Yerel bileşenlerle reaktif pudra betonu geliştirilmesi ve alkali-silis reaktivitesinin incelenmesi
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Dosyalar
Tarih
2020
Yazarlar
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Yayıncı
Ege Üniversitesi
Erişim Hakkı
info:eu-repo/semantics/openAccess
Özet
Reaktif pudra betonu (RPB), üstün mekanik, süneklik ve durabilite özelliklerine sahip olan ultra yüksek performanslı bir beton türüdür. RPB, mikroyapıda bütün katı malzemelerin en yüksek yoğunlukta olacak şekilde optimize edilmesi ile yapılır. Bu çalışmada, çeşitli mineral katkılar (silis dumanı, uçucu kül, cam tozu, pomza tozu ve yüksek fırın cürufu) kullanılarak tane boyutu optimizasyon yöntemleri ile RPB üretilmesi, kür koşullarına bağlı olarak basınç dayanımlarının ve hızlandırılmış yöntemle alkali-silis reaktivitesinin (ASR) incelenmesi amaçlanmıştır. Yapılan deneylerde karışım tasarımı Fuller ve Andreasen ile Andersen’in ideal eğrileri kullanılarak hesaplanmıştır. Karışımlar maksimum tane boyutu 2 mm olan kuvars ve bazalt agregalarıyla hazırlanmıştır. Ayrıca çalışmada 28 gün standart su, 1 gün 20°C su+1 gün 60°C sıcak su ve otoklav kürü olacak şekilde 3 tip kür rejimi uygulanmış ve ardından karışımların basınç dayanımları belirlenmiştir. Çalışmanın son aşamasında RPB karışımlarından bazılarının RILEM AAR-4.1 hızlandırılmış beton prizma deneyi ile ASR genleşmeleri periyodik olarak tespit edilmiştir. Bu deneye tabi tutulan bazı numunelerin SEM (Taramalı Elektron Mikroskobu), EDS (Enerji Dağılım Spektrometresi) ve TGA (Termogravimetrik Analiz) analizleri yapılarak içyapılarıyla ilgili bilgiler elde edilmeye çalışılmıştır. En yüksek basınç dayanımları, Andreasen ile Andersen yöntemine göre q=0,20 değerinde hazırlanan, mineral katkı olarak pomza tozu ve yalnızca silis dumanı içeren ve otoklav kürü uygulanan karışımlarda sırasıyla 171 MPa ve 170,5 MPa olarak elde edilmiştir. ASR genleşmeleri bakımından incelendiğinde ise bütün karışımların genleşmeleri RILEM standardının önerdiği sınır değerin altında kalmıştır.
Reactive powder concrete (RPC), is an ultra-high performance concrete type with superior mechanical, ductility and durability properties. RPC is designed by optimizing the gradation of its solid ingredients and obtaining the maximum density by particle packing models. The objective of this study is design and production of RPC by gradation optimization models and incorporating various types of mineral admixtures such as silica fume, fly ash, glass powder, pumice powder and granulated blast furnace slag. The compressive strength of these mixtures after curing by various methods and also alkali-silica reactivity (ASR) were the investigated properties. At the design stage of the study, the ideal particle size distribution curves suggested by Fuller and Andreasen and Andersen were taken as reference. RPC mixtures included quartz and basalt aggregates having maximum aggregate size of 2 mm. Three different curing methods applied in the study included 28-day standard water curing, 1-day 20°C water+1-day 60°C hot water curing and autoclaving. After these curing processes, compressive strength of the mixtures was determined. At the last stage of the study, some of the RPC mixtures were exposed to RILEM AAR-4.1 accelerated concrete prism test and the expansion due to alkali-silica reaction was periodically determined. Some of the specimens exposed to ASR test were analized by SEM (Scannig Electron Microscope), EDS (Energy Dispersive Spectrometry) and TGA (Thermogravimetric Analysis) to detect their microstructural properties. The maximum compressive strength values obtained in the study belong to pumice powder+silica fume (171 MPa) and silica fume (170.5 MPa) incorporating mixtures designed according to Andreasen-Andersen model and having q=0.20 distribution parameter. ASR test results showed that all reactive powder mixtures prepared in the study had lower ultimate expansion than RILEM standart limit.
Reactive powder concrete (RPC), is an ultra-high performance concrete type with superior mechanical, ductility and durability properties. RPC is designed by optimizing the gradation of its solid ingredients and obtaining the maximum density by particle packing models. The objective of this study is design and production of RPC by gradation optimization models and incorporating various types of mineral admixtures such as silica fume, fly ash, glass powder, pumice powder and granulated blast furnace slag. The compressive strength of these mixtures after curing by various methods and also alkali-silica reactivity (ASR) were the investigated properties. At the design stage of the study, the ideal particle size distribution curves suggested by Fuller and Andreasen and Andersen were taken as reference. RPC mixtures included quartz and basalt aggregates having maximum aggregate size of 2 mm. Three different curing methods applied in the study included 28-day standard water curing, 1-day 20°C water+1-day 60°C hot water curing and autoclaving. After these curing processes, compressive strength of the mixtures was determined. At the last stage of the study, some of the RPC mixtures were exposed to RILEM AAR-4.1 accelerated concrete prism test and the expansion due to alkali-silica reaction was periodically determined. Some of the specimens exposed to ASR test were analized by SEM (Scannig Electron Microscope), EDS (Energy Dispersive Spectrometry) and TGA (Thermogravimetric Analysis) to detect their microstructural properties. The maximum compressive strength values obtained in the study belong to pumice powder+silica fume (171 MPa) and silica fume (170.5 MPa) incorporating mixtures designed according to Andreasen-Andersen model and having q=0.20 distribution parameter. ASR test results showed that all reactive powder mixtures prepared in the study had lower ultimate expansion than RILEM standart limit.
Açıklama
Anahtar Kelimeler
Reaktif Pudra Betonu, Mineral Katkı, Basınç Dayanımı, Parçacık Paketleme Modelleri, Alkali-Silis Reaksiyonu, Reactive Powder Concrete, Mineral Admixture, Compressive Strength, Particle-Packing Models, Alkali-Silica Reaction
