Mechanical and Permeability Properties of BoronModified-Active-Belite (Bab) Cement Concretes Under Different Curing Regimes

Abstract

The cement manufacturing process requires a high energy consumption. On the other hand, one of the major environmental problems that are faced in this process is the emission of greenhouse gases into the atmosphere. Therefore, the researchers have been investigating the ways to mitigate such problems. Considerable energy savings and reduced CO2 emission are known to be possible during the manufacture of boron modified active belite (BAB) cement. However, the properties of this type of cement have not widely been known, yet In this study, some mechanical and permeability features of BAB cement concretes exposed to distinct onset curing conditions were investigated and compared to that of ordinary Portland cement concretes. Mechanical features were evaluated by compressive and splitting tensile strength developments while the durability features of concretes were measured by means of rapid chloride penetration and water sorptivity tests. Test results showed that BAB cement concretes had almost similar strength properties with the Portland cement concretes. According to
the durability test results, however, BAB cement concretes had superior permeability characteristics when compared to Portland cement concretes

Keywords

• Boron modified active belite cement
• Curing regimes
• Mechanical properties

Boron Modifiye Aktif Belit Çimentolu Betonların Farklı Kür Rejimleri Altında Mekanik ve Geçirimlilik Özellikleri

Abstract

Çimento üretim süreci, yüksek enerji tüketimi gerektirir. Diğer taraftan bu süreçte karşılaşılan büyük çevresel sorunlardan biri de, sera gazlarının atmosfere yayılmasıdır. Bu nedenle, araştırmacılar bu tür sorunları azaltmanın yollarını araştırmaktadırlar. Bor modifiye aktif belit (BAB) çimentosu üretimi sırasında önemli miktarda enerji tasarrufu ve daha az CO2 emisyonu olduğu bilinmektedir. Bununla birlikte, bu tip çimentoların özellikleri henüz büyük ölçüde bilinmemektedir. Bu çalışmada, farklı başlangıç kür koşullarına maruz bırakılan BAB çimentolu betonların bazı mekanik ve geçirgenlik özellikleri araştırılmış ve normal portland çimentolu betonlar ile karşılaştırılmıştır. Mekanik özellikler basınç ve yarma dayanım gelişimleri ile değerlendirilirken, betonların dayanıklılık özellikleri hızlı klorür geçirimliliği ve kılcal su emme testleriyle ölçülmüştür. Test sonuçları, BAB çimentolu betonların mukavemet özelliklerinin normal portland çimentolu betonlarınkilerle neredeyse aynı benzerlikte olduğunu göstermiştir. Ancak dayanıklılık testi sonuçlarına göre, BAB çimentolu betonların normal portland çimentolu betonlarına kıyasla daha yüksek geçirgenlik özelliklerine sahip olduğudur.

Keywords

• Borlu aktif belit çimentosu
• Kür koşullar
• Mekanik özelikler

References

1. [1] Mehta PK (2002) Greening of the concrete industry for sustainable development. Concr International 24: 23– 28.
2. [2] Malhotra VM, Mehta PK (2002) High-Performance, High-Volume Fly Ash Concrete: Materials, Mixture Proportioning, Properties, Construction Practice, and Case Histories, Supplementary Cementing Materials for Sustainable Development, Ottawa, Canada.
3. [3] Sağlık A, Sümer O, Tunç E, Kocabeyler MF, Çelik RS (2008) The Characteristics of Boron Modified Active Belite (BAB) Cement and its Utilization in Mass and Conventional Concrete. 11th International Conference on Durability of Building Materials and Components İstanbul, Turkey.
4. [4] Baysal O (1972) A mineralogical study and genesis of Sarıkaya (Kırka) borate deposits, Hacettepe University, Ankara, Turkey.
5. [5] Helvaci C, Alonso RN (2000) Borate Deposits of Turkey and Argentina; A Summary and Geological Comparison. Turkish Journal of Earth Sciences 9: 1-27.
6. [6] Anthony JW, Bideaux RA, Bladh KW, Nichols MC (2003) Handbook of Mineralogy, Volume V. Borates, Carbonates, Sulfates. Mineral Data Publishing, Tucson, Arizona.
7. [7] Türk S, Gürbüz G, Ertün T, Yeginobali A (2006) Heat of hydration and shrinkage properties of Boron containing active belite cements. ConcreteLife'06 - International RILEM-JCI Seminar on Concrete Durability and Service Life Planning: Curing, Crack Control, Performance in Harsh Environments, RILEM Publications SARL , pp.397 – 404
8. [8] TS 197-1 Cement- Part 1: Compositions and conformity criteria for common cements, Turkish Standards, March 2002.

9. [9] Sui T, Fan L, Wen Z, Wang J, Zhang Z (2004) Study on the properties of high strength concrete using high belite cement. Journal of Advanced Concrete Technology 2: 201-206.
10. [10] Guerrero A, Goni S, Moragues A, Dolado JS (2005) Microstructure and Mechanical Performance of Belite Cements from High Calcium Coal Fly Ash. Journal of American Ceramic Society 88: 1845–1853
11. [11] Poon CS, Kou SC, Lam L (2006) Compressive strength, chloride diffusivity, and pore structure of high performance metakaolin and silica fume concrete. Construction and Building Materials 20: 858–865
12. [12] Güneyisi E, Mermerdaş K (2007) Comparative study on strength, sorptivity, and chloride ingress characteristics of air-cured and water-cured concretes modified with metakaolin. Materials and Structures 40: 1161–1171
13. [13] Güneyisi E, Gesoğlu M, Mermerdaş K (2008) Improving strength, drying shrinkage, and pore structure of concrete using metakaolin. Materials and Structures 41: 937–949.