Every business involves risk, but due to its nature, construction business involves more risk than many other industries. Therefore, risk assessment is indispensable to the success of construction companies in terms of, preventing dramatic financial losses. When the decision process for expanding the operations in the international construction market is concerned, it becomes more important for companies to analyze the risk of the target country. For this reason, construction firms benefit from many different risk assessment methods. Contractors prevalent practice of risk assessment is identifying related risks and making an evaluation relying on their personal judgments (without substantial explicit support), but none of the applied methods is construction specific. To overcome this, a construction specific country Risk Breakdown Structure (RBS) is prepared. While preparing this construction specific RBS, not only macro level country risks but also market risks for construction are considered in order to reflect the real risks of performing construction business in foreign countries. Consequently, a tentative country RBS specific for construction industry is constructed and its reliability is tested by interviews carried out with six professionals from four Turkish construction companies operating in international markets. After finalization of the RBS, utilization method of practical aspects of RBS is questioned by interviewing the experts. Finally, a case study is conducted to propose a company-specific system for iv the implementation of RBS. The case study findings demonstrate the applicability of RBS and its potential as a systematic country risk assessment tool.

Historic towns and historic buildings are important witnesses of the past cultures and civilizations. Their sustainability and transfer to the next generations require continuous maintenance and repair interventions which should be compatible with their original construction techniques, details and materials. In order to define proper interventions to a historic building, it is necessary to understand how and from what it is built. Therefore, traditional construction materials, detailings and techniques should be well understood prior to any kind of intervention to a historic building. The objective of this study is, first of all, to provide a body of knowledge on traditional construction process and techniques / then, to store, structure, process, represent and share this knowledge in a systematic and controlled way by means of a web based GIS portal. In this respect, traditional timber framed houses of Tarakli in Sakarya has been chosen as the case study, on account of being one of the significant historical towns in our country where the tissue together with historical building is still conserved. For this study, among the applications of GIS technology, Web-based GIS has been determined as the most effective and functional tool in order to develop an online information portal for storing, displaying the collected raw data and sharing with other users as utilizable information.

The duration of construction of a project depends on many factors, such as: cost, location, site characteristics, procurement methods, area of construction, footprint of the building and its height, etc. It is very important to be able to predict these durations accurately in order to successfully complete a project on time. Various construction duration estimation tools have been developed to make accurate predictions, as &ldquo / time is money.&rdquo / The main objective of this study was to develop a model that can be used to predict the construction duration of a project in a reliable and practical way. Contractors can thus use a project&#039 / s characteristics, as given in the tender documents, to estimate the actual amount time it would take them to complete the construction works. In this study, factors affecting the duration of a construction project and models for estimating construction durations were investigated. Within this framework, duration estimation models such as / Bromilow&rsquo / s Time-Cost (BTC) Model and Building Cost Information Service (BCIS) Model were used while Simple Linear Regression (SLR) and Multiple Linear Regression (MLR) analyses were conducted on data related to seven case study buildings that are situated at the Middle East Technical University (METU) campus in Ankara. This data was obtained from the Department of Construction and Technical Works (DCTW) at METU. The closeness in estimation of the regression analyses was investigated and finally an MLR model was obtained which was based on two parameters / the area of the building and the area of its fa&ccedil / ade. On the other hand, as opposed to studies reported in literature, the effect of cost on duration was not seen to be significant.

In the production of cement, to increase the cement/clinker ratio and decrease CO2 emission, the most important alternative is to produce mineral admixture incorporated cements (CEM II-III-IV-V) instead of portland cement (CEM I). These cements are usually produced by intergrinding the portland cement clinker and the mineral admixtures. However, the difference between grindabilities of the different components of such cements may cause significant effects on the particle size distribution and many other properties. For this reason, separate grinding of additives and clinker may be thought as an alternative. In this study, the effects of intergrinding and separate grinding on the particle size distribution and consequently on the strength of portland composite cements which contained natural pozzolan (trass), granulated blast furnace slag (GBFS) and limestone besides portland cement clinker were studied.

Acoustic design of shopping malls which have become very popular in recent years, has gained importance and it has been considered as an integral part of the design &ndash / construction and life cycle treatment of such complex &ndash / functional buildings. In this study, acoustic qualities of shopping malls are to be inquired by focusing on circulation areas and atrium spaces where noise is one of major disturbances. In this context, first taxonomy of shopping malls regarding their geometrical forms is to be proposed together with plan layouts, construction materials and spatial organizations. Then some of these malls in representing major characteristics of the each class in the taxonomy are to be acoustically analyzed and compared with standards by aiming to provide some guiding principles for acoustical design of such spaces.

