It is known that, especially in Turkey, many existing reinforced concrete buildings constructed in pre 1998 era, have many structural faults, due to deficiencies both in seismic code of the time and in application process. The column-beam regions are subjected to the high shear stresses under the seismic forces. And thus causing sudden failures since the required mode of failure is not accomplished. In this research, seismic behavior of beam column joint which is designed according to the old seismic code of Turkey is investigated experimentally, and then the damaged specimen is repaired by chemical epoxy and re-tested. As a conclusion, significant improvement is obtained in lateral load-drift behavior, stiffness degradation and energy dissipation capacities of repaired specimen.

Thanks to significant advances in materials science, researchers have managed to fabricate and develop different types of concrete proportional to application of new concrete technologies, such as high strength concrete (HSC) and foam concrete. The current paper presents the results of in experimental studies on foam concrete and its application. In addition, the effect of various parameters such as cement content, Water/Cement ratio as well as application of additives has been studied in mix design. In HSC, interaction between concrete constituent materials plays an important role in mechanical properties and compressive strength of concrete. Therefore, an appropriate understanding of these factors helps us select the suitable type and amount of materials in order to make a concrete with desirable behavior and strength. The methods and theoretical procedures used in the study is based on the ACI codes. This study aims to investigate the effect of using Micro Silica and plasticizer on strength of HSC. Based on the obtained results, the optimum percentage used for concrete mix design and positive effects of these materials on concrete property were confirmed.

In this study, the development of hydration of Portland cement and trass substituted cements containing super plasticizer was investigated. The effects of super plasticizer and trass substitution on the compressive strength, water demand, volume expansion and setting time was determined by the experiments the standard cement. Cement pastes were prepared with Portland cement and trass containing super plasticizer were performed using X–Ray diffraction, Fourier transform infrared spectroscopy and Simultaneous thermal analysis in order to determine their the phases developed during the hydration. Furthermore, microstructures by scanning electron microscope 28-days of hydration of cement pastes were determined and cement mortars were examined with strength tests. As a result, with the amount of trass, water needs and setting time have increased and volume expansion values remained between the standards. Also, the amount of Ca(OH)2 which is formed during the reaction was decreased. All these differences influenced the compressive strength of mortar samples.

Design codes aim to prevent shear failure of reinforced concrete (RC) beams since it is a brittle failure. An accurate prediction of shear strength is important for a proper design of an RC beam. There exist various equations for predicting the shear strength of RC beams. With increasing computational power, it is possible to develop numerical models delivering more accurate predictions than those equations do. In this paper, an artificial neural network (ANN) model developed for predicting the shear strength of RC slender beams without shear reinforcement is presented. The comparisons of the model with five design code equations and fourteen equations proposed by various researchers are given. The model has a better performance than the considered equations do in predicting the shear strength of the beams considered in this study. A parametric study conducted for investigating the effects of various parameters on the shear strength of RC slender beams without shear reinforcement by using the ANN model is also presented. A significant size effect on the shear strength of RC slender beams without shear reinforcement is observed through the results of the parametric study.

The main purpose of this study is to investigate the effect of basalt fibers on mechanical properties and fracture behavior of ordinary concrete. For this purpose, 15 notched concrete beams measuring 50x100x480 mm were prepared and tested using three point bending test in accordance with RILEM TC 50-FMC. Mixtures were produced using basalt fibers of 24 mm length at contents of 0.5, 1, 2, and 3 kg/m3 in addition to the mixture without fiber for comparison. Fracture energies were calculated using the area under the Load-Crack Mouth Opening Displacement (CMOD). The results obtained from the tests indicate that basalt fibers have considerably increased the fracture energy of ordinary concrete. However, it was observed that the addition of basalt fibers had no significant effect on the compressive strength and elastic modulus. It was also observed that the splitting tensile and flexural strengths began to decrease beyond a fiber content of 2 kg/m3. Overall evaluation indicated that addition of 2 kg/m3 basalt fibers to the mixture seems to be proper in relation with the properties tested in this work.

Calculation of the moment capacity of reinforced concrete (RC) shear walls is a hard and time consuming task since they have more reinforcement rows. Although there exist some software to overcome this difficulty, those software require some expense. In this study, a simple equation is proposed to calculate the moment capacity (Mr) of rectangular RC shear walls which are designed according to the 2007-Turkish Earthquake Code. The proposed equation is simple because it includes variables which are easy to determine such as length and thickness of the shear wall, reinforcements in the boundary member at the tension zone and the axial load level. Moment capacities from the proposed equation are found to be very close to the ones from the detailed analysis. Using the proposed equation, charts for the moment capacity (Mr) of rectangular RC shear walls having varying dimensions and varying reinforcement ratio were developed and given in the appendix.

