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Akcanca F.,General Directorate of State Hydraulic Works | Aytekin M.,University of Bahrain
Environmental Earth Sciences | Year: 2014

In this study, an investigation was performed to determine if lime-stabilized sand-bentonite mixtures are appropriate for the construction of sanitary landfills liners. For this aim, the hydraulic conductivity tests were conducted in the laboratory on sand-bentonite mixtures and lime-stabilized sand-bentonite mixtures to evaluate the effect of wetting-drying cycles. The hydraulic conductivity tests were performed to see if their hydraulic conductivities are affected by wetting-drying cycles. First series of specimens have been prepared as a mixture of sand and bentonite only. In the first series of specimens, sand was mixed with bentonite in proportions of 20, 30, 40, and 50 %. In the second series of the specimens, lime in proportions of 1, 2 and 3 % by weight was added to the mixtures of sand-bentonite in proportions of 20, 30, 40, and 50 %. From the results of the tests, it was observed that while optimum water content increased, maximum dry density decreased with addition of lime to the sand-bentonite mixtures. Generally, the hydraulic conductivity increased with the addition of lime to the mixtures but at low percentages of lime (1-2 %), however, slight decreases in k were recorded. It was also observed that the wetting-drying cycles on the permeability test indicate cure effect on specimens with addition of lime which resulted in decreased the hydraulic conductivity. © 2013 Springer-Verlag Berlin Heidelberg.

Sengul C.E.,General Directorate of State Hydraulic Works | Aksoy A.,Eurasian University | Iskender E.,Karadeniz Technical University | Ozen H.,Florida International University
Construction and Building Materials | Year: 2012

The aim of study is to evaluate rutting with Marshall Quotient (MQ) and repeated creep (RCT). Three hydrated lime (HL) mixtures were evaluated and compared with control mixtures (CMs) for conditioned samples (CSs). Filler was reduced and HL was substituted at 2%, 4% and 6%. Damage system (ECS) based on moisture was applied. For rutting with MQ approach also some mixtures were produced including SBS and HL. Modified and synergistic (SBS and HL) mixtures were interrogated. An observed damage level was exposed with the selected ECS. RCT was quite effective at different HL ratios for HL efficiency for dense gradation. HL was found beneficial due to moisture. Increasing of HL from 2% to 6% deformation resistance increased. Tertiary deformation was not revealed at 64,730 pulses for CM and HL ones. Expected results were obtained with the RCT for both HL mixtures and also SBS. MQ is not a good indicator of the deformation resistance because of the larger intervals between CM and others. © 2011 Elsevier Ltd. All rights reserved.

Aydogan D.,General Directorate of State Hydraulic Works | Aydogan D.,Karadeniz Technical University | Kankal M.,Karadeniz Technical University | Onsoy H.,Karadeniz Technical University
Journal of Flood Risk Management | Year: 2016

In this paper, a regional flood frequency analysis of Çoruh Basin was performed with the L-moments method. Because the area of Çoruh Basin is large (21100km2), and the climatic, hydrologic, and topographic characteristics vary throughout the basin, it was divided into four sub-regions for examination. Discordancy measure tests were performed for the sites located in each sub-region. The H heterogeneity test was carried out by performing 500 simulations with the Kappa probability distribution for the homogeneity of the region. With the help of a diagram of the L-moment ratios and by administering the Z goodness-of-fit measure test, the appropriate distribution was determined for each sub-region. The distributions were used to identify the quintiles according to various probabilities of non-exceedance. The accuracies of the estimated measured for the regional growth curves and quantiles were calculated using Monte Carlo simulation. Finally, the flow values determined from the quantiles estimated with the L-moments method were compared with those estimated previously with an at-site frequency analysis (Gumbel distribution) on the basin master plan for four large dams in the Çoruh Basin. © 2014 The Chartered Institution of Water and Environmental Management (CIWEM) and John Wiley & Sons Ltd.

