abstract: Saudi Arabia has been having many issues with large construction projects such as delays, low performance and high cost. Some studies show that around 70% of the public projects in Saudi Arabia are delayed. These issues have resulted from many factors. One of the factors believed to be delaying projects is the Saudi procurement system. The Saudi procurement system only selects contracts based on the lowest bid price offered. However, the Saudi procurement system has been found to not only produce delayed low quality projects, but also has resulted in higher costs. This paper shows how to modify the Saudi procurement system by implementing a clarification phase, which is the most important phase in the Performance Information Procurement System (PIPS). The clarification phase requires the bid’s winning contractor to submit a project scope, a project schedule, to identify risks that not their responsibility, performance measurements and a milestone schedule. The PIPS system has been one of the most successful systems around the world and has shown a 98% success rate in six different countries with risks and cost reductions up to 30%. This research conducted a survey of 157 engineers, 33 consultants, 9 owners, 5 vendors, 13 academics, and 28 architects to develop the public procurement system in Saudi Arabia. The participants work in government sectors with an interest in the Saudi Arabian procurement system. 80.61 % of participants believe that the traditional Saudi procurement system consistently selects poor performing contractors. Moreover, 95.97% of participants think that the selection of contractors based only on the lowest price criterion affects projects negatively. Also, 96.20% of participants in the survey feel that there needs to be a change in the traditional Saudi Arabian procurement system. 88.7% of participants agree to require the contractor to identify risks, and 96.03 % of participants agree that the contractors must have a plan. Moreover, 95.45% of participants agree to require a contractor review the scope of a project and verify that it is correct. Finally, 82.18% of participants agree to require a contractor to resolve all owner concerns before signing a contract to improve construction projects performance. The paper shows the need to change the Saudi procurement system and a solution to this growing problem. / Dissertation/Thesis / Masters Thesis Construction 2015

No description available.

Both construction Waste Minimisation (WM) and construction procurement activities play an effective role in attaining sustainability by giving due consideration to the environment, community and social conditions in delivering built assets. The construction industry has a major impact on the environment, both in terms of resource consumption and increasing waste production. Recent figures published by the UK government reveal that construction and demolition activities produce approximately 32% of total waste generated: three times the waste produced by all households combined. However, the current and on-going research in the field of construction WM and management focuses mainly on onsite waste quantification and management; and stakeholders‟ source identification. Little research has been undertaken to evaluate the relationship between Construction Procurement Systems (CPS) and construction waste generation. However, literature emphasises the need for research in this context. This research aims to develop a Procurement Waste Minimisation Framework (PWMF) to enhance WM practices by evaluating the relationship between CPS and construction waste generation. Objectives of the research include: examine construction WM drivers, WM approaches, waste origins and causes; critically review and evaluate current CPS and sustainable procurement practices in the UK; assess the relationship between CPS and construction waste generation; investigate and synthesis Procurement Waste Origins (PWO); examine the most suitable CPS that could potentially embed and sustain WM; develop and validate the PWMF. This research has adopted a survey research design and mixed methods sequential procedure. Data has been gathered through a cross sectional, self-administered postal questionnaire survey (N=258 distributed, n=65 received) and semi-structured interviews (N=17) with procurement managers and sustainability managers from the top 100 UK contracting organisations and quantity surveyors from the top 100 UK quantity surveying organisations. Data analysis techniques include: descriptive statistics; non-parametric tests; and constant comparative method. The PWMF has developed based on the findings of literature review, questionnaire survey and semi-structured interviews and adopting key concepts of problem solving methodology. The PWMF validation method includes: validation questionnaire (N=8) and follow-up semi-structured interviews (N=6) with procurement managers, sustainability managers and quantity surveyors. Key findings which emerged from the study include: CPS do have an impact on waste generation in construction; integrated CPS have major potential to integrate WM strategies; four PWO identified (i.e. uncoordinated early involvement of project stakeholders; ineffective communication and coordination; unclear allocation of WM responsibilities; and inconsistent procurement documentation) and associated sub-waste causes; and the developed PWMF enables to diagnose potential waste origins and causes, and WM improvement measures for design and build projects. The study has made recommendations which, if adopted, will lead to significant improvements in WM practices and sustainable procurement practices in construction. The content should be of interest to contractors, clients, and organisations dealing with procurement, waste and sustainability.