In this study, performance of meta-heuristic methods on optimum design of reinforced concrete (RC) retaining wall has been investigated with respect to minimizing the cost and the CO2 emission. Biogeography Based Optimization (BBO) and Social Spiders optimization (SSO) methods utilized for investigation. The minimizations of the cost, the CO2 emission and multi-objective of the cost+CO2 functions are described as objective functions of the optimization problem. There are thirteen design variables are defined in the optimization problem. Eight of these variables are the cross sectional dimensions of the retaining wall. The other five design variables are the reinforcement detailing of wall members. Flexural and shear strength requirements, minimum and maximum cross section areas of the reinforcement bar, the requirement length for reinforcement details and the factor of safety for failure modes are defined as constraints functions of the optimization problem. The Flexural and shear strength requirements, minimum and maximum limitations of the reinforcement bar areas are adopted from American Concrete Institute (ACI 318-14) design code. In order to test performance of the presented optimization methods literature design examples are used. In addition, efficiency of steel and concrete classes on optimum CO2 emission and cost have been investigated by using different steel and concrete classes.

Drought is one of the most important natural disasters. The main aim of the present study is to investigate the applicability of the Apportionment Entropy (AE) as a drought index. For this purpose, the Standard Precipitation Index (SPI) and the AE method as a drought indices were investigated and compared for monthly precipitation data in Northern Aegean Region. In the presented study, 29 gauging stations with long term observations are evaluated in Northern Aegean Region. The results of the study showed that PE method can be used as a drought index and the analysis of drought results contributed to the identification of drought periods for the Northern Aegean Region.

Recently, gene expression programming (GEP) have been widely used to model the human activities in many areas of civil engineering applications. In this study, the GEP models for predicting the compressive strength of concretes containing metakaolin and silica fume have been used at different days. In order to building these models, the experimental results of 195 specimens produced with 33 different mixtures were gathered from the literature. The input data used in these models have been arranged as eight parameters that cover the age of specimen and the amounts of concrete mixtures. According to these input parameters, the compressive strength values of concretes containing metakaolin and silica fume at different days are predicted in these models. The training and testing results of models have shown that GEP technique has strong potential for predicting the compressive strength values of concretes containing metakaolin and silica fume at different days.

In this study, the effects of the mixture in different proportions on the physical and mechanical properties of hardened materials produced with diatomite (D) hydrophobic clay (HK) and cement (PC) were investigated at the prefabricated structural element production. For this purpose samples were prepared using cement rate of 10%, 20% and 30% and hydrophobic clay rate of 5%, 10% and 15% replacement of diatomite weight. The physical and mechanical properties of samples were tested after pressure is applied and 24 hours of steam curing. The combination of diatomite and hydrophobic clay produced samples with unit weight and compressive strength values of 1000-1300 kg/m3 and 4-18 MPa, respectively. Compared with conventional building materials of the products produced it was determined to have similar physical and mechanical properties.

In this study, it is investigated effect of construction waste to some engineering properties of a high plasticity clay. For this reason, some chemical properties of the soil sample and construction waste are determined. The consistency limits and standard compaction tests are carried out on the clayey samples in weight with the ratios 2%, 5%, 10%, 15%, 20%, 25%, 30% and 35% of the construction waste passing from the sieve of No 40. The constant-volume swelling and unconfined compression tests are also conducted on both pure clay and the mixtures in weight with the ratios 5%, 10% 20% and 30% of the construction waste compacting at the optimum water content and maximum dry density. From the results of test, it is found that the construction waste can be effectively used at a ratio of 10%-20% for both decreasing the swelling potential of clay and increasing the unconfined compression strength of that.

A modern highway must be capable of proving traffic safety, comfort to passenger cars as well as efficient and economical transportation. In view of the increase in the number of traffic accidents due to the developments in automotive industry, the traffic safety has gathered too much consideration in recent years among the other factors. In order to provide safety traffic conditions, the friction resistance between the vehicle tire and pavement surface should be in certain level. The surface of a highway on the other hand must provide enough adherences between the thread of the tire and the road surface enabling the cars to stop in safety way in case of application of the brakes. Especially in rainy climate conditions, the friction resistance in question decreases to very small values. The researches in this field point out that the decrease in the value of friction increases the rate of traffic accidents. Therefore in order to determine the friction resistance, the surface properties of the road must be evaluated periodically. The mean surface texture depth of the road on the other hand must be evaluated with the frictional characteristics. In this work, the mean texture depth characteristics were determined with every three months period by the sand path test and also the dynamic friction test was also applied to evaluate the frictional characteristics of the slurry seal applied road sections in Ýzmir. The gathered data together with the traffic characteristics were linked with the traffic accident date obtained from Security General Directorate of Izmir in order to build various models. In conclusion, the importance of the road surface texture on traffic safety of was also discussed.

