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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
61

The Effects Of Non-Plastic and Plastic Fines On The Liquefaction Of Sandy Soils

Polito, Carmine Paul 20 January 2000 (has links)
The presence of silt and clay particles has long been thought to affect the behavior of a sand under cyclic loading. Unfortunately, a review of studies published in the literature reveals that no clear conclusions can be drawn as to how altering fines content and plasticity actually affects the liquefaction resistance of a sand. In fact, the literature contains what appears to be contradictory evidence. There is a need to clarify the effects of fines content and plasticity on the liquefaction resistance of sandy soils, and to determine methods for accounting for these effects in engineering practice. In order to help answer these questions, a program of research in the form of a laboratory parametric study intended to clarify the effects which varying fines content and plasticity have upon the liquefaction resistance of sandy sands was undertaken. The program of research consisted of a large number of cyclic triaxial tests performed on two sands with varying quantities of plastic and non-plastic fines. The program of research also examined the applicability of plasticity based liquefaction criteria and the effects of fines content and plasticity on pore pressure generation. Lastly, a review of how the findings of this study may affect the manner in which simplified analyses are performed in engineering practice was made. The results of the study performed are used to clarify the effects of non-plastic fines content and resolve the majority of the inconsistencies in the literature. The effects of plastic fines content and fines plasticity are shown to be different than has been previously reported. The validity of plasticity based liquefaction criteria is established, the mechanism responsible for their validity is explained, and a new simplified criteria proposed. The effects of fines content and plasticity on pore pressure generation are discussed, and several recommendations are made for implementing the findings of this study into engineering practice. / Ph. D.
62

Design, Syntheses and Biological Activities of Paclitaxel Analogs

Zhao, Jielu 03 May 2011 (has links)
The conformation of paclitaxel in the bound state on the protein has been proposed to be the T-taxol conformation, and paclitaxel analogs constrained to the T-taxol conformation proved to be significantly more active than paclitaxel in both cytotoxicity and tubulin polymerization assays, thus validating the T-taxol conformation as the tubulin-binding conformation. In this work, eight compounds containing an aza-tricyclic moiety as a mimic of the baccatin core of paclitaxel have been designed and synthesized as water-soluble simplified paclitaxel analogs, among which 3.50-3.52 and 3.55 were conformationally constrained analogs designed to bind to the paclitaxel binding site of tubulin, based on their similarity to the T-taxol conformation. The open-chain analogs 3.41-3.43 and 3.57 and the bridged analogs 3.50-3.52 and 3.55 were evaluated for their antiproliferative activities against the A2780 cell lines. Analogs 3.50-3.52 and 3.55 which were designed to adopt the T-taxol conformation showed similar antiproliferative activities compared to their open-chain counterparts. They were all much less active than paclitaxel. In the second project, a series of paclitaxel analogs with various thio-containing linkers at C-2′ and C-7 positions were designed and synthesized in our lab. These analogs were attached to the surfaces of gold nanoparticles by CytImmune Sciences for the development of mutifunctional tumor-targeting agents. The native analogs and the gold bound analogs were evaluated for their antiproliferative activities against the A2780 cell line. All the compounds tested showed comparable or better activities than paclitaxel. Stability studies were performed for selected analogs in hydrolysis buffer, which showed that the analogs released paclitaxel in buffer over time. In the third project, the synthesis of a conformationally constrained paclitaxel analog which was designed to mimic the REDOR-taxol conformation was attempted. Two synthetic routes were tried and significant progress was made toward the synthesis of the conformationally constrained analog. However, both of the current synthetic routes failed to produce the key intermediate that would serve as the precursor for a ring-closing metathesis reaction to furnish the macrocyclic ring. / Ph. D.
63

Förenklad riskbedömning av byggvaruprodukter innehållande kemiska ämnen : För anställdas hälsa på kommunalägda Bostads AB Mimer

Svensson, Sandra January 2015 (has links)
This bachelor thesis is about chemical products from the construction industry which are being used by the company Bostads AB Mimer (Mimer), owned by the municipality Västerås in Sweden. The company owns apartments and houses around the city. The aim of this bachelor thesis is to do a simplified risk assessment of the chemical products from a health and  environmental point. The report also gives suggestions of substitutional products. The thesis work consists of a literature study, an analysis of how other companies within the housing sector are working with chemical products and a case study, in addition to the simplified risk assessment. The case study contains a selection of Mimer's chemical products. In order to succeed with the simplified risk assessment, the chemical product’s risks and hazards has been identified through safety data sheets (SDS). Different aspects have been taken into account in the simplified risk assessment. The selection of the chemical products were made after existence frequency and legislative product labeling. The report's results gave 16 selected chemical products, that are risk assessed. Of the 16 chemical products, eight products have a high risk score from a heath point. Suggestions of less hazardous chemical products are given to nine chemical products. The essay's conclusions are that some of the selected chemical products are hazardous to the health and the environment, due to their chemical substances. The staff at Mimer's has a high frequency of use of the chemical products in general. Most of the other companies in the housing sector that  were investigated in the analysis, had a systematic work on chemicals.
64