Submitted by Suethene Souza (suethene.souza@ufpe.br) on 2015-03-03T18:32:34Z No. of bitstreams: 2 DissertacaoDesignBuild.pdf: 3398710 bytes, checksum: ef609f38cfa0477d8bd3c9f076675594 (MD5) license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) / Made available in DSpace on 2015-03-03T18:32:34Z (GMT). No. of bitstreams: 2 DissertacaoDesignBuild.pdf: 3398710 bytes, checksum: ef609f38cfa0477d8bd3c9f076675594 (MD5) license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Previous issue date: 2012-05-31 / Este estudo objetiva identificar as contribuições do método design-build, bem como riscos envolvidos na sua adoção, com vistas à minimização de problemas entre projeto e construção de obras públicas, oriundos em parte da dissociação entre projeto e construção imposta pela legislação brasileira ao determinar contratações distintas para ambos. Para que as contribuições do método fossem visualizadas foi necessário compará-lo ao que atualmente é utilizado pela Administração, método design-bid-build. Assim, foi realizado um estudo de caso de natureza qualitativa, no qual foram realizadas pesquisas documentais e de campo, na forma de entrevistas. Sobre os dados documentais e de campo foi aplicada análise de conteúdo, bem como triangulação de métodos e fontes, o que possibilitou investigar os problemas sob pontos de vistas diversos, captados por métodos diferentes, oferecendo um panorama bem mais próximo da realidade. Dentre os problemas identificados figuram falta de interação direta entre projetistas e construtoras, prazos irreais determinados pelo contratante para elaboração dos projetos e longo período de tempo entre concepção do projeto e efetiva execução da obra. Identificados os problemas foi verificado quais deles poderiam ser solucionados ou minimizados com a adoção do método de contratação design-build, considerando sua principal característica de concepção do projeto e execução da obra realizados por uma única empresa, em uma única contratação. Ao mesmo tempo, com vistas a uma possível adoção do método, foram levantados aspectos negativos, riscos prováveis e respectivas estratégias de enfrentamento. Dentre os aspectos críticos observados pelos entrevistados sobressaíram a possibilidade da empresa contratada se beneficiar elaborando um projeto ajustado às suas disponibilidades e não à real necessidade do contratante, associada à falta de estrutura dos órgãos públicos para exercerem o controle requerido pelo método design-build. Verificou-se que o método design-build seria uma solução possível para alguns dos problemas encontrados. Entretanto, o contratante deve precaver-se dos aspectos negativos e riscos possíveis, adotando medidas que eliminem ou minimizem seus efeitos. Os resultados encontrados contribuirão certamente não apenas para uma possível implantação do método, em contextos inclusive distintos do público, como também para a melhoria dos processos concernentes a projeto e execução de obras, independente do método de contratação porventura utilizado. No âmbito acadêmico poderá contribuir incentivando a realização de mais pesquisas sobre projeto e execução de empreendimentos de construção

Recently, the wavy leading edge airfoils, inspired by the humpback whale´s flipper, have been investigated, as flow control mechanisms, at low Reynolds numbers in order to improve aerodynamic performance in this particular flow regime. The overall aim of this work is to investigate the airfoil geometric effects on wavy leading edge phenomena in the low Reynolds number regime. Experimental investigations were carried out correlating force measurements with mini-tuft and oil visualizations in order to understand the airfoil thickness effects on wavy leading edge phenomena. Three sets of airfoil thickness were tested (NACA 0012, NACA 0020 and NACA 0030), each set consisting of smooth plus three wavy configurations (A=0.11c, ?=0.40c; A=0.03c, ?=0.40c and A=0.03c, ?