Many methods are used to improve the engineering properties of the soils. While the some of the developed methods cannot produce an effective solution, some of them are not economical for practical solution. In this study, permeability and shear strength behaviors of natural kaolin, bentonite and sand mixtures have been investigated in the presence of three different biopolymers (xanthan gum, chitosan and chitin) and different concentrations (0.25-0.50-0.75 and 1%). The results have shown that, the xanthan gum and chitosan addition decreased the permeability coefficient almost 30 hold. While the biopolymer effect on shear strength behavior is investigated, 1% xanthan gum and chitosan concentration addition provided 15-10% increase in angle of internal friction. The obtained test results have shown that, biopolymers can be used in dams and landfills at impermeable clay liner applications.

In this study, tetracycline and degradation products were determined in the basins of a trout farm and in the stream carrying the waters of trout farm. Tetracycline (TC), 4-epitetracycline (ETC), 4-epianhydrotetracycline (EATC) and anhydrotetracycline (ATC) concentrations were determined under the detection limit in upstream of trout farm. The highest and lowest tetracycline concentrations detected in trout farm are 7.64±0.38 ppb and under detection limit, respectively. The highest and lowest 4-epitetracycline concentrations were 16.2±0.8 and 1.85±0.09 ppb, respectively while the highest and lowest 4-epianhydrotetracycline concentrations detected in trout farm were 25.8±1.3 and 6.12±0.30 ppb, respectively. The highest and lowest anhydrotetracycline concentrations detected in trout farm were 18.5±0.9 and 6.24±0.31 ppb, respectively. Mean tetracycline, 4-epitetracycline, 4-epianhydrotetracycline and anhydrotetracycline concentrations were 3.52±0.17; 5.30±0.26; 14.4±0.7 and 9.64±0.48 ppb in downstream of trout farm. When upstream and downstream were compared in terms of tetracycline and degradation products it could be said that Keban stream was affected as a result of activity of trout farm.

In this study operating pressure driven systems which is known their efficiency in literature, for paper and pulp industry wastewaters in batch conditions were executed by using NFloose/NFtight membrane combination. The batch NFloose/NFtight experiments were respectively applied at 12 and 20 bars by conventional membrane filtration process, at a stirring rate of 300 cycle/min, at pH 10 and at a temperature of 25 °C. Determination of most suitable membrane at batch operating conditions were made by using 8 different membranes (for NFloose NP010, NFG, MPF36 and CK3001 and for NFtight NP030, NF270, DS-5DK, ESNA) through organic matter removal and filtrate flux values. In NFloose membranes at a filtrate flux of 4.12 L/m2 h removal of 61.0% TOC and 76.9% COD and MPF36 membrane was determined to be best NFloose membrane. The filtrate water obtained by MPF36 were later passed through NFtight membranes. In all NFtight membranes generally the organic matter removal efficiency was good and ESNA was selected to be the best membrane in terms of effluent quality by obtaining organic matter removal at rates of 93.9% TOC and 94.2% COD with 10.05 L/m2 h filtrate flux. From this point of view, in short term operation of paper wastewaters by pressure driven NFloose/NFtight integrated membrane system, it was seen that good quality of outlet water with 7.15 pH and a conductivity coefficient of 144 µS/cm and at 13 mg/L TOC and 28 mg/L COD concentrations could be obtained also that good quality of reuse water could be produced in terms of aimed effluent water.

Arsenic occurs naturally in the earth’s surface and is widely distributed in the environment. Arsenic is commonly encountered in groundwater in different parts of the world due to natural processes as well as from anthropogenic activities. Groundwater and surface water contamination by arsenic has been reported from many countries including Turkey. Chronic health effects of arsenic are lesions (spotted keratosis, melanosis, dorsal keratosis, hyper pigmentation, hyper keratosis and gangrene). Long-term exposure to arsenic may cause bladder, lung, skin, kidney, liver and prostate cancer. Due to the high toxic effects on the human health, the maximum contaminant level of arsenic in drinking waters was limited to 10 µg/L by the United States Environmental Protection Agency and World Health Organization. Arsenic level in drinking water was established as 10 µg/L in 2008 in Turkey. Arsenic-contaminated groundwater is also used for irrigation for the growing plants and livestock watering as well as the use of drinking water sources. Contaminated water, used in irrigation, could cause dangerous conditions in soil and product quality. Elevated arsenic levels in irrigation water were found to inhibit seed germination and seedling establishment of crops. A number of studies have reported a large variability in arsenic levels in foods, waters, and soils from different countries. Animals can accumulate arsenic via intake of contaminated feed, soil, water and then these animal tissue containing residues of arsenic can be harmful to human health who consumes the meat, visceral organs, and milk. Arsenic accumulation differs between plant species and individuals. The results showed that the trend of arsenic concentration in the plant tissues are root>stem>leaf/fruit. Concentration of arsenic in plants is much higher than the soil and water and it has toxic effects to the other organisms. In this review article accumulation of arsenic in plants and harmful effects on the human health are evaluated.

