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Evaluation of pH Value by Using Image Processing
(Polish Acad Sciences Inst Physics, 2017) Beycioğlu, Ahmet; Çomak, Bekir; Akçaabat, Dilara
In this study strong HCl acid was titrated with a strong base of NaOH. Increasing pH values were observed during such titration. Depending on the existence of indicator in the solution, the equivalence point was determined when the color of the solution had turned into pink. After finding the equivalence point, images were taken after every addition of base to the acid solution. These images were evaluated using red, green and blue values of the pixels, through an image processing program. After analyzing the image results, it was found that the percentage of red values had increased with the increasing pH value. As a result, the image processing techniques can be used as an alternative approach to find pH values of titrated solutions.
Enhanced Predictive Models for Construction Costs: A Case Study of Turkish Mass Housing Sector
(Springer, 2019) Uğur, Latif Onur; Kanıt, Recep; Erdal, Hamit; Namlı, Ersin; Erdal, Halil İbrahim; Baykan, Umut Naci; Erdal, Mürsel
The analysis of a construction project, regarding cost, is one of the most vital problem in planning. Due to its nature, the construction sector is an area of strong competition and estimation works are of vital importance. In recent years the Turkish Republic has started a serious urban regeneration movement in parallel to its economic development. This study is based on the drawings and quantities of 63 detached multi-story reinforced concrete housing unit projects of the Housing Development Administration (TOKI) and the Turkey Residential Building Cooperative Union (TURKKONUT). TOKI is a public company and its projects are that have been applied to 282 separate projects and are being applied to a further 266. On the other side TURKKONUT is a union of 1347 private building cooperative and have been completed 200,000 residential building. The main objective of this study is to improve the estimation accuracy of individual machine learning techniques, namely multi-layer perceptron and classification and regression trees and compares the performance of two machine learning meta-algorithms (i.e., bagging and random subspace) on a real world construction cost estimation problem. The study shows that the estimation accuracy of ensemble models are better than the models that constructed by their base learners and ensemble models may improve individual machine learning models.
Enzyme treated CNF biofilms: Characterization
(Elsevier, 2018) Poyraz, Bayram
The objective of this study was to characterize on the chemical, mechanical, electrical and thermal properties of nanofibrillated cellulose based polyvinyl alcohol (PCNF) and silica (SiCNF) films obtained from Pulpzyme HC 2500 and Celluclast 1.5 L enzyme treated kraft-NaBH4 pulps. Morphological alterations were monitored with SEM. Thermal stability, chemical characterization and crystallization were determined using TGA and FT-IR. Young's and storage moduli of the films were determined via a universal testing machine and DTMA. Dielectric properties were evaluated using an impedance analyzer. In the PCNF films, new vibrations and chemical shifts were observed. The crystallinity values of the SiCNF films calculated from the FT-IR were in agreement with the TGA results, revealing that the lowest crystallinity value was in the SiCNF. The higher Young modulus and elongation at break value were obtained in the neat the CNF films while the lowest values were observed in the neat SiCNF films. However, the SiCNF films revealed higher thermo-mechanical property. The PCNF and SiCNF films exhibit more visible dielectric behavior than that of the neat CNF films. Higher thermal stability, thermo-mechanical and mechanical properties were determined in the Pulpzyme HC 2500 enzyme treated films. Hence, this study evidenced that the properties of CNF films having different matrix are influenced by both the enzymes employed. (C) 2018 Elsevier B.V. All rights reserved.
Environmental performance analysis of insulated composite facade panels using life cycle assessment (LCA)
(Elsevier Sci Ltd, 2019) Yılmaz, Emrah; Arslan, Hakan; Bideci, Alper
The construction sector, which accounts for 10% of global economic activity, consumes approximately 40% of the world's energy and materials. Besides, it accounts for the consumption of 17% of world water resources and 25% of manufactured wood and is responsible for about 50% of greenhouse gas emissions. This situation makes the assessment of the environmental impact of construction materials fundamental. The Life Cycle Assessment (LCA) methodology is a scientific method that is used to identify, report and manage the environmental impacts of a product, starting with the acquisition of raw materials, including production, shipment, consumer use, and disposal as waste after use. In this study, environmental effects of 50 mm thick polyurethane and rockwool filled composite facade panels were determined by using LCA method and compared. Hence, the facade panels' cradle-to-gate process (raw material supply, production and disposal phases) were examined. As a result of the study, it is seen that the polyurethane filled composite facade panel has more advantageous environmental performance than the rockwool filled composite facade panel. (C) 2019 Elsevier Ltd. All rights reserved.
