Paper Title:
Experiment and Micro-Mechanism Study on Mechanical Properties and Durability of High-Calcium Fly Ash Concrete
  Abstract

Low-calcium fly ash is paid much attention for its wide use in engineering, the research and application technology of it are very mature, but as to high-calcium fly ash concrete, the researches on stability, mechanical property and durability of it are very less , The existing researches are still inadequate for practice of engineering. As to this problem, using small shek kip hydropower project as example, the volume stability of high-calcium fly ash concretes with different fly ash dosages are tested, then the optimal dosage of the high-calcium fly ash is determined; based on this, the impacts of high-calcium fly ash on the performance of mechanical properties , impermeability and frost resistance of concrete are studied; Finally, macro performance is analyzed from a micro-mechanism point of view through taking the electron micrograph. As the study shows, the optimal dosage of high-calcium fly ash should be taken as 20% -25%; for the concrete with special requirements, the dosage can be relaxed to 30% when the high-calcium fly ash achieves high quality. The compressive strength of high-calcium fly ash concrete is higher than the low-calcium fly ash concrete. Strength development advantage of high-calcium fly ash concrete reflects at the early age, this advantage takes the trend of weakening as the development of age. Concrete mixed with high-calcium fly ash has good performance in impermeability. The high-calcium fly ash has high activity, the high-calcium fly ash and secondary hydration reaction products can be filled into the pore capillary and cracks of the concrete structure, improving the pore structure, thereby increasing the density of cement paste. High-calcium fly ash concrete has good performance in frost resistance. The destructive effects of freeze-thaw cycles on cement structure has connection with the microstructure of cement and impermeability , the improvement of impermeability avoids the water entering into the concrete, reduces the risk of destruction caused by frost heave.The study on micro-mechanism proves well the macro-phenomena above.

  Info
Periodical
Key Engineering Materials (Volumes 480-481)
Edited by
Yanwen Wu
Pages
59-65
DOI
10.4028/www.scientific.net/KEM.480-481.59
Citation
S. X. Li, T. S. Yang, Z. M. Wang, Q. Hu, "Experiment and Micro-Mechanism Study on Mechanical Properties and Durability of High-Calcium Fly Ash Concrete", Key Engineering Materials, Vols. 480-481, pp. 59-65, 2011
Online since
June 2011
Export
Price
$32.00
Share

In order to see related information, you need to Login.

In order to see related information, you need to Login.

Authors: Zhi Min He, Jun Zhe Liu, Tian Hong Wang
Abstract:In precast concrete elements manufacturing, steam-cured concrete incorprating 30% mineral admixtures encountered the problem of too low...
1535
Authors: Jian Hua Wu, Yun Lan Liu
Abstract:This paper studies the influence of different mineral admixtures(fly ash and ground granulated blast furnace slag)on the carbonation...
366
Authors: Ying Jun Mei, Jin Hang Wu, Jian Hua Zheng
Chapter 4: Ecological Architecture and Building Energy Saving Technology
Abstract:The reutilization of waste concrete and fly ash produced by power plant is one way to develop green concrete. The addition of fly ash in...
654
Authors: Xue Song Zhang
Chapter 7: Building Materials
Abstract:Based on the mechanism of concrete carbonation, the effects of content of fly ash in the binder, the water to binder ratios, compound...
1688