WoS İndeksli Yayınlar Koleksiyonu / WoS Indexed Publications Collection
Permanent URI for this collectionhttps://hdl.handle.net/11147/7150
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Article Citation - WoS: 2Citation - Scopus: 3Site Assessment of Surface Texture and Skid Resistance by Varying the Grit Parameters of an Sma(American Society of Civil Engineers (ASCE), 2022) Gökalp, İslam; Uz, Volkan Emre; Saltan, Mehmet; Tepe, Mehtap; 03.03. Department of Civil Engineering; 03. Faculty of Engineering; 01. Izmir Institute of TechnologyFor the sale operation of vehicles, pavement should provide adequate skid resistance, which can be achieved by using high polishing-resistant aggregate in wearing courses. However, supplying high-quality aggregate is not always feasible due to high transportation costs. For this reason, a method called gritting was adapted to meet the Highway Technical Specification (HTS) of Turkey in 2013. According to the method, for certain parts of the country, the wearing course can be constructed with local aggregates that have minimum polished stone value (PSV) of 40 (PSV >= 40), but, in this case, the surface must be covered with a high polishing-resistant aggregate (PSV >= 50), after the rollers' first pass. The objective of this study was to improve the present gritting method by investigating the effect of grit parameters on pavement performance under real traffic conditions. In this regard, during its construction, the wearing course of 0-51 Highway was gritted with different aggregate types (slags and natural), sizes (1-3; 1-5 mm), spreading amount (1.5; 2; 2.5 kg/m(2)), and spreading time (before and after the first pass of a roller) on eight test sections. Then, the macrotexture and skid resistance performance of these sections were evaluated under real traffic and environmental conditions for longer than 4 years. Changes in surface texture and skid resistance with respect to traffic were determined for each section. The results showed that higher skid resistance values were obtained at the sections gritted with metallurgical slags. Additionally, the sections gritted with 1-5 mm aggregates had better skid resistance than those gritted with 1-3 mm, while the change in mean texture depths were not very significant.Article Closure To "reverse Flood Routing in Rivers Using Linear and Nonlinear Muskingum Models" by Meisam Badfar, Reza Barati, Emrah Dogan, and Gokmen Tayfur(American Society of Civil Engineers (ASCE), 2022) Badfar, Meisam; Tayfur, Gökmen; Doğan, Emrah; Tayfur, Gökmen; 03.03. Department of Civil Engineering; 03. Faculty of Engineering; 01. Izmir Institute of TechnologyArticle Citation - WoS: 10Citation - Scopus: 10Effects of Mixture Design Parameters on the Mechanical Behavior of High-Performance Fiber-Reinforced Concretes(American Society of Civil Engineers (ASCE), 2020) Erdem, Tahir Kemal; Erdem, Tahir Kemal; Demirhan, Serhat; Yıldırım, Gürkan; Banyhussan, Qais S.; Şahin, Oğuzhan; Balav, Mohammad H.; Şahmaran, Mustafa; 03.03. Department of Civil Engineering; 03. Faculty of Engineering; 01. Izmir Institute of TechnologyThe main purpose of this research is to assess the influence of different design parameters on the mechanical performance of high-performance fiber-reinforced concrete (HPFRC) mixtures. Special attention is also paid to achieving deflection-hardening behavior in the presence of a large amount of coarse aggregates. Different mixture design parameters were the initial curing ages (3, 7, 28, and 90 days), ratios of Class F fly ash (FA) to portland cement (PC) (0.0, 0.2, and 0.4), addition/type of nanomaterials [nanosilica (NS), nanoalumina (NA), and nanocalcite (NC)], and combinations of fibers [polyvinyl-alcohol + steel (P, S) or brass-coated microsteel + steel (B, S)]. The experimental program included the evaluation of compressive strength, flexural strength, and midspan deflection results in addition to test parameters recorded under biaxial flexural loading via a series of square panel tests, including peak load and energy absorption capacities. Test results revealed that deflection-hardening response coupled with multiple microcracks can be obtained when large amounts of coarse aggregates are available for all HPFRC mixtures. As expected, experimental results change depending on the different curing ages and FA/PC ratios. The most distinctive parameters affecting the results are addition/type of nanomaterials and the presence of different fiber combinations. In the presence of nanomaterials, all results from the different tests improved, especially for NA and NS inclusions. With slight concessions in flexural deflection results, B fiber is shown to be a successful candidate to fully replace costly P fibers because most properties of B, S fiber-reinforced HPFRC mixtures outperformed those with P, S fibers, both under four-point bending and biaxial flexural loading.Article Construction Techniques of Hayat Houses: Two Case Studies in the Vicinity of Izmir(American Society of Civil Engineers (ASCE), 2019) Turan, Mine; Hamamcıoğlu Turan, Mine; Aktaş, Engin; Aktaş, Engin; Mamaklı, Fatma Sezgi; Kaplan, Zişan; 02.01. Department of Conservation and Restoration of Cultural Heritage; 03.03. Department of Civil Engineering; 03. Faculty of Engineering; 01. Izmir Institute of Technology; 02. Faculty of ArchitectureThis study aims to contribute to the analytic studies on constructional aspects of the hayat house typology with an eye on its historical evolution for conservation purposes. The method used included a review of the surviving examples of the typology in Izmir and its vicinity and the selection of two intact examples whose structural components are legible: one from the earliest period and the other from the latest period. The examples selected are Kerimaga