Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Civil Engineering; and, (M.S.)--Massachusetts Institute of Technology, Dept. of Architecture, 1981. / MICROFICHE COPY AVAILABLE IN ARCHIVES AND ENGINEERING. / Bibliography: p. 175-178. / by Joseph Gilmary Burns. / M.S.

京都大学 / 0048 / 新制・課程博士 / 博士(工学) / 甲第21364号 / 工博第4523号 / 新制||工||1704(附属図書館) / 京都大学大学院工学研究科建築学専攻 / (主査)教授 西山 峰広, 教授 竹脇 出, 准教授 倉田 真宏 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DFAM

Byggmaterialmarknaden i Sverige uppfattas idag som oligopolisk där ett fåtal företag dominerar en stor del av marknaden. Nya inköpsvägar för material kan öka konkurrensen och förändra villkor för aktörer i branschen. Flera utredningar menar på att import är en sådan inköpsväg som kan förändra den nuvarande prisstrukturen. Men för företag som ser import som en möjlighet kommer även ny problematik som måste hanteras. Företaget Midroc har ett stort intresse i att utreda möjligheten för att köpa in färdiga betongstommar från andra sidan Östersjön. Rapporten syftar främst till att undersöka och utvärdera olika leverantörer av betongelement i utlandet och på så sätt samtidigt undersöka möjligheterna för import. Genom intervjuer, litteraturstudier och enkäter till inköpare samt lokala leverantörer har kritiska faktorer tagits fram. Dessa innefattar bland annat teknisk standard, garantier, transport och risker. Det kom fram tidigt i studien att det finns en diskrepans mellan de tekniska standarder som tillämpas i Sverige jämfört med andra länder. Detta måste naturligtvis tas i särskild hänsyn så att produkterna som köps in är godkända att användas i Sverige. Ett sätt att säkerställa detta är att köpa betongprodukter som är certifierade med BBC-märket. Ett formulär med frågor upprättades, frågorna var menade att ge en inblick i vad företagen erbjuder och hur de arbetar. Prisfrågor har inte tagits med då det var omständigheterna kring ett internationellt inköp som var av störst intresse. Det har dock kommit fram att priset för betongstommar i Baltikum kan vara 20-30 % lägre än de nationella priserna. Företag i Polen och Baltikum kontaktades via telefon och på mejl, dessa fick möjlighet att svara på frågeformuläret. Företagen som svarade hade aktuella projekt i Sverige och hade fortsatt intresse av att utveckla sin marknad. Utifrån svaren som gavs har en leverantörsvärdering tagits fram för att värdera de leverantörer som passar företaget. Syftet var att försöka avgöra om det var lämpligt att gå vidare med leverantören. Det faktum att alla företagen redovisade ett pågående samarbete med flera byggföretag i Sverige, att flera av företagen är både vana och villiga att arbeta enligt allmänna bestämmelser, att de erbjuder helhetslösningar osv. visar på att möjligheterna för lyckad import är goda. / The construction material market in Sweden is considered today to be oligopolistic where few companies dominate the market. New ways of procuring materials could increase the competition and change the terms for all the actors. Studies have shown that import is one of those new ways of procuring materials, thus altering the current price structure. But companies that consider importing materials will face problems that need solving. The company Midroc has shown great interest in investigating the possibility for purchasing precast concrete structural elements from overseas. The main purpose of this report is to investigate the possibilities of importing and evaluating potential suppliers. Through interviews, literature and inquiries to sales managers and local suppliers, important factors have been identified, such as standards, warranties, transportation and financial risk. A significant finding was that there are technical standards that differ between countries which can impede import. One way to surpass this is to look for concrete products which are certified with the BBC mark. A questionnaire was made which was meant to give useful information about what the company offers and how they work. Price was not included due to the fact that the main interest was the circumstances around an international purchase. However, it has emerged that concrete structural elements in the Baltic States could be 20-30 % cheaper than Swedish products. Suppliers in Poland and the Baltic states were phoned and e-mailed. The suppliers that answered were all currently working in Sweden and interested in increasing their export. A supplier assessment was made which is based on the answers. The fact that all companies were currently cooperating with construction companies in Sweden, show that they are familiar with Swedish regulations and often are able to offer an overall solution. This indicates that the possibilities of importing precast concrete elements to Sweden are good.

