İnşaat Mühendisliği Bölümü Yayın Koleksiyonu
Permanent URI for this collectionhttps://hdl.handle.net/20.500.12416/395
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Article Liquefaction Hazard Assessment in a Gis Environment: a Case Study of Buğday Pazarı Neighborhood in Çankırı Province(Techno-press, 2024) Ozturk, Sevki; Sarifakioglu, Ender; Yurdakul, ErenSeismic movements have varying effects on structures based on characteristics of local site. During an earthquake, weak soils are susceptible to damage due to amplified wave amplitudes. Soil -structure interaction issue has garnered increased attention in T & uuml;rkiye, after devastating earthquakes in Kocaeli G & ouml;lc & uuml;k (1999), Izmir (2020), Kahramanmara Pazarc & imath;k and Elbistan (2023). Consequently, liquefaction potential has been investigated in detail for different regions of T & uuml;rkiye, mainly with available field test results. & Ccedil;ank & imath;r & imath;, a city located close to North Anatolian Fault, is mainly built on alluvium, which is prone to liquefaction. However, no study on liquefaction hazard has been conducted thus far. In this study, groundwater level map, SPT map, and liquefaction risk map have been generated using Geographical Information System (GIS) for the Bu & gbreve;day Pazar & imath; District of & Ccedil;ank & imath;r & imath; province. Site investigations studies previously performed for 47 parcels (76 boreholes) were used within the scope of this study. The liquefaction assessment was conducted using Seed and Idriss's (1971) simplified method and the visualization of areas susceptible to liquefaction risk has been accomplished. The results of this study have been compared with the City Council's precautionary map which is currently in use. As a result of this study, it is recommended that minimum depth of boreholes in the region should be at least 30m and adequate number of laboratory tests particularly in liquefiable areas should be performed. Another important recommendation for the region is that detailed investigation should be performed by local authorities since findings of this study differ from currently used precautionary map.Article Citation - WoS: 1Citation - Scopus: 1Experimental Study on the Interaction Between Bridge Pier and Abutment Concerning Clear-Water Local Scour(Springer int Publ Ag, 2023) Akbulut, Omer Faruk; Kokpinar, Mehmet Ali; Gogus, MustafaEstimation of scour depth around bridge piers and abutments is essential for safety and economic design in alluvial rivers. Although local scour around bridge piers and abutments has been studied separately by a large number of investigators, there is limited research on the literature related to the interaction between these two structures. Hence, in this study, the aim is to investigate the interaction between bridge abutments and pier scours in detail. For this reason, bridge abutments of different lengths of La = 0.05, 0.10, and 0.15 m and a pier with diameter of D = 0.1 m were placed at various distances from each other in a long sediment channel and tested under clear-water flow conditions with constant flow intensity. All the important dimensionless parameters involved in the interaction phenomenon were derived from theoretical analysis, and the relationships between them were investigated. Analysis of the data showed that the presence of a pier in the flow medium in addition to an abutment has a certain amount of influence on the formation of scour holes around the structures. The influence of the abutment on the pier was more noticeable in the current study, particularly for longer abutments, leading to average increases of up to 20% in scour depth around the pier. The study's findings revealed that the presence of both a pier and an abutment in the flow medium exerted a discernible, unfavorable influence on the development of scour holes, particularly around piers.Article Citation - WoS: 16Citation - Scopus: 17Flow Structure and Fish Passage Performance of a Brush-Type Fish Way: a Field Study in the Yidere River, Turkey(Csiro Publishing, 2019) Kucukali, Serhat; Verep, Bulent; Alp, Ahmet; Turan, Davut; Mutlu, Tanju; Kaya, Cuneyt; Ozelci, DursunThe fish passage performance and flow structure of a brush fish pass were investigated at the ncirli Small Hydropower Plant on the yidere River, located in the East Black Sea region of Turkey. The spatial distributions of velocity vectors, power velocity, Froude number and turbulent kinetic energy are presented. The flow is quasi-uniform and subcritical, which provides different migration corridors with favourable hydraulic conditions; importantly for the fish, these corridors continue through the complete fish pass. The flow-bristle interaction creates a reduced velocity and low-turbulence resting zones. In addition, the passage efficiency of the brush fish pass was assessed using passive integrated transponder telemetry. The results clearly showed that upstream passage efficiency differs between fish species: Salmo coruhensis performed better than Alburnoides fasciatus on the same fish passage. The passage efficiency for the target fish species S. coruhensis was calculated to be 82.4%. The data revealed that the brush fish passage provides passage for small-bodied fish (total body length <15 cm) in a high-gradient channel with a slope of 10%. The monitoring data revealed that bristles as flexible hydraulic elements are beneficial for migrating fish.Article Citation - WoS: 6Citation - Scopus: 8A Modified Applied Element Model for the Simulation