Fuzzy logic approach for estimating bond behavior of lightweight concrete
(Techno-Press, 2014) Arslan, Mehmet Emin; Durmuş, Ahmet
In this paper, a rule based Mamdani type fuzzy logic model for prediction of slippage at maximum tensile strength and slippage at rupture of structural lightweight concretes were discussed. In the model steel rebar diameters and development lengths were used as inputs. The FL model and experimental results, the coefficient of determination R2, the Root Mean Square Error were used as evaluation criteria for comparison. It was concluded that FL was practical method for predicting slippage at maximum tensile strength and slippage at rupture of structural lightweight concretes.
FUZZY LOGIC MODEL FOR PREDICTION OF COMPRESSIVE STRENGTH OF CONCRETE BY USE OF NON-DESTRUCTIVE TEST RESULTS
(Serban Solacolu Foundation, 2017) Baykan, Umut Naci; Erdal, Mürsel; Uğur, Latif Onur
In this study, a fuzzy logic prediction model for compressive strength of concrete was developed based on various nondestructive tests, such as Windsor Probe Penetration Test, Ultrasonic Pulse Velocity and Schmidt Hammer. Experimental results of non-destructive tests were used to construct the fuzzy logic model. The obtained results with fuzzy logic were compared with the multiple linear regression model and experimental values. It was observed that, non-destructive tests' determination abilities were increased by using fuzzy logic. Results have shown that, fuzzy logic systems have strong potential for predicting 28 days compressive strength using Windsor Probe Penetration value, Ultrasonic Pulse Velocity and Schmidt Hammer rebound as inputs variables.
Effects of use of alkaline mixing waters on engineering properties of cement mortars
(Taylor & Francis Ltd, 2018) Çomak, Bekir
In this study, the effect of pH level of mixing water on physical, mechanical and microstructure properties of cementitious mixtures was examined. In order to adjust the pH level of mixing water, various ratios of NaOH were added to ultra-pure water. Therefore, in total, six different mixing waters were obtained including the reference mixing water, pH10, pH11, pH12, pH13 and pH14. Mortar samples were produced using the obtained mixing waters with CEM I 42.5R Portland cement, then physical and mechanical properties of the cement mortars were determined on the 7th, 14th, 28th and 90th days. In addition, microstructure properties of the cement mortar specimens were determined after the 28days curing period. Porosity measurements by mercury intrusion porosimetry were also examined after the 28days cure periods. At the end of study, it was determined that the alkaline mixing waters (up to pH13) have positive effects on the compressive strength and workability of the cement mortars. The best result was obtained with pH12 mixing waters.
Effects of hemp fibers on characteristics of cement based mortar
(Elsevier Sci Ltd, 2018) Çomak, Bekir; Bideci, Alper; Bideci, Özlem Sallı
In recent years, using addition of fibers with plant origin in concretes has increased significantly. They not only enhance the mechanical characteristics of cement mortars, but also they are renewable, easy to access and cheap and this makes the use of plant fibers more widespread. Hemp fiber is a plant, which is planted in many places of the world and obtained in large amounts, is environmentally friendly and also used in manufacturing of composite materials. In this study, hemp fiber reinforced cement mortars with different ratios (0%, 1%, 2%, 3%) and different lengths (6 mm, 12 mm and 18 mm) were manufactured. Density, water absorption, compressive strength, flexural strength, compressive strength after flexural tensile and splitting tensile strength tests were performed on manufactured samples. Also, in order to determine the inner structural characteristics of samples, SEM analysis was conducted. As a result of the study, it was determined that cement mortars reinforced with 2-3% amount and 12 mm length of natural hemp fiber give the optimum results. (C) 2018 Elsevier Ltd. All rights reserved.
Effects of basalt and glass chopped fibers addition on fracture energy and mechanical properties of ordinary concrete: CMOD measurement
(Elsevier Sci Ltd, 2016) Arslan, Mehmet Emin
This study investigates fracture behavior of basalt fiber reinforced concrete (BFRC) and glass fiber reinforced concrete (GFRC) comparatively. For this purpose, three-point bending tests were carried out on notched beams produced using BFRC and GFRC with 0.5, 1, 2 and 3 kg/m(3) fiber contents to determine the value of fracture energy. Fracture energies of the notched beam specimens were calculated by analyzing load versus crack mouth opining displacement (CMOD) curves by the help of RILEM proposal. In addition, microstructural analysis of the three components; cement paste, aggregate, basalt and glass fiber were performed based on the Scanning Electron Microscopy and Energy-Dispersive X-ray Spectroscopy examinations and analysis were discussed. The results showed that the effects of the fiber contents on fracture energy were very significant. The splitting tensile and flexural strength of BFRC and GFRC were improved with increasing fiber content whereas a slight drop in flexural strength was observed for high volume of fiber content. On the other hand, effect of fiber addition on the compressive strength and modulus of elasticity of the mixtures was insignificant. (C) 2016 Elsevier Ltd. All rights reserved.
