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Öğe AN EXPERIMENTAL EVALUATION OF WORKABILITY AND BLEEDING BEHAVIORS OF ULTRA-SONICATED NANO ZINC OXIDE (n-ZnO) DOPED CEMENT PASTES INCORPORATED WITH FLY ASH(Begell House Inc, 2024) Celik, Fatih; Colak, Andac Batur; Yildiz, Oguzhan; Bozkir, Samet MufitIn this study, the workability and bleeding behaviors of ultra-sonicated nano zinc oxide (n-ZnO) doped cement pastes incorporated with fly ash have been experimentally investigated. Therefore, the effects of nano zinc oxide (n-ZnO) additions at different amounts by mass (0.0, 0.3, 0.6, 0.9, 1.2, and 1.5%) on the bleeding and the workability properties (mars cone flow time, mini slump spread diameter, and plate cohesion) of cement -based grouts incorporated with fly ash (FA) as mineral additive at different constitutes (0% -for control purpose, 5, 10, 15, 20, 25, and 30%) were investigated. The use of FA as a mineral additive in grout samples resulted in improvements in the workability behavior of the grout samples as expected. Increase amount of n-ZnO in the grout mixtures has made mini slump flow diameter of the samples noticeably decrease. Although certain changes seem to have been observed, it has been understood that the increase in the amount of n-ZnO in the injection matrix generally does not change the Marsh cone flow time of mineral -added cement -based grouts. Remarkable increases in plate cohesion values were measured because of the increase in the content of nano zinc oxide for all mixtures. At the same time, just like the FA effect, bleeding values tend to decrease due to the increase in the amount of nano zinc oxide in grout mixes. Moreover, the results obtained showed that the artificial neural network model can make predictions with very high accuracy.Öğe An Experimental Investigation on Workability and Bleeding Behaviors of Cement Pastes Doped with Nano Titanium Oxide (n-TiO2) Nanoparticles and Fly Ash(Tech Science Press, 2023) Celik, Fatih; Yildiz, Oguzhan; Colak, Andac Batur; Bozkir, Samet MufitIn this study, the workability of cement-based grouts containing n-TiO2 nanoparticles and fly ash has been investigated experimentally. Several characteristic quantities (including, but not limited to, the marsh cone flow time, the mini slump spreading diameter and the plate cohesion meter value) have been measured for different percentages of these additives. The use of fly ash as a mineral additive has been found to result in improvements in terms of workability behavior as expected. Moreover, if nano titanium oxide is also used, an improvement can be obtained regarding the bleeding values for the cement-based grout mixes. Using such experimental data, a multi-layer perceptron artificial neural network model has been developed (5 neurons in the hidden layer of the network model have been developed using a total of 42 experimental data). 70% of the data employed in this model have been used for training, 15% for validation and 15% for the test phase. The results demonstrate that the artificial neural network model can predict Marsh cone flow time, mini slump spreading diameter and plate cohesion meter values with an average error of 0.15%.Öğe An Experimental Investigation on Workability and Bleeding Features(Amer Concrete Inst, 2022) Celik, Fatih; Colak, Andac Batur; Yildiz, Oguzhan; Bozkir, Samet MufitIn this experimental study, the workability and bleeding properties of cement-based grout mixtures combined with fly ash (FA) and colloidal nanopowder (n-Al2O3) were investigated, and some prediction models were developed with an artificial neural network (ANN). Marsh cone flow time, mini-slump spreading diameter, and Lombardi plate cohesion of the grout samples were measured based on the workability test. Test results showed that the use of FA as mineral additive in the grout samples positively contributed to an increase of the fluidity of the grout samples as expected. Considerable effects were observed on workability features of grout mixtures with the addition of nano alumina because of having a large specific surface area. In addition, the use of nano alumina together with FA in grout mixtures contributes to the stability of these mixtures by looking at changes in bleeding values. Using the experimental data obtained, an ANN model was developed to predict the values of Marsh cone flow time, mini-slump spreading diameter, and plate cohesion. The developed ANN model can predict mini-slump spreading diameter with an error rate of -0.04%, Marsh cone flow time value with an error rate of -0.23%, and plate cohesion value with an error rate of -1.07%.