Gülgün Yılmaz

Utilization of Ceramic Wastes in the Construction Sector

Ceramic wastes causing a serious problem are polluting the environmental problem in Eskisehir Region, Turkey. In this paper, were studied three wastes, ceramic mud wastes (CMW), crushed ceramic tile wastes (CCTW) and ceramic tile dust wastes (CTDW). The waste reused as an alternative construction materials in the backfill material with lime, zeolite, and cement, and as a road sub-base material with natural soil, sand and crushed aggregate, and as a concrete block material with cement mixture, and as an improving expansive soil material with Na-bentonite. According to the results of these experiments, a remarkable decrease of zinc (Zn) was noted in the content of CMW from ceramic refinery plant and it was reused as a construction materials. CCTW were used for cement mixture production in substitution of aggregates with dosage of 175kg/m. Swelling pressure and swelling percent of Na-bentonite clay mixed with 40% CCDW decreased 86% and 57%, respectively.

Effect of curing time on selected properties of soil stabilized with fly ash, marble dust and waste sand for road sub-base materials

The properties of sub-base filling materials in highway construction are essential, as they can determine the performance of the road in service. Normally, the existing materials are removed and replaced with new materials that have adequate load-bearing capacity. Rising environmental concern and new environmental legislations have made construction professionals consider other methods. These methods include stabilizing the existing materials with other additives to improve their performance. Additives can be waste materials generated by different industries. In this work, the existing excavated soil is stabilized with waste materials. The wastes consisted of fly ash, marble dust and waste sand. The percentage addition of waste materials was 5%, 10%, 15% and 20% (by mass) of the existing soil. The soil/waste specimens were cured for 1, 7, 28, 56, 90 and 112 days before testing. Testing included the dry unit weight and unconfined compressive strength (qu) as well as X-ray diffraction analysis and scanning electron microscopy observation. Also, the California Bearing Ratio values were obtained and are reported in this investigation. The results showed that the qu values increased with the increase in waste materials content. Also, there is tendency for the dry unit weight to increase with the increase in waste materials.

Performance of Steel Slag and Fly Ash Added Soil as Subbase Materials

The steel industry, which is an indicator of the developed countries with its production, also brings the problem of waste together. This waste product, that differs depending on the production process and is called slag, is generally referred as solid waste. Many researchers to use for different purposes are examining this type of wastes, which are difficult to store and dispose. It is also investigated about the usability as a filling material in civil engineering. The possibility of using such materials as an alternative to soil stabilization solutions, especially in the areas close to the industries producing these wastes, in the filling of such structures as the roads, railways, airport runways comprise of the basis of the surveys. In this study, the impact of steel slag and fly ash, another waste product released because of combusting lignite coal with low energy at the power plants, on the bearing ratio after blending with kaolin grade clay at different rates was observed. Keeping the 5% clay rate stable in weight, steel slag and fly ash with varying rates were added to prepare the test samples, which were cured for 0, 7, 28 and 56 days under stable conditions and subjected to California Bearing Ratio tests. The results showed that when steel slag and fly ash are used with clay, there were significant increases in their bearing ratios compared to the reference clay sample. While the wet California Bearing Ratio (CBR) was around 15% for the normal clay sample, when it is blended only with steel slag the wet CBR increased up to 70%, and when blended with fly ash the wet CBR went up to 130%. The used materials had very weak and weak binding properties when used alone while their binding properties increased by gaining pozzolanic property within the mix.

The Importance of Geological Conditions’ Effects on Construction in Landscape Planning in Turkey

The development of the majority of the cities in Turkey from the point of urbanization were occurred without regard to the effects of the geological conditions of the region that were founded in the past. The settlement, transportation and industrialization greatly influence the natural environmental balance in a region. It is necessary to control the effects of such a development on the natural environment in order to prevent possible damage. For this reason, in addition to the social, cultural and economic conditions of the region, the geological and geotechnical conditions must be assessed very well. However, an urban development envisaged in such as principle may be a living city life with settlement, transportation and industrialization. It is an inevitable necessity and a responsibility at the same time to evaluate the geological structure of the ground, the geotechnical properties and the geological environmental conditions. The possible effects on the construction must be observed very well prior to the construction. The necessary precautions at the same time in the field of urban development are especially regarding the construction problems. In today’s urbanization, especially in the construction sector, the importance of geology can only be understand after the events such as earthquakes, floods, landslides, collapses and destruction, which are caused by geological reasons and property destruction caused by them. In this study, the place and importance of the effects of geological conditions in Turkey are investigated and the solutions tried to be proposed.