=0.11c); Reynolds number was varied between 50,000 and 290,000. The results present many findings that were not possible in previous studies due the fact that these investigations were constrained to specific geometries and/or flow conditions. At higher Reynolds number, the decrease in airfoil thickness leads the airfoils to leading edge stall characteristics causing the lowest aerodynamic deterioration for the thinnest wavy airfoil as compared to smooth configuration in the pre-stall regime. In addition, the results show impressive tubercle performance in the lowest Reynolds number. For any tubercle geometry and airfoil thickness, the wavy leading edge airfoils present higher maximum lift values as compared to smooth configurations showing an unprecedented increase in performance for a full-span model tested in the literature. The flow visualizations present two flow mechanisms triggered by secondary flow: three-dimensional laminar separation bubbles and vortical structures. Regarding three-dimensional laminar bubbles, the results confirm some of the few previous experimental and numerical studies, and presents for the first time these structures as a very efficient flow control mechanism in the post-stall regime justifying the impressive increase in maximum lift in the lowest Reynolds number. Besides that, two characteristics of laminar bubbles, \"tipped-bubbles\" and \"elongated-bubbles\", are identified with different effects in the pre-stall regime. This thesis presents higher tubercle performance for thinner airfoils (NACA 0012) and/or lower Reynolds number conditions (Re=50,000) showing clearly that an optimum performance lead the \"tubercles\" to operate under conditions of leading edge flow separation conditions. Therefore, a design space for tubercles conducted to leading edge stall characteristics confirming the hypothesis of Stanway (2008) eight years before. / Recentemente, aerofólios com bordo de ataque ondulados, inspirados na nadadeira da baleia jubarte, tem sido investigados como mecanismo de controle de escoamento para baixo número de Reynolds com a finalidade de se aumentar o desempenho aerodinâmico neste específico regime de escoamento. O objetivo geral deste trabalho é investigar os efeitos geométricos do aerofólio nos fenômenos do bordo de ataque ondulado na condição de baixo número de Reynolds. Investigações experimentais foram realizadas correlacionando medições de forças com visualizações de lã e óleo a fim de compreender os efeitos da espessura do aerofólio sobre os fenômenos de bordo de ataque ondulado. Três conjuntos de espessura de aerofólios foram testados (NACA 0012, NACA 0020 e NACA 0030) na faixa de número de Reynolds entre 50,000 e 290,000, onde cada conjunto tem um aerofólio liso e três ondulados (A = 0.11c, ? = 0.40c; A = 0.03c, ? = 0.40c e A = 0.03c, 0.11c ? =0.11c). O dados experimentais mostram importantes resultados que não foram possíveis em estudos anteriores devido às investigações serem restritas à geometria ou/e condição de escoamento específicas. O resultados de medida de força mostram que a diminuição da espessura do aerofólio conduz às características de separação de escoamento de bordo de ataque que causam menor deterioração aerodinâmica nos aerofólios ondulados finos quando comparados aos lisos no regime de pré-stall. Além disso, os resultados mostram um desempenho destacado do bordo de ataque ondulado para condição de menor número de Reynolds. Em quaisquer espessuras de aerofólio, os bordos ondulados apresentam valores de sustentação máxima maiores quando comparado aos aerofólios lisos mostrando assim resultado inédito na literatura para modelos ondulados bi-dimensionais. As visualizações de óleo evidenciaram dois mecanismos de controle de escoamento desencadeadas pelo escoamento secundário: bolhas de separação laminar tridimensionais e estruturas vorticais. Os resultados confirmam alguns poucos estudos experimentais e numéricos anteriores relacionadas com bolhas tridimensionais, e apresenta pela primeira vez estas estruturas como um mecanismo muito eficiente de controle de escoamento em regime de pós-stall justificando o aumento de máxima sustentação para o menor número de Reynolds. Adicionalmente, foram identificadas duas estruturas de bolhas tridimensionais nomeados aqui como \"bolhas com pontas\" e \"bolhas alongadas\" que causam distintos efeitos no regime de pré-stall. Esta tese apresenta como resultado maior desempenho para aerofólios ondulados com menor espessura (NACA 0012) e/ou para condições de menor número de Reynolds (Re=50,000)mostrando claramente que estas características levam as ondulações a operarem em condições de stall de bordo de ataque assim tendo um desempenho superior. Portanto, um espaço de projeto para tubérculos conduz às características de stall de bordo de ataque confirmando a suposição de Stanway (2008) oitos anos antes.