Although performance based assessment procedures are mainly developed for reinforced concrete and steel buildings, URM buildings occupy significant portion of building stock in earthquake prone areas of the world as well as in Turkey. Variability of material properties, non-engineered nature of the construction and difficulties in structural analysis of perforated walls make analysis of URM buildings challenging. Despite sophisticated finite element models satisfy the modeling requirements, extensive experimental data for definition of material behavior and high computational resources are needed. Recently, nonlinear equivalent frame models which are developed assigning lumped plastic hinges to isotropic and homogenous equivalent frame elements are used for nonlinear modeling of URM buildings. The work presented in this thesis is about performance assessment of unreinforced brick masonry buildings in Turkey through nonlinear equivalent frame modeling technique. Reliability of the proposed model is tested with a reversed cyclic experiment conducted on a full scale, two-story URM building at the University of Pavia and a dynamic shake table test on a half scale, two story URM building at the Ismes Laboratory at Bergamo. Good agreement between numerical and experimental results is found. Finally, pushover and nonlinear time history analyses of three unreinforced brick masonry buildings which are damaged in 1995 earthquake of Dinar is conducted using the proposed three dimensional nonlinear equivalent model. After displacement demands of the buildings are determined utilizing Turkish Earthquake Code 2007, performance based assessment of the buildings are done.

This thesis analyses tha impact of the Xinjiang Problem on the foreign policy of China. Because of its strategic location and natural resources, Xinjiang Uyghur Autonomous Region has great importance for China. this thesis argues that Chinese foreign policy towards Central Asian region has been shaped by security considerations of China related to the Xinjiang Problem. the Xinjiang Problem shapes China&#039 / s foreign relaitons wsth Central Asian States, Russia, the U.S. and Turkey becouse this problem has became important element of China&#039 / s territorial integrity as well ass its strategy of stabilizing Central Asian region.

Isolator displacements, floor accelerations, roof displacements, base shear and torsional moments are basic parameters that are considered in the design of seismically isolated structures. The aim of this study is to evaluate the effects of bidirectional earthquake excitations of near fault records on the response of base isolated structures in terms of basic parameters mentioned above. These parameters computed from nonlinear response history analysis (RHA) and they are compared with the parameters computed from equivalent lateral force procedure (ELF). Effect of asymmetry in superstructure is also examined considering mass eccentricity at each floor level. Torsional amplifications in isolator displacements, floor accelerations, roof displacements and base shear are compared for different level of eccentricities. Two buildings with different story heights are used in the analyses.The building systems are modeled in structural analysis program SAP2000. The scaling of ground motion data are taken from the study of &ldquo / Response of Isolated Structures Under Bi-directional Excitations of Near-fault ground Motions&rdquo / (Ozdemir, 2010). Each ground motion set (fault normal and fault parallel) are applied simultaneously for different range of effective damping of lead rubber bearing (LRB) and for different isolation periods.

La question du rôle structural et de la signification géodynamique des grandes discontinuités dans les<br />phénomènes tardi-orogéniques se pose dans la chaîne Varisque. Dans le Massif central français, le Sillon Houiller (SH)<br />est une faille lithosphérique dont la cinématique et le fonctionnement anté-Stéphanien restent inconnus. Afin de mieux<br />appréhender le rôle du SH au cours de l' évolution post-orogénique du Massif central, une étude pluridisciplinaire a été<br />réalisée sur des massifs granitiques qui longeaient l' accident : analyses pétro-structurales, géochrono-logiques,<br />anisotropie de la susceptibilité magnétique (ASM), gravimétrie ainsi que le retraitement de données aéro-magnétiques<br />disponibles. Ces nouvelles données géophysiques, de terrain et de l'ASM, ont été intégrées dans des modélisations<br />géophysiques et géologiques, 2D et 3D, directes et inverses qui ont mis en valeur la géométrie et la mise en place de ces<br />plutons syn-tectoniques namuriens. Il apparaît qu' au Namurien, le SH peut être lié à la mise en place de magmas,<br />comme le pluton de Montmarault, ou pas, comme ceux de Glénat, Omps et Boisset. Néanmoins, au Namurien,<br />l' ensemble des plutons granitiques enregistre une linéation d' étirement NW-SE, perpendiculaire à l' orientation générale<br />du SH. Au vu des analyses structurales et cinématiques, au Namurien, le SH s' il existe, ne peut alors que se comporter<br />que comme une zone de dilatation NW-SE.