Sengul C.E.,General Directorate of State Hydraulic Works | Oruc S.,Karadeniz Technical University | Iskender E.,Karadeniz Technical University | Aksoy A.,Eurasian University
Construction and Building Materials | Year: 2013

The purpose of this study is to research SBS polymer modified stone mastic asphalt (SMA) pavement performance. With this scope Marshall test (ASTM D1559) test was verified and optimal bitumen contents were calculated with experimental stages. At the optimal bitumen content control and SBS SMA mixtures were evaluated with Marshall Quotient (MQ) approach, repeated creep test (RCT), indirect tensile strength test (ITST), Laboratoire Central des Ponts et Chaussees (LCPC) Wheel tracking tests. According to the MQ results SBS modified samples gives higher values than conventional control mixtures. Higher MQ can be thought as more resistance to the plastic deformation. Controversial results can be obtained with MQ approach for some types of asphalt mixture gradations. Because of structural integrity and stone on stone contact gradation for SMA MQ approach gives more harmonious results. Efficiency of SBS polymer was confirmed with MQ method. Modified samples gave higher indirect tensile strength than control ones. RCT and LCPC wheel tracking test results shows that SBS modified mixtures have lower rutting values than the conventional mixtures. © 2013 Elsevier Ltd. All rights reserved.

Bayram A.,Karadeniz Technical University | Kenanoglu M.,General Directorate of State Hydraulic Works
Lake and Reservoir Management | Year: 2016

Bayram A, Kenanoğlu M. 2016. Variation of total suspended solids versus turbidity and Secchi disk depth in the Borçka Dam Reservoir, Çoruh River Basin, Turkey. Lake Reserv Manage. 32:209–221. We evaluated the influence of a hydropower dam, Borçka Dam, on the total suspended solids (TSS) carried by the Çoruh River and Murgul Stream, northeast Turkey, by studying its variation versus nephelometric turbidity. The impact of discharge from the copper mining facility to the Murgul Stream draining into the Borçka Dam Reservoir was also evaluated. In situ turbidity monitoring, Secchi disk transparency, reservoir water depth measurements, and surface water sampling were conducted monthly at 12 stations from December 2010 to November 2011. TSS carried by the Çoruh River and Murgul Stream showed 3 different deposition behaviors based on the reservoir water levels. On an annual basis, the TSS carried by the Çoruh River was 371 mg/L and the turbidity was 332 NTU, whereas the TSS carried by the Murgul Stream was 16,992 mg/L and the turbidity was >712 NTU. Based on the TSS of 41 mg/L and the turbidity of 46 NTU measured at the outlet of the Borçka Dam and hydroelectric power plant, we concluded that the Borçka Dam could trap a large portion of the TSS and could reduce turbidity considerably because of its long hydraulic residence time, and thus reduce possible silting in the downstream reservoir. © 2016, © Copyright by the North American Lake Management Society 2016.

PubMed | General Directorate of State Hydraulic Works and University of Frat
Type: | Journal: Journal of environmental management | Year: 2016

Determination of the effect of physicochemical parameters on the removal of tetracycline (TC) and degradation products is important because of the importance of the removal of antibiotics in Wastewater Treatment Plant (WWTP). Therefore, the purpose of this study was to investigate the relationships between removals of TC and degradation products and physicochemical parameters in Municipal Wastewater Treatment Plant (MWWTP). For this aim, (i) the removals of physicochemical parameters in a MWWTP located in Elaz city (Turkey) were determined (ii) the removals of TC and degradation products in MWWTP were determined (iii) the relationships between removals of TC and degradation products and physicochemical parameters were investigated. TC, 4-epitetracycline (ETC), 4-epianhydrotetracycline (EATC), anhydrotetracycline (ATC), and physicochemical parameters (pH, temperature, electrical conductivity (EC), suspended solids (SS), BOD5, COD, total organic carbon (TOC), NH4(+)-N, NO2(-)-N, NO3(-)-N and O-PO4(-3)) were determined. The calculation of the correlation coefficients of relationships between the physicochemical parameters and TC, EATC, ATC showed that, among the investigated parameters, EATC and SS most correlated. The removals of other physicochemical parameters were not correlated with TC, EATC and ATC.

Uyanik O.,Suleyman Demirel University of Turkey | Ekinci B.,General Directorate of State Hydraulic Works | Uyanik N.A.,Suleyman Demirel University of Turkey
Journal of Applied Geophysics | Year: 2013

This study analyzes liquefaction in the Kumluca/Antalya residential area and surroundings, using seismic velocities of soil deposits and the predominant period of the earthquake wave. The liquefaction analysis calculates shear-stress ratio, shear-resistance ratio and safety factor. Shear wave velocity used in liquefaction analysis was determined through surface waves. Moreover, the dynamic parameters of the ground were calculated through seismic velocities. Distributions of groundwater, shear wave velocity, adjusted shear wave velocity, predominant period of vibration, soil amplification and ground acceleration of the research area were mapped. In addition, the liquefied and non-liquefied areas as a result of liquefaction analysis in Kumluca were determined and presented as maps. Examining these maps, among all these maps, the limits of the lagoon sandbar and the old lake area were determined using only the liquefaction map. © 2013 Elsevier B.V.