of Plain Concrete Behaviour(Emerald Group Publishing Ltd, 2023) Soysal, Berat Feyza; Arici, Yalin; Tuncay, KaganA modified applied element model to simulate the behaviour of plain concrete continuum structures including discrete cracking is proposed in this study. In the classical applied element model, Poisson effects are fully ignored. To remediate this issue, diagonal elements are introduced to include the Poisson effect, and the constitutive parameters are rigorously determined using the Cauchy-Born rule and the hyper-elastic theory. The formulation is validated for linear elastic problems and the consistency and convergence behaviour of the numerical approach is shown. Tensile softening formulation using the concept of fracture energy is utilised for the nonlinear range. In this range, the approach is validated using the classical benchmark tests with pure tensile, split-tensile, combined shear-tensile and bending dominated push-over loading. The load-displacement behaviour and crack response were captured successfully, showing the proposed methodology can be used to quantify discrete cracks on large systems, such as dam monoliths, from initiation to significant damage levels.Article Citation - WoS: 3Citation - Scopus: 3Improved Equations for the Profile of a Vertical Air-Core Vortex(Korean Society of Civil Engineers-ksce, 2023) Yildirim, Nevzat; Tastan, KeremThe available formulas for the profile of a vertical non-air-entraining vortex are not practical because they involve unknown parameters and need measurements of the local viscous-core radii across the height of the air-core vortex. Also, these formulas can not be used for the air-entraining vortices. In the present study, the available formulas involving unknown parameters were further improved. Findings are as follows. 1) the magnitudes of the unknown parameters vary across the height of the profile of the air-core vortex and they are the function of the ratio of the height of the air-core vortex to the submergence of the intake; 2) simple charts and formulas were obtained for the variations of the unknown parameters for the air-core vortices with and without an intake; 3) in lieu of the local viscous-core radius, the radius at the half-depth of the profile of the air-core vortex was used; 4) no laborious work of measurements are needed to determine the local viscous-core radii along the profile of the vortex; and 5) the improved formulas are in good agreement with available test data for the profiles of both the non-air-entraining and the air-entraining vortices with or without a vertically flowing downward intake.Article Citation - WoS: 16Citation - Scopus: 16Novel Bond-Slip Model Between Concrete and Angular Cfrp Fan Type Anchoraged Cfrp Strip(Taylor & Francis Ltd, 2022) Ghoroubi, Rahim; Mercimek, Omer; Sakin, Shaimaa; Anil, OzgurOne of the most important design approaches in the repairing/strengthening details is using CFRP (Carbon Fiber Reinforced Polymer) to delay the debonding of the CFRP strips/plates from the surface to take full advantage of the CFRP reinforcement. Compared to non-anchored strips, research studies regarding bond-slip models developed for fan type CFRP anchors and anchored CFRP strips to strengthen details are limited in the related literature review. However, in studies on this subject, anchors are placed at 90 degrees to the axial tensile force applied to the CFRP strips. The ultimate load-bearing capacity and bond-slip models of CFRP strips with the different angled CFRP fan type anchor under axial tensile force have not been found in the literature review. Within the study's scope, 28 angled CFRP strip test specimens were produced and then tested under the effect of monotonically increasing axial tensile force with an experimental setup designed by the authors. The variables examined in this study were the concrete compressive power, the CFRP strip's width, the number of the CFRP anchor fan type, and the angle of the anchor placed on the CFRP strip. As a result of the study, an equation was proposed for calculating the ultimate load-bearing capacity of angled anchored CFRP strips and angled anchored CFRP strips. Finally, a new proposal for the bond-slip model was developed. It is thought that the new interface bond-slip model developed for CFRP strips with different angles will make an important contribution to the literature. It can be used in finite element analysis to realistically analyze the capacities and load-displacement behavior of reinforced concrete structural elements by strengthening such strips.Article Citation - WoS: 23Citation - Scopus: 23Effect of Anchorage Number and Cfrp Strips Length on Behavior of Strengthened Glulam Timber Beam for Flexural Loading(Sage Publications inc, 2021) Isleyen, Ummu Karagoz; Ghoroubi, Rahim; Mercimek, Omer; Anil, Ozgur; Togay, Abdullah; Erdem, R. TugrulLaminated wooden beams are more preferred in the production of wooden structures than solid timber beams because they have a higher load-carrying capacity and allow larger openings to be used in the structure. The widespread use of wooden structures and the increasing size of the structures have revealed the need for strengthened laminated wooden beams and increase their ultimate load capacity. It has become necessary to develop reinforcement details to increase the ultimate load capacity of laminated wooden beams in wooden railroads or highway bridge beams, where the traffic load increases, especially in large wooden structures, in cases where large openings must be passed. Within