This thesis contributes to increased knowledge on Holocene climate and environmental variability from two complex and sparsely studied areas. Using a speleothem from Gasparee Cave, Trinidad, as a paleoclimate archive, the local expression of the 8.2 ka (thousand years before 1950) climate event and associated patterns of the inter-tropical convergence zone (ITCZ) and rainfall is provided. Subsequent speleothem studies using multi-proxy analysis of stalagmites from Kapsia Cave and Alepotrypa Cave, Greece, provide records of climate, vegetation and human induced changes in the cave environment during parts of the Holocene. The speleothems from the well-studied Neolithic habitation site, Alepotrypa Cave, have produced a climate and habitation record which covers the period of 6.3-1.0 ka. The cave was inhabited between 8.0-5.2 ka and was closed by a tectonic event, which has preserved the settlement. The stable oxygen record shows the first well-dated and robust expression of the 4.2 ka dry event in the Peloponnese, places the timing of the 3.2 ka dry event within an ongoing dry period, and shows a final dry event at 1.6 ka. The North Atlantic as well as more regional drivers, such as the North Sea Caspian Pattern Index is proposed to, in a complex interplay, govern many of the climate trends and events observed. Trace element variation after the site is abandoned indicate what is interpreted as two volcanic eruptions, the Minoan eruption of Thera (Santorini) around 3.6 ka and the 2.7 ka eruption of Somma (Vesuvius). Variations in trace elements during the habitation period show clear human influence, indicating an association with specific cave activities. One of the most interesting prospects for continued work on Alepotrypa Cave is this successful marriage of speleothem studies and archeology. A framework of dates which constrain some behavior of people living in the cave is only the beginning, and there is great potential to continue finding new clues in the speleothem data. / Denna avhandling bidrar till ökad kunskap om klimatets variationer och miljön i två geografiskt skilda områden på låga breddgrader och under tidsperioder inom den Holocena epoken. Genom att använda en droppsten (stalagmit) från Gasparee-grottan, Trinidad, som ett paleoklimatarkiv, har det bland annat varit möjligt att visa att Trinidad upplevde torrare förhållanden under den snabba klimatförändring som observerats ske för 8200 år sedan på många platser i världen. Denna torrare klimatsituation i Trinidad föreslås vara ett resultat av en sydlig förflyttning av den intertropiska konvergenszonen. Övriga stalagmiter som studerats för denna avhandling kommer från Kapsia-grottan och Alepotrypa-grottan som finns på Peloponnesos-halvön i Grekland. Resultaten därifrån speglar dels klimat- och vegetationsvariatoner och dels graden av mänsklig aktivitet, under tiden för ca 8000 år sedan till för 1000 år sedan. Alepotrypa-grottan är känd för att vara en av de större Neolitiska boplatserna i Grekland. Isotop- och spårämnesanalyser av stalagmiterna har bidragit med ny kunskap om tidpunkten för mänsklig aktivitet, hur människorna påverkade grott-miljön samt hur klimatet varierat efter det att grottan, genom en tektonisk händelse, stängdes för människans inverkan. Snabba klimatförändringar, för 4200 och 3200 år sedan, observerade i andra regioner, rekonstrueras här för första gången på Peloponnesos. En snabb förändring mot torrare förhållanden observeras även för 1600 år sedan. De klimatstyrande processerna föreslås vara en kombination av storskaliga processer som den nordatlantiska oscillationen och mer regionala processer som det så kallade North Sea Caspian Pattern Index. Variationer i spårämnen i stalagmiterna efter att Alepotrypa-grottan stängdes kan kopplas till två vulkaniska utbrott, nämligen det Minoiska utbrottet av Thera på ön Santorini kring 3600 år sedan och utbrottet av Somma (Vesuvius) kring 2700 år sedan. Spårämnesvariationer under bo-perioden ger tydliga indikationer på människans påverkan på grottmiljön och som delvis kan länkas till specifika aktiviteter, som eldning av dynga i grottan. Avhandlingen är ett resultat av en framgångsrik kombination av klimatstudier och arkeologisk kunskap och utgör ett viktigt underlag för fördjupat interdisciplinärt forskningssamarbete i Alepotrypa-grottan. / <p>At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 1: Manuscript. Paper 4: Manuscript. Paper 5: Manuscript. Paper 6: Manuscript.</p>