K1 : Är det förenklade K1 regelverket användbart? / K1 : The simplified accounting rules for accounting in small businesses

Suleyman, Avare, Pettersson, Marcus January 2009 (has links)
<p> </p><p><strong>Sammanfattning</strong></p><p><strong> </strong></p><p><strong>Problem och bakgrund: </strong>Bokföringsnämnden (BFN) har arbetat fram ett regelverk för de enskilda näringsidkare som bör implementeras från den 1 januari 2007. Syftet anses vara bland annat att underlätta den administrativa bördan. Huvudfrågan som ställs i denna studie är en undran om, till vilken grad har användbarheten av K1 regelverket för de enskilda näringsidkarna förändrat redovisningsarbetet? De andra nyckelfrågorna är, har en effektivisering skett av redovisningsarbetet samt har det lett till väsentliga kostnadsbesparingar vad gäller den administrativa bördan?</p><p><strong>Syfte:</strong> Syftet med denna studie är att undersöka huruvida K1 regelverket har förenklat den administrativa arbetsbördan för enskilda näringsidkare, samt om det skett en effektivisering av arbetet med redovisningen.</p><p><strong>Metod: </strong>Studien tillämpar huvudsakligen den deduktiva forskningsmetoden med hjälp av statistisk datasamling. Detta innebär att studien utgår från en kvantitativ enkätundersökning med ett slumpmässigt urval av respondenter.</p><p><strong>Referensram: </strong>I studiens teoretiska referensram presenteras olika interrelaterade teorier som belyser K1 regelverkets motiv och funktion samt dess betydelse för redovisningen för de enskilda näringsidkarna i ett bredare perspektiv.<strong></strong></p><p><strong>Slutsats: </strong>Studiens syfte var att försöka förklara användbarheten av det nya K1 regelverket i samband med praktiken. Hur K1 regelverket har bidragit till en enklare redovisning och hur den har reducerat de administrativa kostnaderna.</p><p>Studiens resultat visar att det förenklade årsbokslutet används i väldigt liten skala bland deltagande respondenter i undersökningen. Största orsaken till att K1 regelverket inte används i den utsträckning som förväntats är bristen på information och kunskap hos de enskilda näringsidkarna om K1:s strukturella form och funktion. Då få respondenter använder sig av ett förenklat årsbokslut, blev det svårt att på ett adekvat sätt besvara hur väl det lett till att de administrativa kostnaderna har minskats.</p> / <p> </p><p><strong>Abstract</strong></p><p><strong> </strong></p><p><strong>Problem and background:</strong> The Swedish Accounting Standards Board (BFN) has issued a set of standards for small businesses that have been implemented since January the 1<sup>st</sup> 2007. The purpose of these standards is to facilitate and simply the administrative burden. This study poses the question "To what extent has the usability of the K1 framework for small businesses changed the accounting workload? Has there been a streamlining of the accounting workload and has it led to significant cost savings in terms of administrative burden."</p><p><strong>Aim of this study:</strong> The aim of this study is to investigate whether the K1 framework has simplified the administrative workload for small businesses, and if it has led to a streamlining of the process of accounting.</p><p><strong>Method:</strong> The study applies mostly to the deductive research method with the aid of statistical data collection. This means that the study is based on a quantitative survey of a random sample of respondents.</p><p> </p><p><strong>Frame of references:</strong> In the study's theoretical frame of reference various inter-related theories are presented, highlighting the motives behind the K1 framework as well as its functions and its importance to the workload in preparing the financial statements for sole trade businesses in a broader perspective.</p><p> </p><p><strong>Conclusion:</strong> The study's main objective was to try to explain the usefulness of the new K1 framework in the context of its use in practice. How the K1 framework contributed to a simpler accounting and how it has reduced the administrative costs.</p><p>The results of the study show that only a small set of the respondents to the survey use the simplified annual accounts from the K1 framework. The principal reason that the K1 framework is not used to the extent expected, is due to the lack of awareness by the small businesses on the K1 framework's structural form and function. It is evident that more could have been done to widen the knowledge and information on the K1 framework. Given that only a small subset of the respondents use the simplified annual accounts from the K1 framework, it is not adequate to conclude on how well the framework has been used to lessen the administrative costs and burdens.</p>
65