Effect of Elevated Temperatures on Properties of Blended Cements with Clinoptilolite
(Kaunas Univ Tech, 2016) Beycioğlu, Ahmet; Aruntaş, Hüseyin Yılmaz; Gencel, Osman; Lobland, Haley E. Hagg; Şamandar, Ayhan; Brostow, Witold
We have investigated the effect of elevated temperature on properties of clinoptilolite blended cements. Clinoptilolite was used at 5 %, 10 %, 15 % and 20 % replacement by weight for Portland cement while sand and water quantities were kept constant in all mix designs. Dry weights, flexural strengths, and compressive strengths of specimens were determined as a function of time. The same properties were again evaluated after specimens, having reached the age of 90 days, were exposed to 300 degrees C, 400 degrees C and 500 degrees C temperatures for 3 h. Initial setting times for all cements prepared were >= 60 minutes, the limiting time according to TS EN 197-1. The mortars with 5 % or 10 % cliniptilolite substitution have compressive strength exceeding 42.5 MPa after being subjected to 400 degrees C and 500 degrees C.
Effect of fly ash on rebars bond strength in the expanded clay aggregate lightweight concrete
(Stowarzyszenie Producentow Cementu, 2012) Subaşı, Serkan; Emiroğlu, Mehmet
The addition of fly ash, replacing cement in light weight concrete from expanded clay aggregate on rebars bond strength was studied. It was found that the bond strength is increasing with the rise of compressive strength of concrete i.e. with the content of cement in concrete. The fly ash addition of 10% caused the increase both of compressive and bond strength. However, the addition of 20% has an disadvantageous effect. The compressive strength of concrete as well as the rebars bond strength were decreasing.
Effect of basalt fibers on fracture energy and mechanical properties of HSC
(Techno-Press, 2016) Arslan, Mehmet Emin
Fracture energy is one of the key parameters reveal cracking resistance and fracture toughness of concrete. The main purpose of this study is to determine fracture behavior, mechanical properties and microstructural analysis of high strength basalt fiber reinforced concrete (HSFRC). For this purpose, three-point bending tests were performed on notched beams produced using HSFRCs with 12 mm and 24mm fiber length and 1, 2 and 3 kg/m(3) fiber content in order to determine the value of fracture energy. Fracture energies of the notched beam specimens were calculated by analyzing load versus crack mouth opining displacement curves by the help of RILEM proposal. The results show that the effects of basalt fiber content and fiber length on fracture energy are very significant. The splitting tensile and flexural strength of HSFRC increased with increasing fiber content whereas a slight drop in flexural strength was observed for the mixture with 24mm fiber length and 3 kg/m(3) fiber content. On the other hand, there was no significant effect of fiber addition on the compressive strength and modulus of elasticity of the mixtures. In addition, microstructural analysis of the three components; cement paste, aggregate and basalt fiber were performed based on the Scanning Electron Microscopy and Energy-Dispersive X-ray Spectroscopy examinations.
Cyclic behavior of GFRP strengthened infilled RC frames with low and normal strength concrete
(Walter De Gruyter Gmbh, 2019) Arslan, Mehmet Emin; Durmuş, Ahmet; Hüsem, Metin
This paper presents the experimental behavior of plane, non-strengthened and glass fiber reinforced polymer (GFRP) strengthened infilled reinforced concrete (RC) frames with low strength concrete (LSC) and normal strength concrete (NSC) under lateral reversed cyclic loading. For this purpose, eight full-scale, one-bay, one-storey plane and infilled (brick and aerated concrete blocks which are commonly used in RC construction) RC frames with LSC and NSC were produced and in-plane lateral loading tests were carried out. Test results indicate that infill walls considerably change the behavior of frames by increasing rigidity and load carrying capacity. By contrast, GFRP fabric used for strengthening of infilled RC frames improves ductility, load carrying and energy dissipation capacity of in filled frames with ISC and NSC as well. After all the test results were evaluated together, a GFRP strengthened brick infilled frame demonstrated the best performance under cyclic lateral loading.