Thesis (MScEng)--Stellenbosch University, 2013. / ENGLISH ABSTRACT: This thesis is a study in the use of precast modular construction as an alternative to current methods of school construction in South Africa. Precast Modular Construction is a concept which utilises the principles of prefabrication and precast concrete. Concrete components, be they beams, columns, slabs or full volumetric modules, are manufactured either off-site in factories or in on-site facilities. These components are then assembled on-site to form the structural envelope of a building. This approach contains many inherent advantages: Time is saved due to on-site and off-site work happening concurrently and hence earlier building occupancy results which directly translates to cost reparation; quality is improved due to most of the work being carried out in a controlled factory environment; and health and safety is heightened. However, when viewed from a South African perspective, the fact that less work is done on-site indirectly implicates job loss, a serious issue in the country. Furthermore, implementing a prefabricated approach in the construction of South African schools requires a complete restructuring of the Department of Public Works’ current procurement approach. Prefabrication requires maximum integration between all parties to a project so that design and constructability issues can be addressed at an early stage. The design-build contract strategy is found to be the most integrated approach and allows for optimal collaboration between all project members. However, to only change the procurement route would not suffice as a complete solution. A broader approach is required which addresses issues prevalent in South Africa. These issues include job creation and the establishment of a sustainable and knowledgeable industry. Concepts such as standardisation and strategic partnering, in response, satisfy the need of the manufacturer - for economies of scale, and the employee - for creation of secure working environments. Verification is obtained from all of the aforementioned to propose that the optimal solution to successfully implement Precast Modular Construction for schools in South Africa would be to implement a design-build procurement approach, whereby a single design-build contractor is awarded by the Department of Public Works a contract, via competitive tendering, for the construction of a predetermined number of schools, preferably exceeding 3, over a given contract period using a standardised design and utilising customisable standardised prefabricated precast construction systems, i.e. Precast Modular Construction. This proposal will theoretically result, amongst other things, in the following: - Precast manufacturers will have a confirmed number of orders for products, and can hence be assured of a constant flow of income. This translates directly to an increase in both employment and job security at the manufacturing plant. - The economies of scale principle is satisfied and prefabricated components can therefore be manufactured or ‘mass customised’ in the most feasible way possible. - The design-build contractor will be guaranteed employment for a given period, once again providing job security for its employees, of which the number can also potentially increase. - The design-build contractor carries with it experience and lessons learned from each successfully completed project on to the next, and so becomes more proficient, resulting in better, higher quality schools delivered in shorter periods and with increased efficiency. It is recognised that the proposal is untested in practise but in a socio-economic situation such as South Africa, where large numbers of schools are required quickly, the above proposal makes