Bearing Capacity and pH Value of Stabilized Soils with Class F Fly Ash and Cement

The California Bearing Ratio (CBR) test determines behaviour of road sub-base and granular layers for flexible pavement. In the conventional CBR test, compacted sample was waited in air for 24 h and in water for 4 days. In this study, the fresh and 28 days curing effects were examined and pH values were measured end of 28 days curing on the CBR percent of soils stabilized with F class fly-ash and cement. There are two main matrix material in this study. One of the matrices consists of Bilecik Clay and Lime and other consists of Bilecik Clay, Bentonite and Lime. In samples, fly-ash (Class-F) and cement were used as additives. Different mixtures which were obtained with various combinations of these materials were prepared and end of compaction were cured in various moulds depending on test. The mechanical strength test as wet CBR, triaxial and unconfined strength tests were performed on the mixtures and physical characteristics as CBR percent and chemical characteristic as pH values were measured.

Effect of Particle Size Distribution on the Sintering Behaviour of Fly Ash, Red Mud and Fly Ash-Red Mud Mixture

In this study, the characterization and microstructure observation of the sintering behaviour of F (from Seyitomer Thermal Power Plant) and C (from Soma Thermal Power Plant) types fly ashes, red mud and red mud–fly ash mixtures at 4 and 8 h milling times with a mortar type ball are investigated. The particle size distribution (PSD) was carried out by laser technique. The PSD analysis revealed that the particle size decreased with increasing milling time. After milling, the samples were pressed into a cylindrical form without using any additive or binder. The formed samples were sintered at 1050 °C. Phase evolutions and microstructures of the formed samples were carried out by using X-ray diffraction method (XRD) and scanning electron microscope (SEM) method, respectively. The water absorption and compressive strength were tested to determine some physico-mechanical properties. The results of mineralogical analysis as well as the microstructural observations reveal that phase transformations occurred during the sintering treatments. The results showed that at the chosen optimum conditions (F type fly ash-red mud mixture with 1:1 ratio, sintering temperature of 1050 °C and milling time of 4 h), the best characteristics of sintered glass ceramic could be obtained. Values obtained from mechanical testing showed that the fly ash–red mud sintered ceramic materials had increased strength compared to other sintered ceramic materials. The sintered materials from red mud have the highest water absorption value.

An Overview of Urban Transformation Applications in Eskisehir (Turkey) After the 1999 Earthquakes

Cities transformed by their own socio-cultural, economic, political and technological processes from their existed period. An urban transformation project should be planned from a variety of angles such as physical, economic, social and environmental as well as legal, institutional, financial and partnerships to the implementation of the project, and transformation programs should be prepared. In urban transformation projects, it should aimed to develop strategies to restore economic viability in urban parts that have become physical and social depressions, thereby increasing urban welfare and quality of life should also be the other side of the concern. The construction sector is the locomotive sector of the economy all over the world, with the production and the employment provided by the dozens of sub-sectors attached to it. The Turkish construction sector has an important place in the development of the country. In recent years, urban transformation projects in our cities have progressed very rapidly. This process is taking place in Eskisehir after the 1999 earthquakes. However, there are many economic, social and legal problems in this process. In this study, the urban transformation applications in Eskisehir after the 1999 earthquake is evaluated and solution proposals are presented.

Mechanical and Microstructural Properties of Heated and Polluted Kaolinite and Bentonite

High temperatures and pollution due to the storage of nuclear wastes in deep soil influence the mechanical properties and microstructure of kaolinite and bentonite. In this study, 0.5 N CaCl2 and 2000 ppm ZnCl2 solutions were added to kaolinite(k) and bentonite(b) samples treated at different temperatures ranging between 100 and 600°C. After the preparation of the samples, particle size variation, consistency limits and unconfined compressive strength values of the clays were calculated by means of standard experiments. In addition, the pH level, electrical conductivity, salt and metal pollution of the samples were determined. Microstructural properties of the samples were analyzed by means of SEM. Experimental results revealed that heating and polluting the clays at 600 °C decreased the clay size fraction, the liquid limit and the plastic limit but increased the silt size fraction and unconfined compressive strength values. According to electrical conductivity (EC) values, the samples which contained ZnCl2 were natural clays, whereas those which included CaCl2 were saline clays. This work establishes the advantages of observing mechanical properties parallel with microstructure variations in order to understand the changes in the properties of clays.