Recently, the wavy leading edge airfoils, inspired by the humpback whale´s flipper, have been investigated, as flow control mechanisms, at low Reynolds numbers in order to improve aerodynamic performance in this particular flow regime. The overall aim of this work is to investigate the airfoil geometric effects on wavy leading edge phenomena in the low Reynolds number regime. Experimental investigations were carried out correlating force measurements with mini-tuft and oil visualizations in order to understand the airfoil thickness effects on wavy leading edge phenomena. Three sets of airfoil thickness were tested (NACA 0012, NACA 0020 and NACA 0030), each set consisting of smooth plus three wavy configurations (A=0.11c, ?=0.40c; A=0.03c, ?=0.40c and A=0.03c, ?=0.11c); Reynolds number was varied between 50,000 and 290,000. The results present many findings that were not possible in previous studies due the fact that these investigations were constrained to specific geometries and/or flow conditions. At higher Reynolds number, the decrease in airfoil thickness leads the airfoils to leading edge stall characteristics causing the lowest aerodynamic deterioration for the thinnest wavy airfoil as compared to smooth configuration in the pre-stall regime. In addition, the results show impressive tubercle performance in the lowest Reynolds number. For any tubercle geometry and airfoil thickness, the wavy leading edge airfoils present higher maximum lift values as compared to smooth configurations showing an unprecedented increase in performance for a full-span model tested in the literature. The flow visualizations present two flow mechanisms triggered by secondary flow: three-dimensional laminar separation bubbles and vortical structures. Regarding three-dimensional laminar bubbles, the results confirm some of the few previous experimental and numerical studies, and presents for the first time these structures as a very efficient flow control mechanism in the post-stall regime justifying the impressive increase in maximum lift in the lowest Reynolds number. Besides that, two characteristics of laminar bubbles, \"tipped-bubbles\" and \"elongated-bubbles\", are identified with different effects in the pre-stall regime. This thesis presents higher tubercle performance for thinner airfoils (NACA 0012) and/or lower Reynolds number conditions (Re=50,000) showing clearly that an optimum performance lead the \"tubercles\" to operate under conditions of leading edge flow separation conditions. Therefore, a design space for tubercles conducted to leading edge stall characteristics confirming the hypothesis of Stanway (2008) eight years before. / Recentemente, aerofólios com bordo de ataque ondulados, inspirados na nadadeira da baleia jubarte, tem sido investigados como mecanismo de controle de escoamento para baixo número de Reynolds com a finalidade de se aumentar o desempenho aerodinâmico neste específico regime de escoamento. O objetivo geral deste trabalho é investigar os efeitos geométricos do aerofólio nos fenômenos do bordo de ataque ondulado na condição de baixo número de Reynolds. Investigações experimentais foram realizadas correlacionando medições de forças com visualizações de lã e óleo a fim de compreender os efeitos da espessura do aerofólio sobre os fenômenos de bordo de ataque ondulado. Três conjuntos de espessura de aerofólios foram testados (NACA 0012, NACA 0020 e NACA 0030) na faixa de número de Reynolds entre 50,000 e 290,000, onde cada conjunto tem um aerofólio liso e três ondulados (A = 0.11c, ? = 0.40c; A = 0.03c, ? = 0.40c e A = 0.03c, 0.11c ? =0.11c). O dados experimentais mostram importantes resultados que não foram possíveis em estudos anteriores devido às investigações serem restritas à geometria ou/e condição de escoamento específicas. O resultados de medida de força mostram que a diminuição da espessura do aerofólio conduz às características de separação de escoamento de bordo de ataque que causam menor deterioração aerodinâmica nos aerofólios ondulados finos quando comparados aos lisos no regime de pré-stall. Além disso, os resultados mostram um desempenho destacado do bordo de ataque ondulado para condição de menor número de Reynolds. Em quaisquer espessuras de aerofólio, os bordos ondulados apresentam valores de sustentação máxima maiores quando comparado aos aerofólios lisos mostrando assim resultado inédito na literatura para modelos ondulados bi-dimensionais. As visualizações de óleo evidenciaram dois mecanismos de controle de escoamento desencadeadas pelo escoamento secundário: bolhas de separação laminar tridimensionais e estruturas vorticais. Os resultados confirmam alguns poucos estudos experimentais e numéricos anteriores relacionadas com bolhas tridimensionais, e apresenta pela primeira vez estas estruturas como um mecanismo muito eficiente de controle de escoamento em regime de pós-stall justificando o aumento de máxima sustentação para o menor número de Reynolds. Adicionalmente, foram identificadas duas estruturas de bolhas tridimensionais nomeados aqui como \"bolhas com pontas\" e \"bolhas alongadas\" que causam distintos efeitos no regime de pré-stall. Esta tese apresenta como resultado maior desempenho para aerofólios ondulados com menor espessura (NACA 0012) e/ou para condições de menor número de Reynolds (Re=50,000)mostrando claramente que estas características levam as ondulações a operarem em condições de stall de bordo de ataque assim tendo um desempenho superior. Portanto, um espaço de projeto para tubérculos conduz às características de stall de bordo de ataque confirmando a suposição de Stanway (2008) oitos anos antes.