Topal M.,General Directorate of State Hydraulic Works | Arslan Topal E.I.,Firat University
Environmental monitoring and assessment | Year: 2015

The aims of this study are to investigate the fate of tetracycline (TC) and degradation products (DPs) in municipal biological wastewater treatment plant (MBWWTP) located in Elazığ City (Turkey) and to determine the occurrence and transport of TC and DPs in surface water (SW) (Kehli Stream) which the effluents of the plant discharged. The aqueous phase removal of TC, 4-epitetracycline (ETC), 4-epianhydrotetracycline (EATC), and anhydrotetracycline (ATC) in the studied treatment plant was 39.4 ± 1.9, 31.8 ± 1.5, 15.1 ± 0.7, and 16.9 ± 0.8%, respectively. According to the analyses' results of SW samples taken from downstream at every 500-m distance, TC and DPs decreased by the increase in the distance. In downstream, at 2000 m, TC, ETC, EATC, and ATC were 4.12 ± 0.20, 6.70 ± 0.33, 8.31 ± 0.41, and 3.57 ± 0.17 μg/L, respectively. As a result, antibiotic pollution in the SW that takes the effluent of MBWWTP exists.

Topal M.,General Directorate of State Hydraulic Works
Ecological Engineering | Year: 2015

In this study, tetracycline (TC) and degradation products in Phragmites australis grown in Kehli stream carrying municipal wastewater treatment plant effluents were determined. P. australis plants are spread along Kehli stream. The concentrations of TC and degradation products were determined in roots, stems and leaves of the plants. Maximum TC, 4-epitetracycline (ETC), 4-epianhydrotetracycline (EATC) and anhydrotetracycline (ATC) concentrations were 31.5 ± 1.5, 46.1 ± 2.3, 27.0 ± 1.3 and 16.5 ± 0.8. ppb, respectively in roots while 8.3 ± 0.4, 9.99 ± 0.49, 6.6 ± 0.3 and 4.69 ± 0.23. ppb, respectively in stems. Maximum TC, ETC, EATC and ATC concentrations were 4.74 ± 0.23, 5.58 ± 0.28, 2.96 ± 0.15 and 3.71 ± 0.18. ppb, respectively in leaves. As a result, it was determined that P. australis plants uptake TC and degradation products. The decreasing uptake order of P. australis was determined as ETC. >. TC. >. EATC. >. ATC. © 2015 Elsevier B.V.

Arslan Topal E.I.,Firat University | Unlu A.,Firat University | Topal M.,General Directorate of State Hydraulic Works
International Journal of Recycling of Organic Waste in Agriculture | Year: 2016

Purpose: In waters and wastes, direct pathogen detection is difficult and time consuming. Therefore, coliforms are used as indicators to measure the presence of pathogens. Composts originated from extrements, sewage sludges and plant wastes those contact with manures may have potential health hazard to human. Therefore, the detection of coliforms both during composting and in the obtained composts is used to investigate the presence of pathogens for determination of the potential health risk. Methods: In this study, the effect of six different aeration rates on elimination of total and faecal coliform bacteria was investigated during in-vessel aerobic composting of vegetable–fruit wastes. Total coliform and faecal coliform numbers in the samples were measured by the most probable number method. Results: Coliforms significantly increased before the thermophilic stage except the faecal coliforms in the reactor which operated with the lowest aeration. The coliforms suddenly decreased after thermophilic stage in all reactors. Total coliforms reduced within the range of 78.2–99.9 % while faecal coliforms reduced within the range of 72.5–99.9 % after the thermophilic stage. At the end of the composting period (day 18), total coliforms and faecal coliforms reduced within the range of 99.9–100 %. Conclusions: Although all the aeration rates used in the present study were effective for the elimination of coliforms, the lowest faecal coliform number was seen in the reactor that had the lowest aeration rate. At the end of the study, the faecal coliform numbers in all reactors confirmed some limits for the application activities of composts. © 2016, The Author(s).

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