sense. To additionally develop this hypothesis, further research is required in the fields of design-build procurement and strategic partnering. / AFRIKAANSE OPSOMMING: Hierdie tesis is 'n studie in die gebruik van modulêre voorafvervaardigte beton konstruksie as 'n alternatief vir die huidige metodes van skool konstruksie in Suid-Afrika. Modulêre voorafvervaardigte beton konstruksie bevat baie inherente voordele. Tyd word bespaar as gevolg van werk wat gelyktydig op en van die terrein af gebeur. Dus word die gebou vroeër betrek wat direk lei tot kostebesparings. Kwaliteit verbeter as gevolg van meeste van die werk wat in 'n beheerde fabriek omgewing uitgevoer word en as sulks lei tot beter gesondheid en veiligheid van werkers. Egter, vanuit 'n Suid-Afrikaanse perspektief impliseer die feit dat daar minder werk op die terrein gedoen word indirek werksverlies, 'n ernstige probleem in die land. Die implementering van 'n voorafvervaardigde benadering tot die bou van skole in Suid-Afrika vereis verder 'n volledige herstrukturering van die huidige verskaffing model. Voorafvervaardiging vereis maksimum integrasie tussen alle partye sodat projek ontwerp en boubaarheid op 'n vroeë stadium aangespreek kan word. Die ontwerp-bou kontrak strategie is die mees geïntegreerde benadering en laat toe vir optimale samewerking tussen alle projek lede. Om egter net die verskaffing roete te verander, sou nie voldoen as 'n enkele oplossing nie. 'n Breër benadering word vereis wat kwessies algemeen in Suid-Afrika aanspreek. Hierdie kwessies sluit in werkskepping en die vestiging van 'n volhoubare en kundige industrie. Konsepte soos standaardisering en strategiese vennootskap, as oplossings, voldoen aan die behoeftes van die vervaardiger - vir 'n ekonomieë van skaal, en die werknemer - vir die skepping van 'n versekerde werksomgewing. Die voorafgaande bevestig dat die optimale oplossing vir suksesvolle implementering van Beton Modulêre Konstruksie vir skole in Suid-Afrika sou wees om 'n ontwerp-bou verskaffingsprosedure te volg. Hierdeur kan 'n kontrak aan 'n enkele ontwerp-bou kontrakteur deur die Departement van Openbare Werke toegeken word, deur middel van ‘n mededingende tender proses. Daar word voorgestel dat die projek, vir die konstruksie van 'n voorafbepaalde aantal skole behoort te wees, verkieslik meer as 3, oor 'n bepaalde kontrak tydperk met behulp van 'n gestandaardiseerde ontwerp. Voorts word daar voorgestel om gebruik te maak van aanpasbare gestandaardiseerde voorafvervaardigde beton konstruksie stelsels, dws Beton Modulêre Konstruksie. Hierdie voorstel sal teoreties, onder andere, die volgende gevolge hê: - Beton vervaardigers sal 'n bevestigde aantal bestellings vir produkte hê, en kan dus verseker wees van 'n konstante vloei van inkomste. Dit lei direk tot 'n toename in indiensneming en werksekerheid by die fabriek. - Die ekonomieë van skaal beginsel is bevredig en voorafvervaardigde komponente kan dus vervaardig word in die mees haalbare manier moontlik. - Die ontwerp-bou kontrakteur is gewaarborg van indiensneming vir 'n gegewe tydperk, as sulks ook die verskaffing van werksekerheid vir sy werknemers, waarvan die aantal moontlik ook kan vermeerder. - Die ontwerp-bou kontrakteur neem ondervinding en lesse wat geleer is uit elke suksesvolle voltooide projek saam na die volgende een, en raak dus meer bedrewe, wat lei tot beter, hoër gehalte skole gelewer in korter tydperke en met toenemende doeltreffendheid. Die voorstel is egter ongetoets in die praktyk, maar in 'n sosio-ekonomiese situasie soos die van Suid-Afrika, waar 'n groot aantal skole vinnig benodig word, maak die bogenoemde voorstel sin. Om hierdie hipotese te ontwikkel, is verdere navorsing nodig in die gebied van ontwerp-bou verskaffing en strategiese vennootskappe.

