Yüksek Lisans Tezi Görüntüleme

Öğrenci: Caner ARSLANTÜRK
Danışman: Prof. Dr. Şakir ERDOĞDU
Anabilim Dalı: İnşaat Mühendisliği
Enstitü: Fen Bilimleri Enstitüsü
Üniversite: Karadeniz Teknik Üniversitesi
Tez Adı: Retempering of Prolonged Mixed Concrete Mixtures Incorporating Fly Ash and Silica Fume by using a Superplasticizer
Tezin Türü: Yüksek Lisans
Kabul Tarihi: 25/1/2007
Sayfa Sayısı: 105
Tez No: i1790
Özet:

      Concrete mixtures with strength levels closed to concrete grade C25/30 were

produced. The concrete mixtures investigated were without mineral additive, with silica

      fume and with fly ash, respectively. The objective of this investigation was to measure and

improve the slump losses of concrete mixtures resulting from prolonged mixing by using a

      superplasticizer chemical admixture.

Each mixture was thoroughly mixed for five minutes to accomplish homogeneity

      and then slump, temperature, air content, and unit weight of the concrete mixture were

measured, respectively. Cube specimens of 15 cm were prepared for 28-day compressive

      strength measurement. At the end of each mixing period a certain amount of a

superplasticizer was used to restore the slump of concrete at the initial slump level of

      200±10 mm. Right after this operation the temperature, air content, and unit weight of the

concrete mixture were measured and then cube specimens were also prepared for 28-day

      compressive strength measurements.

The amount of superplasticizer used for restoring the slump of each concrete

      mixture was determined and in this way the effectiveness of superplasticizer in restoring

the slump of concrete mixture in associated with fly ash and silica fume used was

      underlined.

Based on the measurements obtained at the end of the investigation, it has been

      observed that, depending on the mixing time, the slump losses of concrete mixtures

incorporating fly ash and silica fume were different from concrete mixtures without

      mineral additives and in relation with this the amount of superplasticizer used for restoring

the slump losses of concrete mixtures was also changed.

      Keywords: Workability, Slump loss, Fly ash, Silica fume, Retempering, Superplasticizers