[en] SIMPLIFIED MATHEMATICAL MODEL FOR MIGRATION OF GAS BUBBLES IN VISCOPLASTIC / [pt] MODELO MATEMÁTICO SIMPLIFICADO PARA MIGRAÇÃO DE BOLHAS DE GÁS EM FLUIDO VISCOPLASTICO

WILLIAM FERNANDO LOPEZ CANDELA 02 May 2014 (has links)
[pt] Neste trabalho, um estudo do deslocamento ascendente de uma única bolha de gás num fluido não newtoniano é realizado ,a fim de simular o escoamento de bolhas de gás em pasta de cimento durante a cimentação de poços de petróleo. O fluido é modelado como um fluido não Newtoniano tipo Herschel-Bulkley com reologia variável no tempo. A partícula imersa no fluido não necessariamente é gasosa, também pode ser sólida ou liquida, fazendo algumas considerações para cada caso. Para desenvolver o modelo matemático foi feita uma analise dinâmica da partícula esférica imersa no fluido, e junto com as equações de Ansley e Plesley (1967), foi finalizado o modelo. O sistema de equações foi solucionado usando um método numerico de Runge Kutta de baixa ordem. O modelo numérico foi implementado usando o programa Matlab da empresa Mathworks. Os cálculos foram feitos para bolha esférica, numero de Reynolds baixo (menor 3), temperatura constante, efeito de parede desprezível e sem efeito de população. O modelo foi validado comparando os resultados numéricos com os resultados experimentais de multiples autores. Foram consultados os dados experimentais dos autores Raymond (2000), Hervé Tabuteau (2007) e Neville Dubash (2003). Foi analisado o efeito da massa da bolha e da tensão superficial da interface liquido-gás na cinemática da partícula, a fim de definir em que condições é possível desprezar seus efeitos. Finalmente, os efeitos dos parâmetros reológicos na cinemática da partícula são analisados. Além disso, considerou-se a dependência da reologia com o tempo a fim de analisar o processo de deslocamento da bolha durante a cura do cimento. / [en] In this work, a study of the rising movement of single gas bubble in non- Newtonian fluid is performed, in order to simulate the behavior of a gas bubble in a cement paste during oil well cementing. The fluid is modeled as a non- Newtonian fluid type Hershchel-bulkley with varying rheology in the time. The particle immersed in the fluid is not necessarily gaseous, it also could be liquid or solid, with some restrictions for each case. To develop the mathematical model, it was done a dynamic analysis of the spherical particle immersed in the fluid, and also, using the Ansley and Plesley’s equations (1967), was finished the model. The equation systems was solved using a low order numerical method of Runge Kutta. The numerical model was implemented using Matlab program of the Mathworks Company. The calculations were made for spherical bubble, low Reynolds number (less than 3), constant temperature, wall effect neglected and without effect population.The model was validated comparing the numerical data with experimental results of multiple authors. Experimental data was consulted of Raymond and Rosant (2000), Hervé Tabuteau (2007) and Neville Dubash (2003) authors. It was analyzed the bubble mass effect and the surface tension of the liquid-gas interface in the kinematic particle, to define under what conditions it is possible to neglected its effects. Finally,the effects of rheological parameters on particle kinematics was analized. furthermore, the dependence of the rheology in the time to determine the bubble displacement process in the curing cement was analized.
66

Análise não-linear física simplificada de estruturas de contraventamento de edifícios de alvenaria estrutural / Simplified physical non-linear analysis on shear wall masonry buildings