This diploma thesis deals with the analysis of the evaluation of public contracts according to economic benefits according to the Building Act No. 134/2016 Coll., On the award of public contracts. The theoretical part defines the basic concepts in the field of public procurement. The practical part deals with case studies related to the evaluation and description of evaluation criteria of public contracts awarded by the Desin&Build method.

The Design/Bid/Build (DBB) delivery method has historically been the most popular and the most effective means of determining the least cost for building a project based upon a set of construction documents. In recent years, however, other project delivery methods, including but limited to Construction Manager/General Contractor (CM/GC) and Design/Build (DB), have slowly taken a share of the construction market away from the DBB delivery method. The choice of delivery method that will produce the best value for an owner in the measurements of efficiency in quality, cost, and timeliness depends upon the type of project and the business culture of the project owner. A unique opportunity for a comparative study was presented by the Meetinghouse Facilities Department (MFD) of the Church of Jesus Christ of Latter-day Saints. The MFD completed over 200 repetitive meetinghouse projects in the U.S. over a five-year period (1999-2003), contracting approximately two-thirds of the projects using a CM/GC delivery method with an attached partnering agreement. The remaining meetinghouses were contracted using a DBB delivery method. A comprehensive comparison was conducted measuring all of the efficiencies created by the selection of delivery method, including short- and long-term costs, direct and indirect costs, construction cycle time, and quality assessment scores. After identifying and then adjusting for several confounding variables in the historical data, the statistical analysis provided evidence that the CM/GC delivery method proved to be the best value for the MFD by producing a total cost savings of over 5.5 percent on the meetinghouse projects when compared to the DBB meetinghouse projects. Construction cycle time was 20% shorter on the CM/GC meetinghouse projects and quality assessment (QA) scores were consistently higher. In regards to a 10-year life cycle repair costs, the CM/GC delivery method produced a higher quality meetinghouse, reducing repair costs by 34% when compared to the DBB meetinghouse projects.

國際上工程契約範本中多半就契約義務程度有所約定，國際諮詢工程師聯合會（Fédération Internationale Des Ingénieurs-Conseils, FIDIC）參照大英國協普通法上見解，於「生產設備及設計施工標準契約條款」與「設計採購施工/統包標準契約條款」等統包契約範本中，明文就統包承包商之設計義務採取合乎目的義務標準（fitness for purpose），亦即統包承包商應擔保工程完工時將合乎工程預期之使用目的。該義務標準不同於多數工程契約範本所採大英國協普通法專業服務契約一般適用的合理技術與謹慎(reasonable skill and care)標準，義務人須擔保一定結果之達成，乃無涉義務人業務執行行為有無過失之絕對義務，義務人不得以其已善盡專業注意義務或所需技術超乎科技水準為抗辯，亦不得主張業主就損害之發生或擴大與有過失而減輕賠償責任。而以契約明文約定適用合乎目的義務標準者，大英國協司法見解認為合乎目的義務標準將優先於遵照契約所定計畫或規範之義務，加以合乎目的義務難以取得保險保障，種種不利因素引起統包承包商之高度顧慮。 傳統設計後發包施作之工程契約模式下，大英國協普通法見解認為專業設計人員之契約默示義務標準與其他專業服務契約同為合理技術與謹慎義務，與統包承包商之設計工作默示適用合乎目的義務標準不同。本文由大英國協普通法案例觀察，相關見解差異與貨物買賣契約法律原則息息相關，並且受到當代法律經濟分析思維影響。然依本文之觀察，近年大英國協司法見解在合乎目的義務之默示適用及明示適用，似均出現避免適用該義務標準之案例，相關判決理由於大英國協司法見解之後續發展殊值觀察。 我國司法實務對統包工程契約之評價與大英國協普通法側重於不同契約特徵，而屬歐陸成文法系之我國法及德國法中，承攬人負有使完成工作無不適於通常或約定使用之瑕疵擔保責任，與大英國協普通法上合乎目的義務同為無過失責任。惟依本文觀察，歐陸法系之承攬人瑕疵擔保責任並不如大英國協普通法合乎目的義務嚴格，承攬人有較多減輕或免責事由可資主張，而我國司法實務見解下，承攬人免責之可能性又更高於德國法。 統包工程契約中之合乎目的義務約款並非獨立存在，其實質內涵仍需視各法域適用法律之具體內容而定。本文彙整比較統包工程契約設計工作之合乎目的義務於大英國協普通法系、歐陸成文法系之德國法及我國法之司法實務見解適用差異，期在相互參照之中，對各該司法見解提出評析建議，並供我國工程產業爭取海外標案時作為契約法律風險管理之參考。