Cyclic behaviors of different type of hollow brick infill walls: A hinged rigid frame approach
(Elsevier Sci Ltd, 2019) Pul, Selim; Arslan, Mehmet Emin
The main purpose of this study is to examine the behavior of the brick masonry and infill walls under cyclic horizontal loads, irrespective of reinforced concrete frames. For this purpose, the test walls, which are produced as non-plastered (plane), two side plastered and two side plastered and strengthened with zinc coated steel wire mesh by using vertical and horizontal hollow brick walls were tested in a rigid hinged steel loading frame under lateral cyclic loading. The findings were evaluated in terms of load carrying capacity, ductility and energy dissipation capacities. The tests carried out showed that the expected increases were provided any type of plastered walls in terms of stiffness with respect to the reference non-plastered walls. Besides this, wired mesh used in plastered walls increased significantly the ductility and consequently the energy dissipation capacity of the walls by maintaining wall integrity in an advanced stage of the loading. Also, both hollow brick and vertical brick infill walls strengthening with wired mesh increase load carrying capacity of the wall test specimens. Load carrying and energy dissipation capacities of wire meshed specimens almost five times more than those of plane test walls. (C) 2019 Elsevier Ltd. All rights reserved.
Workability and mechanical properties of self-compacting concretes containing LLFA, GBFS and MC
(Elsevier Sci Ltd, 2014) Beycioğlu, Ahmet; Aruntaş, Hüseyin Yılmaz
This paper presents the results of an experimental investigation carried out to study the effect of Low Lime Fly Ash (LLFA), Granulated Blast Furnace Slag (GBFS) and Micronized Calcite (MC) on both workability and mechanical properties of Self Compacting Concretes (SCCs). In the experimental program, Portland cement was partially replaced with LLFA and GBFS as 20%, 40% and 60% by weight of total binder and also MC was partially replaced with total aggregates as 5% and 10% for all mixtures containing LLFA and GBFS. At the fresh state, the workability of SCCs was evaluated by slump flow diameter and time, V-funnel flow time, L-box height ratio, U-Box height difference and.1-Ring flow diameter tests. Furthermore, compressive strength, splitting tensile strength, ultrasonic pulse velocity, elasticity modulus of SCCs were measured at hardened state at 7, 28 and 90 days. Results showed that using MC, LLFA and GBFS positively affected the flowability, passing ability and viscosity of SCCs. When LLFA and GBFS substituted as high volume, in comparison with normal concrete, the SCCs showing adequate mechanical performance had been able to be produced. (C) 2014 Elsevier Ltd. All rights reserved.
Utility of polyparaphenylene terephtalamide fiber in hot mix asphalt as a fiber
(Elsevier Sci Ltd, 2016) Morova, Nihat; Serin, Sercan; Terzi, Serdal; Saltan, Mehmet; Küçükçapraz, D. Özdemir; Karahançer, Şebnem Sargın; Erişkin, Ekinhan
In this study, utility of polyparaphenylene terephtalamide (PT) was investigated in hot mix asphalt as a fiber. For this aim samples were prepared with limestone aggregate at different proportions. Marshall Stability test was applied and optimum bitumen content was determined. In the second stage of the study, new samples were prepared using different polyparaphenylene terephtalamide fiber (PTF) rates of 0.25%, 0.50%, 0.75%, 1.00%, 1.50%, 2.00% based on optimum bitumen content. When examining test results, samples which prepared using 0.25% PTF rate gave highest Marshall Stability result. At the final stage of the study, different bitumen contents (4.15%, 4.65% and 5.15%) were conducted for the best fiber rate (0.25%) and close to this result (0.50% and 0.75%). Thus, the effect of bitumen content on determined fiber rate at the second stage of the study was investigated. Also Indirect Tensile (IDT) Strength Test was performed on hot mix asphalt (HMA) samples preparing at 0.25%, 0.50% and 0.75% fiber rates and moisture sensitivities were determined. All results showed that, the best fiber rate was 0.25% and determined optimum bitumen content remain constant with the fiber additive for the reference samples. Besides, some sample groups which prepared using different PTF rates proved the specification limits and it was said that; PTF can be used in asphalt concrete as a fiber additive. (c) 2015 Elsevier Ltd. All rights reserved.