the horizon of the study, the behavior and performance of three-layer glulam wooden beams strengthened with anchorage and non-anchorage CFRP strips with different bonding length under flexural loading were investigated experimentally. The three-point bending test was applied to glulam timber beam test specimens produced by laminating yellow pine wood material using the polyurethane adhesive. General load-displacement behaviors, ultimate load capacity, initial stiffness, displacement ductility ratios, and energy dissipation capacities were obtained. The increase in the bonding length of the CFRP strips used for strengthening in the glulam timber beam specimens and the use of CFRP fan type anchors at the strip ends increased the ultimate load capacity and initial stiffness values of the wooden beams, as well as the displacement ductility ratios and energy dissipation capacity values.Article Citation - WoS: 4Citation - Scopus: 4Behaviour of Steel Beams Retrofitted With Anchored Carbon-Fibre Polymer Strips(Ice Publishing, 2022) Mercimek, Omer; Ghoroubi, Rahim; Baran, Mehmet; Anil, OzgurSteel bridge beams can be damaged due to increased traffic loads and environmental impacts. An experimental study on the use of bonded and mechanically anchored carbon-fibre-reinforced polymer (CFRP) strips was undertaken to assess the retrofitting of such steel beams. The number of mechanical anchors used in the ends of the bonded strips was varied from zero to eight. The steel beam samples were tested under four-point loading. Loading was applied as an increasingly high static load and a low repetitive fatigue load. The load-displacement behaviour under the effects of static and fatigue loading and the strain distributions along the strips were measured and interpreted. The results showed that retrofitting cracked steel beams with CFRP strips is an effective method. In addition, retrofitting with anchored strips increased the performance of cracked beams under the effects of both static and fatigue loading.Article Citation - WoS: 24Citation - Scopus: 28Behavior of Glulam Timber Beam Strengthened With Carbon Fiber Reinforced Polymer Strip for Flexural Loading(Sage Publications Ltd, 2021) Isleyen, ummu K.; Ghoroubi, Rahim; Mercimek, Omer; Anil, Ozgur; Erdem, Recep TugrulIn the last 20 years, the use of wooden structures and their dimensions have gradually increased. The wood application has increased in different structures such as multistory buildings, sports, industrial facilities, road and railway bridges, power transmission lines, and towers. The widespread use and size of wood structures have increased the research on developing special types of wood products supported by composite materials. Laminated wood elements are the leading composite wood materials. Laminated wooden beams allow making much larger openings than standard solid wood structural elements. The development of the sizes and usage areas of wooden structures has increased the capacity of glulam structural elements and reveals the need to improve their performance. Carbon fiber reinforced polymers (CFRPs) are the most suitable options for increasing the bearing capacity values of glulam beams and improving general load-displacement behaviors. In this study, the use of CFRP strips in different layouts to increase glulam wooden beams and the application of CFRP fan-type anchors in the CFRP strip endpoints are the studied variables. Anchored and non-anchored glulam wooden beams reinforced with CFRP strips with different layouts were tested using a three-point bending test. The ultimate load capacity, initial stiffness, displacement ductility ratio, energy dissipation capacity, failure mechanisms, and general load-displacement behavior of wooden beam test specimens were obtained and interpreted as a result of the experiments.Article Citation - WoS: 3Citation - Scopus: 3Numerical and Experimental Modelling of Flow at Tyrolean Weirs(Elsevier Sci Ltd, 2021) Yildiz, Ali; Marti, Ali Ihsan; Gogus, MustafaIn this study, a small-scaled Tyrolean weir model was constructed in the laboratory environment and a series of experiments were conducted on it, for two different rack inclinations (theta(1) = 18 degrees and theta(2) = 25 degrees) and three different bar spacings (e(1) = 3 mm, e(2) = 6 mm and e(3) = 10 mm) for a range of upstream flow discharges. The flow rates passing through the racks and going downstream over the racks were measured. Empirical equations for the discharge coefficient and water capture capacity of the Tyrolean weirs were determined by applying dimensional analysis to the parameters involved in the phenomenon. The related dimensionless parameters were presented with graphs and empirical equations for discharge coefficients were derived, coefficient of determination R-2 of equations for theta(1) = 18 degrees and theta(2) = 25 degrees are found 0.838 and 0.825 respectively. According to results obtained from experimental data, C-d increases as the Froude number ((F-r)(e)) between bars increases and water capture capacity [(q(w))(i)/(q(w))(T)] of the racks decreases with increasing ((F-r)(e)). Also, a numerical model of the Tyrolean weir was generated by using Flow-3D software and it was shown that the results of the numerical analysis were very consistent with the physical model results at large bar spacing such as e = 10 mm. As the bar spacing (e) reduces, the success of the numerical model giving consistent results with physical model is decreasing.
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