Mühendislik Fakültesi / Faculty of Engineering
Permanent URI for this communityhttps://hdl.handle.net/11413/11
Browse
Browsing Mühendislik Fakültesi / Faculty of Engineering by Publisher "ASCE-AMER SOC CIVIL ENGINEERS, 1801 ALEXANDER BELL DR, RESTON, VA 20191-4400 USA"
Now showing 1 - 6 of 6
- Results Per Page
- Sort Options
Publication Behavior and design of seam-welded stainless steel circular hollow section flexural members(ASCE-AMER SOC CIVIL ENGINEERS, 1801 ALEXANDER BELL DR, RESTON, VA 20191-4400 USA, 2007-12) Kıymaz, Güven; Coşkun, Erdal; Coşgun, C.; TR141170; TR141151In an experimental study, a series of tests was per-formed on seam-welded structural stainless steel circular hollow sections (CHS) subjected to bending. The test program included various cross section geometries of CHS that covered a range of structural responses. Three-dimensional nonlinear finite-element (FE) models (ABAQUS) were established and verified with the experimental results accounting for material nonlinearity and manufacturing distortions. Close agreement was achieved between the test and finite-element analysis results in terms of load-deformation response and ultimate strength. The test and finite-element strength results with additional FE results generated for CHS models not considered in the test are compared with the strengths predicted using the American, Australian. and European specifications for cold-formed stainless steel structures. In light of the experimental/numerical results and code recommendations, strength and cross section classification criteria for stainless steel circular hollow section members in bending were examined. The results showed that significant improvements are possible for cross section slenderness limits provided by the current specifications.Publication Case Study: Izmit Domestic and Industrial Water Supply Build-Operate-Transfer Project(ASCE-AMER SOC CIVIL ENGINEERS, 1801 ALEXANDER BELL DR, RESTON, VA 20191-4400 USA, 2004-06) Şentürk, H. A.; Kaplanoğlu, S. B.; YAZICI, GÖKHANThe "build, operate, and transfer model" (BOT) is a financing model, which is used in many developing countries to finance new infrastructure projects with private sector participation. The BOT method foresees the financing, designing, building, operating, and managing of the facility by the private sector and then its transfer free of charge, to the owner after a predetermined concession period. For interested parties, the history of BOT laws and projects in Turkey is presented as an Appendix. In this study, the Izmit Domestic and Industrial Water Supply Project, the biggest privately financed water Supply project procured under the BOT model in the world at the time and the first in Turkey will be introduced and the problems that arose during the implementation of the project, namely, the scope of the project, equity debt ratio, return on equity, principles of accounting, coordination of State departments, land access, determination of the optimum operation period, and the sale price of the water, will be presented and suggestions will be given on how to deal with these problems.Publication Corrosion of Reinforcement in Relation to Presence of Defects at the Interface Between Steel and Concrete(ASCE-AMER SOC CIVIL ENGINEERS, 1801 ALEXANDER BELL DR, RESTON, VA 20191-4400 USA, 2005-08) Söylev, Tayfun Altuğ; Francois, R.In this study, steel-concrete interface defects were analyzed in order to define their potential to induce corrosion. Various types of steel-concrete interface defects were classified into two main groups: macrodefects and microdefects. Gaps formed beneath horizontal reinforcement as a result of bleeding and settlement of fresh concrete were analyzed for macrodefects. Microdefects presented no signs that could be identified by visual inspection and resulted not only from controlled pull-out of the steel bar but also from bleeding and settlement (but without the production of macrodefects as found with gap formation), Apart from interface defects, cover concrete porosity was defined as an intrinsic defect. The effect of these defects on reinforcement corrosion was investigated. Macrodefects have a direct effect on corrosion, whereas microdefects have no significant effect on Corrosion. Where the level of intrinsic defects was high, these had a greater effect on corrosion than interface macrodefects. The behaviors of conventional and self-compacting concrete (SCC) were compared. SCC was found to have better interface quality.Publication Diagnosis of the transition from rock soil in a granodiorite(ASCE-AMER SOC CIVIL ENGINEERS, 1801 ALEXANDER BELL DR, RESTON, VA 20191-4400 USA, 2004-09) AREL, ERSİN; ÖNALP, AKINThis paper describes an attempt to develop a method to define when granodiorite loses its properties as a rock and transforms into soil material. The research program approached the problem from a mechanistic point of view by comparing the pore water pressures generated during isotropic compression with the apparent-and micro-porosities, in terms of a newly proposed pore size distribution index as well as the compressive strengths of the specimens tested. A site was selected for study where weathering of the rock is not accompanied by the production of clay minerals, thus eliminating the complications introduced by the presence of highly compressive zones in the matrix. Samples tested using various criteria indicated that changes in the pore-size distribution can realistically reflect the transformation sought. It appears that further studies should be directed towards determination of the changes in the pore geometry, whereby a scientific definition of the transformation from rock to soil can be made.Publication Principal Components Regression of Onboard Sound Intensity Levels(ASCE-AMER SOC CIVIL ENGINEERS, 1801 ALEXANDER BELL DR, RESTON, VA 20191-4400 USA, 2008-11) Öngel, Aybike; Kohler, Erwin; Harvey, John; TR106042Roadways paved with open graded asphalt mixes typically generate lower traffic noise levels as compared to other types of pavements. A program was initiated in 2005 in California to evaluate the effectiveness of noise reducing surfaces over time and the pavement characteristics affecting those noise levels. In this study, tire/pavement noise was measured using the onboard sound intensity method. Data were collected on four different types of mixes: conventional open graded asphalt concrete, rubberized asphalt concrete that are open graded, rubberized asphalt concrete that are gap graded, and dense graded asphalt concrete mixes. A total of 72 field pavement sections that were at that time less than 8 years old were included in the study. Various pavement characteristics were measured and their effects on noise levels were evaluated using principal components regression, in addition to ordinary least-squares regression. This research confirmed that open graded pavements exhibit reduced tire noise compared to dense and gap graded mixes and quantified this reduction for typical mixes in California.Publication Subsurface characterization at ground failure sites in adapazari, Turkey(ASCE-AMER SOC CIVIL ENGINEERS, 1801 ALEXANDER BELL DR, RESTON, VA 20191-4400 USA, 2004-07) Bray, J. D.; Sancio, R. B.; Durgunoğlu, T.; Youd, T. L.; Stewart, J. P.; Seed, R. B.; Çetin, O. K.; Baturay, M. B.; Christensen, C.; Karadayılar, T.; ÖNALP, AKINGround failure in Adapazari, Turkey during the 1999 Kocaeli earthquake was severe. Hundreds of structures settled, slid, tilted. and collapsed due in pail to liquefaction and ground softening. Ground failure was more severe adjacent to and under buildings. The soils that led to severe building damage were generally low plasticity silts. In this paper, the results of a comprehensive investigation of the soils of Adapazari, which included cone penetration test (CPT) profiles followed by borings with standard penetration tests (SPTs) and soil index tests, are presented. The effects Of Subsurface conditions on the Occurrence of ground failure and its resulting effect on building performance are explored through representative case histories. CPT- and SPT-based liquefaction triggering procedures adequately identified soils that liquefied if the clay-size criterion of the Chinese criteria was disregarded. The CPT was able to identify thin seams of loose liquefiable silt. and the SPT (with retrieved samples) allowed for reliable evaluation of the liquefaction Susceptibility of fine-grained soils. A well-documented database of in situ and index testing is now available for incorporating in future CPT- and SPT-based liquefaction triggering correlations.