Öğe Analysing of nano-silica usage with fly ash for grouts with artificial neural network models(Emerald Group Publishing Ltd, 2023) Celik, Fatih; Yildiz, Oguzhan; Colak, Andac Batur; Bozkir, Samet MufitWhen grout is used to penetrate voids and cracks in soils and rock layers, easy and effective pumping of the grouts is vital, especially for grouting works during geotechnical improvements. For this reason, improving the rheological parameters of cement-based grouts and increasing their fluidity are important for effective grouting injection. In this study, an experimental investigation and analysis using artificial neural network (ANN) models were used to discover how nano silica (n-SiO2) together with fly ash affects the rheological behaviour of cement-based grouts. The effects of nano silica (n-SiO2) additions at different contents by mass (0.0%, 0.3%, 0.6%, 0.9%, 1.2% and 1.5%) on the plastic viscosity and yield stress values of cement-based grouts incorporating fly ash as a mineral additive at different amounts (0% - as a control, 5%, 10%, 15%, 20%, 25% and 30%) were investigated. Using the experimental data obtained, a feed-forward (FF) back-propagation (BP) multi-layer perceptron (MLP) artificial neural network (ANN) was developed to predict the plastic viscosity and yield stress of cement-based grouts with nano silica nanoparticle additives. The ANN model developed can predict the plastic viscosity and yield stress values of cement-based grouts containing nano silica nanoparticle-doped fly ash with high accuracy.Öğe Characterization of shear strength and interface friction of organic soil(Trans Tech Publications Ltd, 2020) Hamed, Majid; Sidik, Waleed S.; Canakci, Hanifi; Celik, Fatih; Georgees, Romel N.This study was carried out to undrestand some specific problems that limit safe design and construction of structures on problematic soils. An experimental study was undertaken to examine the influence of the rate of loading and moisture content on shear strength of organic soil. Influece of moisture content on interface friction between organic soil and structural material was also attempted. A commonly used soil in Iraq was prepared at varying moisture contents of 39, 57 and 75 %. The experimental results showed that the increase in water content will decrease the shear stress and the internal friction angle. An increase of the shear rate was found to decrease the shear stress and internal friction angle at all percetanges of water contents. Further, direct shear tests were carried out to detect the interface shear stress behavior between the organic soil and structural material. The results revealed that the increase in water content was shown to have significant negetavie effects on the interface internal friction and angle shear strength. © 2020 Trans Tech Publications Ltd, Switzerland.Öğe COMPARISON OF NUMERICAL ANALYSIS OF A SINGLE-SPAN STEEL PROTOTYPE STRUCTURE AND A SCALE MODEL STRUCTURE UNDER THE EFFECT OF SEISMIC LOADS(Konya Teknik Univ, 2023) Kebeli, Yunus Emre; Teberik, Seyma; Aydin, Ersin; Celik, FatihOne of the biggest problems encountered in many experimental studies is examining a real- size structure in the field or in a laboratory environment. With today's technological opportunities, it is possible to experimentally examine a real-sized structure in the field or in a laboratory environment. However, to do this, the manufacture of a large, real-size structure, experimental setup and measuring devices are required, which are costly. For this reason, it is not always possible to reach such a laboratory environment. It is very difficult to experimentally examine large-scale structures both economically and in terms of time saving. In this context, in this study, a scaling factor (A) widely accepted in the literature was used to design a scaled model to represent a real- size structure. A=10 was used in this scaling approach. A real-size three-story single-span steel prototype building was scaled to a laboratory-scale model structure and analyzed digitally with the Sap2000 program. The natural period/frequency values of the real-size prototype structure and the scaled model modeled in the Sap2000 program were examined. Later, Time history analyzes were performed using real earthquake records from El Centro (1940), Kobe (1995) and Northridge (1994). While real earthquake records were used as they were in the analysis of the prototype structure, these real earthquake records were used by scaling them depending on the scaling factor A in the analysis of the scaled model. Subsequently, the digital analyzes of the prototype and scaled structure were compared by looking at the acceleration and displacement values of each floor. It was observed that the results were close to each other when scaled according to the scaling factor (A). This situation demonstrated the accuracy of the scaling rates applied within the scope of the study. Thus, it has been shown that a real-size structure can be scaled to a model in a laboratory environment with correct scaling methods and that this prototype structure can be analyzed with more economical and simple methods.