Chlorine which is nowadays the most commonly used disinfectant, interacts aquatic organic matter and causes formation of harmful disinfection by products. For this reason, number of researches on chlorine dioxide as a disinfectant alternative to chlorine, increased in recent years. After disinfection via the chlorine dioxide, chlorite and chlorate which defines as inorganic by products are formed. Chlorite total maximum concentration in water is limited as 1 mg/L as by USEPA. WHO limits total maximum chlorite concentration as 0.7 mg/L in water. There is no detailed study has been conducted for determination of the limit value yet in our country. In this study; after 0.25;0.50;0.75;1;1.25 and 1.5 mg/L chlorine dioxide had been dosed to Ömerli raw water samples taken in December, and February; disinfection by products: chlorite, chlorate, THMs, HAAs and water quality parameters such as TOC, chloride, floride, bromide, sulphate and nitrate were analyzed and effect of the pH and contact time also investigated.

In the last century, the demand for new settlement areas increases continuously due to highly population and migration. Throughout history, the erroneous selection of a settlement location has led to large-scale disasters. In particular, earthquakes such as 1999 Marmara and 2011 Van have caused the loss of many lives and damage that cost millions of dollars. The destruction caused by earthquakes shows that the existing settlement plans do not attach sufficient importance to soil properties. In this study, liquefaction potential of the Aksaray city was evaluated using Geographical Information Systems (GIS) techniques depend on geotechnical and hydrogeological data. The 58 soil samples were collected from geotechnical drilling to investigate the soil characteristics of study area. The Tokimatsu-Yoshimi method was used to determine the liquefaction potential. To determine the liquefaction risk, earthquake scenarios with different magnitudes were simulated and maximum horizontal ground accelerations were calculated. The spatial distribution maps of liquefaction risk were created using the kriging interpolation method and exponential variogram model. It was seen that areas with high liquefaction risk were concentrated on the northwestern and southeastern regions of the city. The results of this study can be used by urban and regional planners as a guide in the selection of safe settlement areas. Furthermore, the use of the liquefaction maps will reduce human and economic losses due to natural disasters.

In this study, geological, hydrogeological and hydrogeochemical characteristics of the Tavþanlý (Kütahya) and its surroundings were investigated in detail. The rock units are observed with different age and lithology in the Paleozoic-Quaternary periods of time in the study area. The most important surface water and groundwater reservoirs are Orhaneli river and alluvium, limestone and tuff units, respectively. In the region groundwater level ranges from 1.5 m to 25 m. While groundwater flow direction is towards the west in the east of the plain; it is towards the northeast in the southern part of the plain. In order to determine hydrogeochemical features of the water resources, hydrochemical analyses of the surface water and groundwater samples were performed. According to the obtained results, water resources are Ca-Mg-HCO3, Mg-HCO3 and Na-HCO3 facies.

Accessible resource base of the Simav Geothermal field, one of the high temperature field in western Anatolia, was estimated using the volumetric method together with Monte Carlo simulation. The main geothermal reservoir in the field hosted in metamorphic rocks having secondary permeability enhanced due to intense tectonic activity. The highest bottom-hole temperature at the field was recorded as 162.4 °C in the EJ-1 having depth of 725 m penetrating metamorphic rocks of Menderes Massif. At the application stage of the volumetric method physical parameters, such as area thickness, temperature, etc., related to geothermal reservoir were determined by Monte Carlo simulation in the context of probability density distributions. For this purpose, an Excel VB application that generates random values corresponding to the probability distribution for each parameter was created. Using a lognormal distribution for porosity and triangular distributions for reservoir thickness, area and temperature, the most likely accessible resource base of the Simav Geothermal Field was calculated as 1.3x1015 kJ. The probability to achieve this value was calculated as 67%. The same simulation results the mean and the most likely electricity generation potential of Simav geothermal field as 26 MW and 19 MW, respectively. The probability of electrical generation capacity of 19 WM was calculated as 71%. Mass flow rate that should be supplied to the power plant of 19 MW was calculated as 1204 tones/hour (334 L/s).