Şemsettin Kilinçarslan

Investigating Radiation Shielding Properties of Different Mineral Origin Heavyweight Concretes

The radiation although has hazardous effects for human health, developing technologies bring lots of usage fields to radiation like in medicine and nuclear power station buildings. In this case protecting from undesirable radiation is a necessity for human health. Heavyweight concrete is one of the most important materials used in where radiation should be shielded, like those areas. In this study, used heavyweight aggregates of different mineral origin (Limonite, Siderite), in order to prepare different series in concrete mixtures and investigated radiation shielding properties. The experimental results on measuring the radiation shielding, the heavyweight concrete prepared with heavyweight aggregates of different mineral origin show that, are useful radiation absorbents when they used in concrete mixtures.

Determination of Radiation Shielding of Concrete Produced from Portland Cement with Boron Additives

Concrete is a material which is widely used for neutron shielding in such building constructions as nuclear power stations, particle accelerators and medical hospitals. Concrete is very significant for neutron shielding, because is contains some elements which help to moderate very penetrative fast neutrons. Boron increases the neutron shielding effectiveness of concretes. Boron can be added to concrete in different ways, by addition of boron to the water, used in concrete, or by addition of boron containing natural minerals. In this study, three samples of concrete were produced using B2O3 additives material, boron-modified active belite and Portland cement. Neutron absorption coefficients of the produced three different types of concrete samples were obtained through experiments. It is concluded that the addition of boron to concrete is an alternative option to be used for the purposes of neutron shielding.

POMZA AGREGALI KÖPÜK BETONLARIN ÖZELLİKLERİNİN ARAŞTIRILMASI

Volkanik faaliyetler sonucu olusan pomza, gozenekli ve iceriginde kristal suyu yer almayan bir kayactir. Gozenekli olmasi sebebiyle kullanildigi alanlarda, isi ve ses gecirgenligi yonunden avantaj saglamaktadir. Ayrica gozenekli oldugu icin de hafiftir. Pomzanin hafif olmasi, isi ve ses yalitim ozelliklerinin iyi olmasi nedeniyle insaat sektorunde cesitli yapi malzemelerinin uretiminde kullanim alani bulmaktadir. Buna ragmen, pomzanin insaat sektorunde yaygin kullanilan geleneksel yapi malzemelerine gore kullanim orani oldukca azdir. Bunun sebeplerinden biri ise ulkemizde bulunan bu dogal kaynakla ilgili yeterli akademik calismalarin olmamasidir. Bu calisma kapsaminda; Isparta, Kayseri, Nevsehir ve Karaman pomzalari kullanilarak kopuk beton uretilmistir. Ayrica, pomza agregasi yerine tas unu (kirectasi) kullanilarak kontrol betonu da uretilmistir. Toplamda deneysel uygulamalar icin 5 farkli kopuk beton uretimi yapilmistir. Uretilen kopuk beton numunelerinin birim hacim kutle, basinc dayanimi, isi iletkenlik katsayisi, ses yutma katsayisi ve ses iletim kaybi degerleri belirlenmistir.

Usage of chromite wastes as aggregate in foam concrete production

The rapidly developing mining sector in recent years has also brought environmental problems together. At the beginning of these problems are mine process wastes produced in high quantities from mines every year. The waste material at 90% and the concentrate chromite at 10% are obtained in the chromite ore enrichment plants. This significant amount of waste creates pollution in nature visually and physically. The aim of the study is to determine the advantages of using foamed concrete as a building material, to reduce the production cost of foamed concrete, to produce alternative solutions for rehabilitation, and to eliminate environmental pollution. The chromite enrichment wastes obtained from Fethiye, Köyceğiz, Denizli and Burdur regions were used as aggregates in the production of foamed concrete. In this study, compressive strength experiments were carried out according to TS EN 1354, thermal conductivity experiments were carried out according to TS EN 12664. As a result, it has been observed that chromite waste (dunite) can be used in the production of foamed concrete under certain conditions.

A new approach to compressive strength assessment of concrete: Image processing technique

In this study, the compressive strength levels of different concrete classes were estimated using an image processing technique. A series of different concretes were prepared by applying different water/cement ratios. The percentages of cement matrix, aggregate, and air void were calculated by processing the images obtained from the surfaces of hardened concretes. The relation between the parameters that were calculated via image processing and the compressive strengths of the concretes produced were examined. By this means, the compressive strength levels of concretes were estimated one by one via the developed image processing software and ImageJ. It was found that the compressive strength levels of concretes can be estimated with a high level of correlation by using the values obtained via the image processing technique. The developed software can be used to estimate the compressive strength levels of concretes. In addition, in considering concrete age, cure conditions, and relative humidity, the metho...