Öğe Developing Prediction Model on Workability Parameters of Ultrasonicated Nano Silica (n- SiO2) and Fly Ash Added Cement-Based Grouts by Using Artificial Neural Networks(Amer Soc Testing Materials, 2022) Colak, Andac Batur; Yildiz, Oguzhan; Celik, Fatih; Bozkir, Samet MufitIn this experimental study, the workability and bleeding properties of cement-based grout mixes combined with fly ash (FA) and nano silica (n-SiO2) as colloidal nanopowder were investigated, and some prediction models were developed with the artificial neural network. The Marsh cone flow time, mini slump spreading diameter, and plate cohesion meter values of samples prepared in different concentrations have been measured and analyzed experimentally to investigate the workability properties. Moreover, bleeding tests were carried out on the grout mixtures prepared within the scope of this experimental study. Test results showed that the usage of FA as a mineral additive in the grout samples positively contributed to an increase on the fluidity of the grout samples as expected. Although the increase in n-SiO2 content in the grout mixes resulted in an increase in the Marsh cone flow time of the grout mixes, it resulted in a decrease in the mini slump spreading diameter of the samples. The increase in the plate cohesion values of the grout mixtures was also observed in the n-SiO2 added grout mixtures. At the same time, the bleeding values of the grout mixes with and without mineral additives of 0.9 % or more with n-SiO2 additives remained above 900 ml (below 10 % bleeding rate). The artificial neural network model can predict the workability properties of cement-based grouts containing n-SiO2 nanoparticle-doped FA with high accuracy.Öğe Examination of the mechanical properties and failure pattern of soilcrete mixtures modified with rice husk ash(Taylor & Francis Ltd, 2020) Celik, Fatih; Canakci, HanifiThis paper evaluates the unconfined compressive strength (UCS), stability (bleeding), modulus of elasticity and failure patterns of cement-based grout mixtures that were prepared by placing of rice husk ash (RHA) with cement at various water to binder (w/b) ratios. In order to investigate these parameters, UCS and bleeding tests were conducted on the soilcrete samples that prepared at 5, 10, 20 and 30% replacement level of RHA with cement for .75, 1.00 and 1.25 w/b ratios. Test results showed that the UCS values of the samples for 28 day curing are higher than 1 MPa andE/q(u)ratios obtained from soilcrete mixtures were less than the corresponding value from slurry clay-cement mixes given in the literature. In addition, all bleeding test results are lower than the level of .5%. Finally, most of the mixtures prepared for this study failed along foliations.Öğe Hip-related functional limitations in individuals with idiopathic scoliosis: a controlled trial(Springer, 2024) Celik, Fatih; Gokalp, Burcu Senol; Demirkiran, Goekhan; Bek, Nilgun; Yakut, Yavuz; Yagci, GozdeBackground Since scoliosis is a three-dimensional deformity, it causes some movement limitations in the spine and related joints. However, functional limitations associated with scoliosis-related hip joint involvement are the subject of research. Aims This study aims to investigate the physical characteristics and functional limitations associated with idiopathic scoliosis (IS), focusing on hip joint. Methods Demographic characteristics, scoliosis-specific assessments and hip joint active range of motion (RoM), lumbar mobility (Modified Schober test), lumbopelvic stability (Single leg squat test-SLS), hip joint position sense, lower extremity balance (Y-balance test) and lower extremity functionality (Lower extremity functional scale-LEFS) were evaluated. Results The study included 120 individuals, with 86 in the scoliosis group (mean age: 15.7 +/- 3.4 years) and 34 in the control group (mean age: 16.1 +/- 4.8 years). The scoliosis group exhibited limited RoM of the hip joint in flexion, extension, right abduction, adduction, internal rotation, and left external rotation compared to controls (p < 0.001). Lumbar mobility was decreased (p < 0.001). In the joint position sense test, the mean difference for right flexion was and for left flexion. Bilateral decreased SLS test performances (p < 0.001) and Y-balance test performance (p < 0.05) in individuals with IS. LEFS scores were statistically different but not clinically different between groups (p < 0.05). Conclusion Individuals with IS show decreased hip mobility, lumbopelvic stability, hip joint position sense, and balance compared to healthy peers; however, these limitations do not have a clinical impact on daily living activities.