Thesis (MEng)--Stellenbosch University, 2014. / ENGLISH ABSTRACT: Construction of structural concrete frames may take place by using either cast in-situ or precast methods. With the cast in-situ method, these elements are constructed on the construction site as needed. Precast construction on the other hand is more resembles a line. The elements are constructed in a precast yard in a systematic fashion and once completed, they are taken to the construction site where they are to be erected. This study identifies the aspects and attributes which influence the quality of concrete during the construction phase of these two construction methods. The study is independent from the conceptual or design phase. Information regarding these aspects and attributes were obtained from literature and from contractors in industry through interviews and site visits. The literature review also focuses on quality management techniques and factors that influence quality in the construction environment. The information obtained from the site visits and literature was used to design a survey which was sent out to a number of respondents. A comparison between in-situ and precast construction was made based on the results of the survey. The synthesis of the research findings can be used by project teams to help them decide on the choice between in-situ and precast construction. It was found that precast construction is better for durability, and fitness for purpose is less complex for the in-situ solution. Recommendations for future studies are provided at the end of the document. / AFRIKAANSE OPSOMMING: Konstruksie van beton struktuurrame kan plaasvind deur die gebruik van in-situ of voorafvervaardigde metodes. Met die in-situ metode, word hierdie elemente op die terrein gebou soos benodig. Tydens voorafvervaardigde konstruksie aan die ander kant is die konstruksie soortgelyk aan 'n produksielyn. Die elemente word gegiet in 'n voorafvervaardingsterrein in 'n sistematiese wyse, en sodra dit voltooi is, word dit na die konstruksie terrein geneem waar dit opgerig word. Hierdie studie identifiseer die aspekte en eienskappe wat 'n invloed op die kwaliteit van beton het tydens die konstruksiefase van hierdie twee konstruksie metodes. Die studie is onafhanklike van die konseptuele of ontwerp fases. Inligting rakende hierdie aspekte en eienskappe is verkry uit die literatuur en van kontrakteurs in die bedryf deur middel van onderhoude en besoeke. Die literatuur fokus ook op die gehalte, bestuurs-tegnieke en faktore van gehalte in die bou-omgewing. Die inligting is verkry deur ‘n vraelys wat aan 'n aantal respondente gestuur is. 'n Vergelyking tussen in-situ en voorafvervaardigde konstruksie is vervolgens gemaak op grond van die resultate van die opname. Die sintese van die bevindinge kan gebruik word deur projek spanne om hulle te help besluit oor die keuse tussen in-situ en voorafvervaardigde konstruksie. Die resultate dui daarop dat voorafvervaardigde konstruksie beter is vir duursaamheid, maar passing op terrein is minder kompleks vir die in-situ oplossing. Aanbevelings vir toekomstige ondersoeke word aan die einde van die studie gemaak.

O presente trabalho trata do estudo do comportamento de chumbadores grauteados inseridos em concreto com fibras de aço em ligações viga-pilar de estruturas de concreto pré-moldado. Este estudo é importante para se entender e poder quantificar a influência da rigidez deste componente no comportamento de ligações semirrígidas de estruturas de concreto pré-moldado. O objetivo do trabalho é estudar o mecanismo do chumbador no concreto com fibras de aço em ensaios específicos e avaliar também o comportamento de uma ligação viga-pilar de concreto pré-moldado utilizando estas fibras no consolo e no dente da viga. Nesta pesquisa foi realizado um programa experimental no Laboratório de Estruturas da EESC, uma análise numérica com o emprego do software DIANA® e uma comparação com formulações analíticas existentes para o cálculo da força última destes componentes. Foram ensaiados nove modelos experimentais para avaliar especificamente o mecanismo resistente do chumbador, variando-se os diâmetros das barras, sua inclinação e a porcentagem de fibras de aço no concreto. Além destes modelos, foi realizado ensaio de uma ligação viga-pilar de concreto pré-moldado para avaliar a rigidez da ligação com chumbador inserido em concreto com fibras de aço. Nos ensaios experimentais dos chumbadores observou-se que modelos com concreto com fibras de aço apresentam rigidez até 25% maior se comparado ao modelo com concreto convencional. Verificou-se que o graute utilizado para solidarizar os chumbadores exerce significativa influência na capacidade última do modelo, podendo diminuir em cerca de 30% a capacidade de carga. A ligação viga-pilar de concreto pré-moldado utilizando concreto com fibras de aço no consolo e no dente da viga se comportou de maneira satisfatória, não apresentando fissuração na interface dos diferentes concretos. Na comparação dos modelos ensaiados com as formulações teóricas extraídas de trabalhos de referência verificou-se que, para os modelos específicos de chumbador, a formulação existente é representativa. Para a ligação viga-pilar, alguns