Gomes, Denise Itajahy Sasaki 19 May 2010 (has links)
Neste trabalho são discutidos os aspectos referentes à análise não-linear física de painéis de contraventamento em alvenaria estrutural. O objetivo foi a obtenção de coeficientes a serem aplicados ao produto de rigidez à flexão (EI) para a consideração da não-linearidade física de forma simplificada. As estruturas foram analisadas de forma paramétrica através de um modelo de elementos finitos lineares (pórtico plano), com a utilização de duas diferentes taxas de armaduras para uma combinação de ação horizontal e vertical aplicada. A ação horizontal limitou o deslocamento do topo do painel em H/3500, nas análises lineares. A ação vertical simulou a reação de uma laje com peso próprio e sobrecargas de utilização. A alvenaria foi considerada como um meio contínuo e homogêneo (macro-modelos). Foi apresentada uma metodologia para a obtenção do coeficiente de rigidez à flexão para ser aplicado nas análises lineares e simular o efeito da não-linearidade física. Os valores do coeficiente de redução do produto de rigidez à flexão apresentaram-se muito baixos, com uma variação de 0,1 a 0,4, sugerindo a verificação do modelo matemático bem como do programa utilizado nas análises. / This study deals with aspects related to the nonlinear analysis of physical shear walls in masonry. The objective was to obtain coefficients to be applied to the product of bendind stiffness (EI) for considering physically nonlinear behavior in a simplified analysis. The structures were analyzed usig a parametric finit element model using linear elements (plane frame), with two different reinforcement ratios for one combination of horizontal and vertical actions. The horizontal action limited de top displacement of the shear wall in H/3500. The vertical loads simulated the reaction of a slab with self-weight and burdens of use. The masonry was considered as a means continuous and homogeneous (Macro-models). Was presented a methodology for obtaining the coefficient of bending stiffness to be applied in linear analysis and simulate the effect of non-linearity. The coefficient of reduction product of bending stiffness were very low, with a variation of 0.1 to 0.4, suggesting the verification of mathematical model and the program used in the analysis.
67

Análise não-linear física simplificada de estruturas de contraventamento de edifícios de alvenaria estrutural / Simplified physical non-linear analysis on shear wall masonry buildings

Denise Itajahy Sasaki Gomes 19 May 2010 (has links)
Neste trabalho são discutidos os aspectos referentes à análise não-linear física de painéis de contraventamento em alvenaria estrutural. O objetivo foi a obtenção de coeficientes a serem aplicados ao produto de rigidez à flexão (EI) para a consideração da não-linearidade física de forma simplificada. As estruturas foram analisadas de forma paramétrica através de um modelo de elementos finitos lineares (pórtico plano), com a utilização de duas diferentes taxas de armaduras para uma combinação de ação horizontal e vertical aplicada. A ação horizontal limitou o deslocamento do topo do painel em H/3500, nas análises lineares. A ação vertical simulou a reação de uma laje com peso próprio e sobrecargas de utilização. A alvenaria foi considerada como um meio contínuo e homogêneo (macro-modelos). Foi apresentada uma metodologia para a obtenção do coeficiente de rigidez à flexão para ser aplicado nas análises lineares e simular o efeito da não-linearidade física. Os valores do coeficiente de redução do produto de rigidez à flexão apresentaram-se muito baixos, com uma variação de 0,1 a 0,4, sugerindo a verificação do modelo matemático bem como do programa utilizado nas análises. / This study deals with aspects related to the nonlinear analysis of physical shear walls in masonry. The objective was to obtain coefficients to be applied to the product of bendind stiffness (EI) for considering physically nonlinear behavior in a simplified analysis. The structures were analyzed usig a parametric finit element model using linear elements (plane frame), with two different reinforcement ratios for one combination of horizontal and vertical actions. The horizontal action limited de top displacement of the shear wall in H/3500. The vertical loads simulated the reaction of a slab with self-weight and burdens of use. The masonry was considered as a means continuous and homogeneous (Macro-models). Was presented a methodology for obtaining the coefficient of bending stiffness to be applied in linear analysis and simulate the effect of non-linearity. The coefficient of reduction product of bending stiffness were very low, with a variation of 0.1 to 0.4, suggesting the verification of mathematical model and the program used in the analysis.
68

K1 : Är det förenklade K1 regelverket användbart? / K1 : The simplified accounting rules for accounting in small businesses