Öğe Mapping investigation based on engineering geology of a developing urban area (Niğde, Turkey)(Springer Science and Business Media Deutschland GmbH, 2021) Celik, Fatih; Öztürk, Muhammed Zeynel; Şener, Mehmet Furkan; Arıöz, Ömer; Erbil, MerveDefinitions of urban geological environments are usually required to provide information about an engineering basis for planners and design engineers to prepare a rational land use planning and developing urban areas. Therefore, the geological mapping investigation method can be a beneficial way of defining urban geological environments visually. In this study, the Engineering Geological Mapping Method (EGMM) was used to investigate and present the geotechnical and geological data obtained from Niğde city of Turkey. Around forty-five unpublished reports that were obtained from the construction work done around the study area were evaluated as detail. Then, the study area was divided into five different regions which were considered their geological characteristics. In each region, nine unpublished reports were selected and analyzed for interpreting the data and plotting the geotechnical and geological maps. The main indispensable parameters for geotechnical design engineers were drawn by using the data obtained from the different boreholes for Niğde city. These drawn maps by GIS technic: (1) groundwater table, (2) liquefaction zone, (3) plasticity index, (4) bearing capacity, (5) soil classification, and (6) SPT results. For preparing the maps, two types of interpolation methods were used (minimum curvature and Voronoi polygons methods). The Geographic Information System (GIS) was used to rearrange and control all this information and to prepare engineering geotechnical and geological maps. As a result, the Engineering Geological Mapping Method applied for this study is to show more crucial for preventing mistakes making in practical works during preparing urban extension planning for developing cities in the future. © 2021, Saudi Society for Geosciences.Öğe Observation of nano powders and fly ash usage effects on the fluidity features of grouts(Techno-Press, 2022) Celik, Fatih; Yildiza, Oguzhan; Bozkir, Samet M.The pumpability of the grouts is significant issue in concept of the rheological and workability properties during penetrating to voids and cracks. To improve the fluidity features of the grout mixes, the usage of Colloidal Nano Particular Powders (CNPPs) with mineral additives such as fly ash (FA) can contribute. Therefore, the main purpose of this study can be explained as investigating the usage effects of four types of Colloidal Nano Particular Powders (n-TiO2, n-ZnO, n-Al2O3 and n-SiO2) as nano additives on the rheological, workability and bleeding properties of cement-based grout incorporated with fly as. Test results showed that the usage of FA in the grout samples positively contribute to increase on the fluidity of the grout samples as expected. The dilatant behavior was observed from the results for all mixes. Observing the effect of nano -sized additives in such cement-based grout mixtures with high fluidity has presented remarkable effects in this study.Öğe Rheological and workability effects of bottom ash usage as a mineral additive on the cement based permeation grouting method(Elsevier Sci Ltd, 2020) Celik, Fatih; Akcuru, OsmanThis study presents the effects of rheological and fluidity features of cement based grouts incorporated with bottom ash (BA) as mineral additive on permeation grouting method. In this context, some experimental and analytical analyses were conducted and their results were presented. In terms of rheological and workability tests, the test program included 28 different mixtures having 0% (for control purposes), 5%, 10%, 15%, 20%, 25% and 30% bottom ash content and four water to binder ratios (w/b = 0.75,1.00, 1.25 and 1.50). Plastic viscosity, apparent viscosity, and the yield stress of the mixtures based on rheological properties were measured for all mixtures. At the same time, marsh cone flow time, plate cohesion, and mini slump diameter in terms of workability features were obtained. In second part of this study, all rheological properties obtained from the mixtures were used for evaluating permeation grout method based on two analytical flow models (radial and spherical flow models). All test results showed that rheological parameters (especially plastic viscosity) and workability properties of the cement based grouts incorporated with BA are very important for determining of the permeation grouting design parameters such as injection pressure. (C) 2020 Elsevier Ltd. All rights reserved.