ajustes na formulação analítica se fizeram necessários para considerações de efeitos de grupo e de borda observados e decorrentes da utilização de dois chumbadores na ligação proposta neste trabalho. / This research deals with the study of the behavior of grouted dowels embedded in concrete with steel fibers. This study is important to understand and quantify the stiffness transmitted by this component in a semi-rigid connection of precast concrete structures. The objective is to study the mechanism of the dowel in the concrete with steel fibers and evaluate the mechanical behavior of a precast beam-column connection using this type of concrete on the corbels and in the dapped-end beam. In this research, an experimental program in the EESC Structures Laboratory was carried out, as well as a numerical analysis with the use of DIANA® software and a comparison with existing formulations to calculate these components. Nine models were experimentally tested to specifically evaluate the dowel resistant mechanism by varying the diameters of the bars, the declination and the percentage of steel fibers in concrete. Furthermore, an experimental test was performed in order to evaluate the behavior of the connector. The results indicate that for the dowels with concrete and steel fibers, the ultimate capacity of the connection occurs by failure of the connector (excessive deformation of the bars), while in conventional concrete this capability is associated with the rupture of the concrete and that the concrete with steel fibers decreases by 25% the deformability of the models. The grout has a significant impact on the ultimate capacity of the model, which may increase in less than 30%. In the analysis of the beam-column connection, it is possible to observe that the proposed connection exceeds by more than 20% the ultimate capacity compared to traditional beam-column connections. In comparing the theoretical models tested with the formulations shown by previous studies, it was found that for specific models dowels, the existing formulation is representative. For the beam-column connection, adjustment was performed in the previous formulation considerations group and edge effects that occur due to the use of two dowels on the tested connection.

Este trabalho apresenta uma análise da ligação pilar-fundação por meio de cálice em estruturas de concreto pré-moldado, focando os esforços nas paredes transversais do colarinho. No programa experimental foram ensaiados dois protótipos submetidos à flexão com grande excentricidade: um com interface pilar-colarinho lisa e o outro com interface rugosa por meio de chaves de cisalhamento. Foi adotado um detalhamento diferenciado para as armaduras verticais principais concentrando as mesmas próximas aos cantos, bem como foi adotada, para o colarinho, uma espessura inferior à recomendada pela literatura técnica. Com os resultados experimentais foi possível analisar a resistência dos protótipos, as deformações das armaduras e os deslocamentos das paredes. Foi realizada uma análise dos resultados experimentais com um modelo de cálculo da literatura técnica, no que diz respeito às forças resultantes nas armaduras verticais principais e nas armaduras horizontais principais situadas nas paredes transversais do colarinho, considerando duas situações distintas de comportamento para as paredes transversais: flexo-tração e tração. Em função dos resultados foi verificado que as armaduras verticais situadas próximo aos cantos contribuíram efetivamente para a resistência do protótipo com interface lisa. Comprovou-se que as paredes transversais foram submetidas a uma flexo-tração e que o modelo teórico aplicado considerando 15% de flexão e 85% de tração apresenta os melhores resultados, se comparados com os valores obtidos experimentalmente. / This research presents an analysis of socket base connections of precast concrete structures, with emphasis on the e orts of transverse walls. In the experimental program were tested two prototypes subjected to bending with great eccentricity: one with smooth interface, and other with rough interface through shear keys. It adopted a different detail for main vertical reiforcement, concentrating them around the corner, and was adopted for the socket, a thickness less than that recommended by the technical literature. Based on experimental results were performed the analysis of the strenght of prototypes, the deformations of the reinforcement, and the deflection of the walls. It was performed an analysis of experimental results with a design model of the technical literature regarding to the forces resulting in main vertical and horizontal reinforcement located on the transverse walls of socket, considering two different situations of behavior to transverse walls: bending-tension and tension. Analyzing the results, it was verified that the vertical reinforcement located near the corners effectively contributed to the strength of the prototype with smooth interface. It has been proved that the walls were subjected to a bending tension and that the theoretical model applied with 15% of bending and 85% of tension gives the best results, when compared with the values obtained experimentally.