Suleyman, Avare, Pettersson, Marcus January 2009 (has links)
Sammanfattning Problem och bakgrund: Bokföringsnämnden (BFN) har arbetat fram ett regelverk för de enskilda näringsidkare som bör implementeras från den 1 januari 2007. Syftet anses vara bland annat att underlätta den administrativa bördan. Huvudfrågan som ställs i denna studie är en undran om, till vilken grad har användbarheten av K1 regelverket för de enskilda näringsidkarna förändrat redovisningsarbetet? De andra nyckelfrågorna är, har en effektivisering skett av redovisningsarbetet samt har det lett till väsentliga kostnadsbesparingar vad gäller den administrativa bördan? Syfte: Syftet med denna studie är att undersöka huruvida K1 regelverket har förenklat den administrativa arbetsbördan för enskilda näringsidkare, samt om det skett en effektivisering av arbetet med redovisningen. Metod: Studien tillämpar huvudsakligen den deduktiva forskningsmetoden med hjälp av statistisk datasamling. Detta innebär att studien utgår från en kvantitativ enkätundersökning med ett slumpmässigt urval av respondenter. Referensram: I studiens teoretiska referensram presenteras olika interrelaterade teorier som belyser K1 regelverkets motiv och funktion samt dess betydelse för redovisningen för de enskilda näringsidkarna i ett bredare perspektiv. Slutsats: Studiens syfte var att försöka förklara användbarheten av det nya K1 regelverket i samband med praktiken. Hur K1 regelverket har bidragit till en enklare redovisning och hur den har reducerat de administrativa kostnaderna. Studiens resultat visar att det förenklade årsbokslutet används i väldigt liten skala bland deltagande respondenter i undersökningen. Största orsaken till att K1 regelverket inte används i den utsträckning som förväntats är bristen på information och kunskap hos de enskilda näringsidkarna om K1:s strukturella form och funktion. Då få respondenter använder sig av ett förenklat årsbokslut, blev det svårt att på ett adekvat sätt besvara hur väl det lett till att de administrativa kostnaderna har minskats. / Abstract Problem and background: The Swedish Accounting Standards Board (BFN) has issued a set of standards for small businesses that have been implemented since January the 1st 2007. The purpose of these standards is to facilitate and simply the administrative burden. This study poses the question "To what extent has the usability of the K1 framework for small businesses changed the accounting workload? Has there been a streamlining of the accounting workload and has it led to significant cost savings in terms of administrative burden." Aim of this study: The aim of this study is to investigate whether the K1 framework has simplified the administrative workload for small businesses, and if it has led to a streamlining of the process of accounting. Method: The study applies mostly to the deductive research method with the aid of statistical data collection. This means that the study is based on a quantitative survey of a random sample of respondents.   Frame of references: In the study's theoretical frame of reference various inter-related theories are presented, highlighting the motives behind the K1 framework as well as its functions and its importance to the workload in preparing the financial statements for sole trade businesses in a broader perspective.   Conclusion: The study's main objective was to try to explain the usefulness of the new K1 framework in the context of its use in practice. How the K1 framework contributed to a simpler accounting and how it has reduced the administrative costs. The results of the study show that only a small set of the respondents to the survey use the simplified annual accounts from the K1 framework. The principal reason that the K1 framework is not used to the extent expected, is due to the lack of awareness by the small businesses on the K1 framework's structural form and function. It is evident that more could have been done to widen the knowledge and information on the K1 framework. Given that only a small subset of the respondents use the simplified annual accounts from the K1 framework, it is not adequate to conclude on how well the framework has been used to lessen the administrative costs and burdens.
69

Enklare redovisning : Granskning av Statens Offentliga Utredning 2008:67 / Simplified Accounting : Review of the Swedish Government Official Report 2008:66