Konagi in Birgi, odemis, Izmir and a house in Kirkagac, Soma, Manisa. The early example (probably eighteenth century, constructed over the remains of an older house) sustains the traditional box system in its wooden upper story that integrates with the roof. The provision of level differences on the upper floor, the traditional relationship of the sitting level-window design, and masonry base are its authentic features. The late example (probably early twentieth century) presents signs of modernization, such as the establishment of a systematic wooden roof and wall frames in relation to each other, lack of diagonals in the perpendicular wall frame, avoidance of projections, and relatively elongated windows placed at higher positions.Article Citation - WoS: 6Citation - Scopus: 4Conservation-Aimed Evaluation of a Historical Aqueduct in Izmir(American Society of Civil Engineers (ASCE), 2019) Mamaklı, Fatma Sezgi; Turan, Mine; Hamamcıoğlu Turan, Mine; Vardaroğlu, Mustafa; Aktaş, Engin; 02.01. Department of Conservation and Restoration of Cultural Heritage; 03.03. Department of Civil Engineering; 03. Faculty of Engineering; 01. Izmir Institute of Technology; 02. Faculty of ArchitectureThe seventeenth century was the era in which Izmir became an international commercial center in the eastern Mediterranean. The vizier of the era, Koprulu Fazil Ahmet Pasa, noticed the scarcity of potable water in relation with the increasing population at the center of this harbor city and ordered the construction of an aqueduct on Melez Valley. The Veziraga Aqueduct was constructed in 1674. This article aims to identify historical, architectural, and structural characteristics of the Veziraga Aqueduct so that its heritage values and conservations problems can be understood. The geographical and historical characteristics of the Veziraga Aqueduct are described by taking the effects of site and the sociocultural situation of city into consideration. The architectural characteristics of the aqueduct are prepared by using the site survey data to reveal the current condition and find out the original state. Seismic behavior of the aqueduct is investigated by using two approaches: analytical equivalent static analysis and finite-element analysis. The historical, architectural, and structural characteristics of the Veziraga Aqueduct prove its historical, documentary, and aesthetic values.Article Citation - WoS: 17Citation - Scopus: 18Linear Wave Interaction With a Vertical Cylinder of Arbitrary Cross Section: an Asymptotic Approach(American Society of Civil Engineers (ASCE), 2017) Dişibüyük, Nazile Buğurcan; Yılmaz, Oğuz; Yılmaz, Oğuz; 04.02. Department of Mathematics; 04. Faculty of Science; 01. Izmir Institute of TechnologyAn asymptotic approach to the linear problem of regular water waves interacting with a vertical cylinder of an arbitrary cross section is presented. The incident regular wave was one-dimensional, water was of finite depth, and the rigid cylinder extended from the bottom to the water surface. The nondimensional maximum deviation of the cylinder cross section from a circular one plays the role of a small parameter of the problem. A fifth-order asymptotic solution of the problem was obtained. The problems at each order were solved by the Fourier method. It is shown that the first-order velocity potential is a linear function of the Fourier coefficients of the shape function of the cylinder, the second-order velocity potential is a quadratic function of these coefficients, and so on. The hydrodynamic forces acting on the cylinder and the water surface elevations on the cylinder are presented. The present asymptotic results show good agreement with numerical and experimental results of previous investigations. Long-wave approximation of the hydrodynamic forces was derived and used for validation of the asymptotic solutions. The obtained values of the forces are exact in the limit of zero wave numbers within the linear wave theory. An advantage of the present approach compared with the numerical solution of the problem by an integral equation method is that it provides the forces and the diffracted wave field in terms of the coefficients of the Fourier series of the deviation of the cylinder shape from the circular one. The resulting asymptotic formula can be used for optimization of the cylinder shape in terms of the wave loads and diffracted wave fields.Article Citation - WoS: 4Citation - Scopus: 5Importance of Static Correction and Damping in the Analysis of a Cable-Stayed Bridge Subjected To Displacement Loading(American Society of Civil Engineers (ASCE), 2017) Hızal, Çağlayan; Turan, Gürsoy; Turan, Gürsoy; Hızal, Çağlayan; 03.03. Department of Civil Engineering; 03. Faculty of Engineering; 01. Izmir Institute of TechnologyCable-stayed bridges with long spans are excited by different support vibrations on both sides of the main span. Therefore, a realistic seismic structural analysis of the bridge must involve multiple-support excitation. The dynamic equation of motion, in which all degrees of freedom are solved at once, can be solved directly. A modal analysis might also be possible, but care must be taken with the number of modes used in the analysis. If the ground motion is described in terms of displacement and velocity, which is referred to as displacement loading, then a static correction that will account for the unconsidered higher modes must be performed. In this study, the procedure of multiple-support excitation through the use of modal transformation is explained in detail. The effects of changes in damping levels that affect the analysis results are investigated by using the static correction method in displacement loading. An example is given to illustrate the mentioned problem by using a finite-element model of the