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

O presente trabalho tem como objetivo desenvolver processos analíticos e programas computacionais para avaliação da estabilidade global e pré-dimensionamento de pórticos planos em concreto pré-moldado com base na garantia da estabilidade global. Em relação à avaliação da estabilidade global, são propostas duas expressões. A primeira está relacionada à expressão do limite do parâmetro de estabilidade aplicada a pórticos planos em concreto pré-moldado. A segunda expressão tem o objetivo determinar o deslocamento horizontal de topo de pórticos planos em concreto pré-moldado de um pavimento. A expressão do limite alternativo do parâmetro de estabilidade é deduzida a partir dos valores obtidos da relação entre o deslocamento horizontal médio e de topo de 1320 pórticos. A expressão é função do fator de restrição da ligação, contemplando, dessa forma, os efeitos causados pela semirrígidez das ligações no comportamento da estabilidade global desse sistema estrutural. A equação de determinação do deslocamento horizontal de topo de pórticos planos em concreto pré-moldado de um pavimento é deduzida com base no método dos deslocamentos. Em relação ao pré-dimensionamento de pórticos planos em concreto pré-moldado, são propostos processos analíticos para o pré-dimensionamento dos pilares de pórticos de um pavimento com ligação semirrígida e de pórticos de múltiplos pavimentos com ligações rígidas e articuladas. Os processos analíticos são constituídos pela expressão da rigidez equivalente de estabilidade de pórticos, desenvolvida através das equações do parâmetro de estabilidade e do seu limite alternativo. O trabalho ainda apresenta o Programa de Avaliação da Estabilidade Global e Pré-dimensionamento de Pórticos Planos em Concreto Pré-moldado, denominado PRE-MOLDIM. O programa é constituído por quatro módulos. O primeiro módulo realiza a avaliação da estabilidade global e verificação da deslocabilidade lateral de pórticos planos em concreto pré-moldado. O segundo módulo tem o objetivo de definir as dimensões mínimas dos pilares em função da garantia da estabilidade global e do deslocamento lateral admissível. O terceiro módulo define o valor da rigidez das ligações necessário para que sejam atendidos os quesitos de estabilidade global e deslocamento lateral admissível. O quarto módulo realiza o dimensionamento da armadura de continuidade de uma típica ligação viga-pilar em concreto pré-moldado. O dimensionamento da armadura de continuidade é realizado em função da garantia da estabilidade global e do deslocamento lateral admissível de pórticos planos em concreto pré-moldado. A aplicação dos processos analíticos e programas computacionais em exemplos comprovaram, de forma satisfatória, o desempenho de suas funções. Os valores obtidos pela expressão alternativa do limite do parâmetro de estabilidade são compatíveis com o limite do coeficiente \'gama\'z. Os valores do deslocamento de topo de pórticos de um pavimento com ligações semirrígidas, obtidos pelo processo analítico, são próximos dos valores obtidos pela simulação numérica. Os pilares pré-dimensionados pelos processos analíticos conseguem garantir de forma satisfatória estabilidade global dos pórticos planos em concreto pré-moldado. / The present work aims to develop analytical processes and computer programs for the evaluation of global stability and preliminary design of plane frames in precast concrete based on ensuring global stability. Regarding the evaluation of global stability, two analytical expressions are proposed. The first is related to the expression of the limit of the stability parameter applied to plane frames in precast concrete. The second expression has the objective to determine the horizontal displacement of the top of plane frames in precast concrete for a floor. The expression of the alternative stability limit of the parameter is deduced from the values obtained from the relationship between the average and the top horizontal displacement of 1320 frames. The expression is a function of the limiting factor of the connection, thus contemplating the effects caused by the semi-rigidity of the connection on the global stability behavior of this structural system. The equation for determining the horizontal displacement of the top of plane frames in precast concrete pavement is obtained based on the displacement method. Regarding the