 456. Future scope of this paper includes economical comparison of the moment resisting frame structure and flat plate structure.