Utilizing of waste ceramic powders as filler material in self-consolidating concrete
(Elsevier Sci Ltd, 2017) Subaşı, Serkan; Öztürk, Hakan; Emiroğlu, Mehmet
Using filler materials finer than 0.125 mm is quite effective on the fresh state properties, strength and durability of self-consolidating concretes. Most common filler materials used in self -consolidating concretes are minerals, blended cements and natural or artificial pozzolans. In this study, usability of granulated waste ceramic powder as filler material in self -consolidating concretes was investigated. Properties of self -consolidating concretes produced with 5501 kg/m(3) dosage and cement was replaced with (WCP) in the amounts of 5%, 10%, 15% and 20% (by weight) were determined in the fresh and hardened phases. As a result, it is determined that use of WCP has some positive effect on viscosity of the mixes. However, a slight decrease was observed on the strength values based on the substitution of cement with ceramic powder. It can be concluded that finely ground WCP5 could be evaluated up to 15% for production of self-consolidating concretes as a filler material if the strength and flowability parameters are evaluated together. (C) 2017 Elsevier Ltd. All rights reserved.
Usability of Fuzzy Logic Modeling for Prediction of Fresh Properties of Self-Compacting Concrete
(Polish Acad Sciences Inst Physics, 2017) Beycioğlu, Ahmet; Gültekin, Adil; Aruntaş, Hüseyin Yılmaz
The aim of this study is to investigate the usability of fuzzy logic modelling for prediction of fresh properties of self-compacting concrete. In the modelling process, the percentage of fly ash and the percentage of granulated blast furnace slag, as replacement of cement, the percentage of micronized calcite, as replacement of total aggregate, were used as inputs. The slump flow diameter and time and also the V-funnel time were used as outputs. Results show that fuzzy logic modelling may be a useful approach to predict fresh properties of self-compacting concrete, containing fly ash, granulated blast furnace slag and micronized calcite.
The Effect of Polymer-Cement Stabilization on the Unconfined Compressive Strength of Liquefiable Soils
(Hindawi Publishing Corporation, 2013) Ateş, Ali
Soil stabilization has been widely used as an alternative to substitute the lack of suitable material on site. The use of nontraditional chemical stabilizers in soil improvement is growing daily. In this study a laboratory experiment was conducted to evaluate the effects of waterborne polymer on unconfined compression strength and to study the effect of cement grout on pre-venting of liquefiable sandy soils. The laboratory tests were performed including grain size of sandy soil, unit weight, ultrasonic pulse velocity, and unconfined compressive strength test. The sand and various amounts of polymer (1%, 2%, 3%, and 4%) and cement (10%, 20%, 30%, and 40%) were mixed with all of them into dough using mechanical kneader in laboratory conditions. Grouting experiment is performed with a cylindrical mould of 150 x 300 mm. The samples were subjected to unconfined compression tests to determine their strength after 7 and 14 days of curing. The results of the tests indicated that the waterborne polymer significantly improved the unconfined compression strength of sandy soils which have susceptibility of liquefaction.
Structural behavior of rammed earth walls under lateral cyclic loading: A comparative experimental study
(Elsevier Sci Ltd, 2017) Arslan, Mehmet Emin; Emiroğlu, Mehmet; Yalama, Ahmet
Rammed earth is one of the oldest masonry construction techniques such that there are many ancient structures built of rammed earth still existing. Recently, applications Of rammed earth are encountered more often, due to its ecological advantages such as renewability, sustainability, environmental protection, insulation and use of environmentally-friendly materials. Although it has been widely used in masonry construction, knowledge related to behavior of these structures or structural members is limited. Under this circumstance, in this study, behaviors of stabilized and non-stabilized rammed earth walls were investigated comparatively with masonry brick and aerated concrete walls. For this purpose, non-stabilized, 10% cement stabilized, 10% cement stabilized with 1% glass fibers and 5% cement stabilized with 5% blast furnace slag mixtures were produced in dimensibns of 20 cm x 150 cm x 150 cm rammed earth walls. Cyclic behaviors of the rammed earth walls were compared with masonry brick and aerated concrete walls with the same dimensions by using hinged loading test set-up. Structural properties such as load carrying capacities, total energy dissipation and stiffness degradation of the masonry walls were determined by utilizing the results of cyclic loading tests. At the end of the study, it was concluded that rammed earth wall stabilized using 10% cement showed the best structural performance. Surprisingly, performance of masonry brick wall fell behind of other masonry walls, even though it is the most commonly used material in masonry constructions. (C) 2016 Elsevier Ltd. All rights reserved.

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