preliminary design of plane frames in precast concrete, analytical procedures are proposed for the preliminary design of column of an one store frame with semi-rigid connection and a multiple store frames with rigid and articulated connections. The analytical processes are constituted by the expression of equivalent stiffness of frame stability, developed through the equations of the stability parameter and its alternative limit. The work also presents the Program of Global Stability Evaluation and Preliminary Design of Plane Frames in Precast Concrete, called PRE-MOLDIM. The program consists of four modules. The first module performs the evaluation of global stability and verification of lateral plane frames displaceability in precast concrete. The second module aims to set minimum dimensions for the pillars due to guarantee the global stability and check the allowable lateral displacement. The third module defines the value of the connections stiffness so the matter of global stability and allowable lateral displacement are satisfied. The fourth module performs the design of continuity armor of a typical beam-column connection in precast concrete. The design armour continuity is made on the basis of ensuring the global stability and lateral displacement allowable plane frames in precast concrete. The application of analytical processes and computer programs in examples proved satisfactorily, the performance of its functions. The values obtained by the alternative expression of the limit of stability parameter are compatible with the limit of the coefficient \'gama\'z. The offset values top venting a pavement with semi-rigid connections, obtained by the analytical process, are close to the values obtained by numerical simulation. The preliminary designed pillars by analytical processes can ensure a satisfactory global stability of the plane frames in precast concrete.

No presente trabalho foram estudadas duas ligações viga-pilar de estruturas de concreto pré-moldado com ênfase na deformabilidade ao momento fletor. A primeira é muito utilizada em galpões com sistema estrutural de pórticos para telhado com duas águas. A segunda é utilizada em estruturas de edifícios com múltiplos pavimentos. Foram realizados ensaios físicos em dois modelos de cada tipo de ligação. Com base nos resultados experimentais, foram propostos modelos analíticos, baseados no Método dos Componentes, e realizadas simulações numéricas, baseadas no Método dos Elementos Finitos, através dos quais determinou-se a curva momento-rotação das ligações em estudo. As curvas momento rotação teóricas, para as duas ligações estudadas, ficaram bastante próximas das experimentais. De acordo com os resultados, pode-se dizer que a primeira ligação teve um comportamento próximo ao de uma ligação perfeitamente rígida. Isso porque, para uma estrutura típica, ela transmitiu mais de 90% do momento equivalente ao de uma estrutura monolítica. A segunda ligação também garantiu uma boa transferência de momento fletor. Observou-se que, ao considerar a semi-rigidez dessa ligação na análise estrutural, há uma redução significativa no momento na base dos pilares mais solicitados, o que permite uma redução na armadura dos pilares e nas dimensões da fundação / The present research deals with the study of two types of precast beam-to-column connections with emphasis on the deformability analysis. The first one is extensively used in precast concrete portal frames with sloping beams. The second one is used in multi-storey framed structures. Experimental tests on two models of each type of beam-to-column connections were done. Based on the experimental results, analytical models, based on the Component Method, were proposed and numerical simulations, based on the Finite Element Method, were developed, which provide the moment-rotation curves of the studied connections. The theoretical moment-rotation curves, for both studied connections, are in good agreement with the experimental ones. According to the results, the first connection had almost the same behaviour of a rigid one. It transmitted about 90% of the bending moment of an equivalent monolithic structure. The second connection also transmitted a good portion of bending moment. It was observed that when its semi-rigidity is considered on the structural analysis there was a significant reduction on the column base bending moment and on the foundation dimensions