Lexell, Anna, Lindstedt, Kristina, Valkonen-Evertsson, Marina January 2009 (has links)
Regeringen gav år 2007 en grupp i uppdrag att leda förenklingen gällande enklare redovisning som en del av det stora förenklingsarbetet i Sverige. Förenklingsarbetet går ut på att sänka de administrativa lagreglerade kostnaderna för svenska företag med 25 procent till 2010. Under 2008 presenterades en av åtgärderna inom förenklingsarbetet; ”Delbetänkandet om Enklare redovisning – SOU 2008:67”. Några av de föreslagna förändringarna innebära att normgivande organ och i synnerhet Bokföringsnämnden ges mer ansvar genom utökad normgivning. I och med att förslaget presenterar flera ändringar som kan påverka företag, intressenter och revisorer, var det intressant att undersöka remissinstansernas svar och kommentarer till utredningen. Samtidigt var det intressant och se hur revisorer ser på utredningen, då de ofta har en annan insynsvinkel. Syftet lyder därför som följer: Syftet med denna uppsats är att undersöka hur revisionsbolag och remissinstanser till SOU:n uppfattar förslaget om Enklare redovisning (SOU 2008:67). Undersökningen är gjord utifrån en så kallad fenomenografisk metod, vilket innebär att det endast är remissinstansernas och revisorernas uppfattningar som har undersökts – inte hur det faktiskt är. En stor del av arbetetstiden har distribuerats till att läsa, tolka och förstå utredningen samtidigt som mycket av innehållet har fått kompletterats och undersökts i annan litteratur. Intervjuerna har gjorts via personliga möten samt internetbaserade dialoger i form av e-post. Resultatet visar att alla välkomnar förenklingsarbetet och anser att det är viktigt, då svenska företag ska ha en jämförlig konkurrensmöjlighet gentemot europeiska företag. Vissa av aspekterna, såsom borttagandet av det vanliga årsbokslutet, har bemötts positivt av remissinstanserna, men inte från revisorerna. Slutsatsen av detta är att från ett bredare intressentperspektiv, spelar inte det vanliga årsbokslutet en avgörande roll. Borttagandet av förvaltningsberättelsen för mindre företag anses som onödigt då den mesta informationen ändå kommer att bibehållas i noterna. Då de flesta mindre företag har mer eller mindre standardiserade förvaltningsberättelser, innebär det ändå ingen förenkling, utan kanske till och med en försvåring. / During 2007, the Swedish government issued a group to be in charge of the simplification regarding simpler accounting as a part of the large simplification in Sweden. The goal is to lower the administrative costs that are regulated by law with 25 per cent until 2010. During 2008, one of the Swedish Government Official Reports regarding the simplification was presented named; ”Delbetänkandet om Enklare redovisning – SOU 2008:67”. Some of the suggested changes would result in that normative organs, and especially the Swedish Accounting Standard Board, should be given more responsibility through standardsetting. Since the proposal presents several changes that could affect companies, interested parties and auditors, the authors found it interesting to investigate the answers and comments from consultation bodies of the proposal. At the same time, it was interesting to investigate how the auditors perceive the proposal, since they often has another point of view. The purpose is therefore: The purpose with this thesis is to investigate how auditing firms and consultation bodies to the Swedish Government Official Report perceive the proposal regarding simplified accounting. (SOU 2008:67) The investigation is done from a phenomenographical method, which means that it is only the consultation bodies and the auditors’ perception that is investigated – not how the reality actually is. A large part of the working hours has been distributed to read, interpret and understand the investigation. At the same time, a lot of the content had to be complemented and investigated in literature. The interviews have been done through face-to-face dialogues and via e-mail dialogues. The result shows that everyone welcomes the simplification and believes it is important, since Swedish companies should have an even chance towards the rest of Europe when it comes to competition. Some of the aspects, such as the removal of the “ordinary” annual accounts, have been treated positively from the consultation bodies, but not from the auditors. The conclusion from this is that from the interested parties’ point of view, the ordinary annual accounts are not considered to be of great importance. The removal of the management report for smaller companies is perceived as unnecessary, since most of the content will be kept and placed in the notes. Since most of the smaller companies have more or less standardized management reports, will the change not result in a simplification, but perhaps instead make it even more difficult.
70

An Investigation Of The Inertial Interaction Of Building Structures On Shallow Foundations With Simplified Soil-structure Interaction Analysis Methods

Eyce, Bora 01 September 2009 (has links) (PDF)
Seismic response of a structure is influenced by the inertial interaction between structure and deformable medium, on which the structure rests, due to flexibility and energy dissipation capability of the surrounding soil. The inertial interaction analyses can be performed by utilizing simplified soil-structure interaction (SSI) analyses methods. In literature, it is noted that varying soil conditions and foundation types can be modeled by using these SSI approaches with springdashpot couples having certain stiffness and damping. In this study, the seismic response of superstructure obtained by using simplified SSI methods is compared with those of the fixed base systems. For this purpose, single and multi degree of freedom structural systems are modeled with both spring&ndash / dashpot couple and fixed base models. Each system is analyzed for varying structural and soil stiffness conditions under the excitation of three different seismic records. Next, the total base shear acting on the structural system and internal forces of load bearing members are investigated to observe the inertial interaction and foundation uplift effects on the superstructure. It is also aimed to examine the compatibility of the simplified SSI approaches utilized in the analyses. It is concluded that the structural and soil stiffness parameters are the most influential parameters that affect seismic structural response. Structures becomemore sensitive to varying soil properties as the structural stiffness increases. On the other hand, decreasing soil stiffness also increases the sensitivity of the structure to the seismic excitation. Calculated values of total base shear and internal member forces revealed that the inertial interaction might be detrimental for the superstructure. Contrary to general belief, the fixed base approach does not always yield to the results, which are on the safe side. Considering the analysis results, it is concluded that SSI analysis is very useful for more precise and economical design for the seismic behavior.

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