Att nå effektivitet, en bra kostnadsbild och hantera den växande frågan gällande minskad belastning på miljön är viktiga delar i dagens byggprojekt. Att välja totalentreprenad som entreprenadform kan vara ett sätt att nå detta. För att bland annat hantera brister med denna entreprenadform kan man istället använda sig utav den relativt nya metoden ECI (Early Contractor Involvement). Metoden bygger på att få tillgång till entreprenörens kunskap tidigt och att gemensamt kunna angripa de utmaningar projektet står inför. Detta ställer höga krav på relationen mellan parterna. Syftet med denna studie uppnås först genom att visa att tidigare studier konstaterar att ECI bidrar gällande aspekterna effektivitet, kostnadsbild och i viss mån även till miljö- och hållbarhetsarbete, att fördelsfaktorerna överträffar nackdelsfaktorerna och att metoden är att föredra kontra en traditionell totalentreprenad. Sedan genom en surveystudie med en webbaserad enkätundersökning hos beställare, entreprenörer och projektörer/byggledare på en SME-byggentreprenörs (små och medelstora företag) marknad baserad i Stockholm. Här erhölls information om att ECI i det stora hela bidrar väldigt väl i aspekter kopplade till effektivitet och kostnadsbild och väl gällande miljö- och hållbarhetsfrågor kontra en traditionell totalentreprenad. Även information om att fördelsfaktorerna överträffar nackdelsfaktorerna på marknaden erhölls här, vilket stämmer överens med tidigare studier. Det kunde även konstateras att relationsbaserade faktorer är oerhört viktiga i ECI. Implementeringen och skapandet av ett gemensamt engagemang med tydliga ramar framhävs i de rekommendationer för ECI som lämnas i slutet. / Achieving efficiency, a satisfactory project cost and dealing with the growing issue of reduced impact on the environment are important parts of today's construction projects. Choosing design and build contract (D&B) in your project can be a way to achieve this. A way to manage shortcomings with this form of contract, you can instead use the relatively new method ECI (Early Contractor Involvement). The method is based on gaining access to the entrepreneur's knowledge early on and being able to jointly tackle the challenges the project faces. This places high demands on the relationship between the parties. The purpose of this study is first achieved by showing that previous studies state that ECI contributes in terms of efficiency, project cost and to some extent also to environmental and sustainability work, that the benefit factors outweigh the disadvantage factors and that the method is preferable to a traditional D&B-contract. Then through a survey study with a web-based survey of clients, contractors and designers/construction managers at a SME-construction company’s market (Small and Medium Enterprises) based in Stockholm. Here, information was obtained that ECI, overall, contributes very well in aspects related to efficiency and project cost and well regarded environmental and sustainability issues versus a traditional D&B-contract. Information showed that the advantage factors exceed the disadvantage factors on the market, which is then consistent with previous studies. It could also be stated that relationship-based factors are extremely important in ECI. The implementation and creation of a joint commitment with a clear framework is emphasized in the recommendations for ECI that are provided at the end.