cable-stayed Bill Emerson Memorial Bridge.Article Citation - WoS: 1Citation - Scopus: 3Strength Requirements for Shear Diaphragms Used for Stability Bracing of Steel Beams(American Society of Civil Engineers (ASCE), 2017) Eğilmez, Oğuz Özgür; Vardaroğlu, Mustafa; Eğilmez, Oğuz Özgür; 03.03. Department of Civil Engineering; 03. Faculty of Engineering; 01. Izmir Institute of TechnologyLight-gauge metal sheeting is often used in steel building and bridge industries as concrete deck formwork. Besides providing support to the fresh concrete, the sheeting acts as a shear diaphragm and provides continuous lateral bracing to the top flanges of the beams to which they are attached. An adequate stability-bracing system must possess sufficient stiffness and strength to control deformations and brace forces. Strength requirements for shear diaphragms are currently not well established. A computational study was conducted to develop strength requirements for shear diaphragms bracing simply supported steel beams. Both end-fastener and sidelap-fastener connections were modeled in the study. To the best of the authors' knowledge, this is the first study to quantify the stability-induced forces in sidelap fasteners. The effects of deck width and number of end and sidelap fasteners on brace forces were investigated. Expressions were developed to estimate the stability-induced brace forces in end-fastener and sidelap-fastener connections.Article Citation - WoS: 65Citation - Scopus: 81Assessing Coordination Performance Based on Centrality in an E-Mail Communication Network(American Society of Civil Engineers (ASCE), 2015) Doğan, Sevgi Zeynep; Arditi, David; Doğan, Sevgi Zeynep; Erbaşaranoğlu, Bengi; 02.02. Department of Architecture; 02. Faculty of Architecture; 01. Izmir Institute of TechnologyBuilding design and construction require the collective effort of diverse project participants. The coordination performance of these project participants is important for effective management and needs to be assessed periodically. However, there is no uncomplicated quantitative way to measure coordination. Measuring coordination is cumbersome and time-consuming particularly during the project execution phase. This study proposes an easy procedure for monitoring the coordinative performance of project participants. The degree, betweenness, and closeness centrality measures of the project participants in a wayfinding signage project at a major airport construction project are calculated using social network analysis on the e-mail communication network between the participants. A centrality index is defined for each firm based on the average of these three centrality measures. The firm's coordination score is also calculated based on content analysis of the sent and received e-mails between the participants. The coordination scores are found to be highly correlated with the centrality indices. To define the coordinative role of a firm, its centrality index could therefore be measured easily using a simple software and only the number and direction of e-mails exchanged betweenArticle Citation - WoS: 46Citation - Scopus: 53Distorted Physical Model To Study Sudden Partial Dam Break Flows in an Urban Area(American Society of Civil Engineers (ASCE), 2014) Güney, Mehmet Şükrü; Tayfur, Gökmen; Tayfur, Gökmen; Elçi, Şebnem; 03.03. Department of Civil Engineering; 03. Faculty of Engineering; 01. Izmir Institute of TechnologyA distorted physical model, based on Ürkmez Dam in Izmir, Turkey, was built to study sudden partial dam break flows. The distorted model had a horizontal scale of 1/150 and a vertical scale of 1/30, containing dam reservoir, dam body, and downstream area-from dam body to Ürkmez urban area until the sea coast. In the model, the reservoir is approximately 12 m3, the dam body has a width of 2.84 m and a height of 1.07 m, and the downstream area is nearly 200 m2. The Ürkmez Dam was chosen because Ürkmez Town is located right at its downstream area, allowing the study of dam break flows in an urban area. Furthermore, the dimensions were suitable such that it allowed the construction of a physical model (dam reservoir, dam body, and downstream area) having a horizontal scale of 1/150 in the available space of 300 m2. The features creating roughness such as buildings, bridge, and roads were also reflected in the physical model. The dam break flow was investigated for sudden partial collapse, which was simulated by a trapezoidal breach on the dam body. The water depths at downstream area were measured at eight different locations by using e+ WATER L (level) sensors. The velocities were measured at four different locations by ultrasonic velocity profiler (UVP) transducers. The propagation of the flood was recorded by a high-defnition camera. The experimental results show that the Ürkmez area can be flooded in a matter of minutes, at depths reaching up to 3 m in residential areas in 4 min. The flood wave front can reach the residential areas in 2 min and to the sea coast in 4 min. Flow velocities can reach 70.9 km/h in sparse residential areas, close to dam body. Away from the dam body in the sparse buildings part of the town, the velocities can reach 27.7 km/h. In dense residential areas of the town, the velocities are too low (2.8 km/h) but flow depths can reach 3 m. Velocity profiles show similar behavior like unsteady and nonuniform open channel flow in nonresidential areas close to the dam body. In residential areas away from the dam body, the velocity profiles are more uniform, having lower velocity values. Vertical variations of velocities show markedly different behavior during rising and recession stages. The profiles are smooth during the rising stage in sparse residential area, yet it shows fluctuating behavior during the recession stage.