|Table of Contents|

Effect of Air-bubble Characteristics on Salt Frost Resistance of Concrete(PDF)

《建筑科学与工程学报》[ISSN:1673-2049/CN:61-1442/TU]

Issue:
2011年03期
Page:
83-87
Research Field:
Publishing date:
2011-09-20

Info

Title:
Effect of Air-bubble Characteristics on Salt Frost Resistance of Concrete
Author(s):
ZHANG Yun-qing1; 2;  YU Hong-fa2;  WANG Jia-chun3
1. School of Engineering, Nanjing Agricultural University, Nanjing 210031, Jiangsu, China; 2. Department of Civil Engineering, Nanjing University of Aeronautics and Astronautics, Nanjing 210016, Jiangsu, China; 3. Department of Architectural Engineering
Keywords:
high performance concrete;  air-entrained Portland concrete;  salt frost resistance;  air-bubble characteristic;  freezing-thawing cycle;  relative dynamic elastic modulus
PACS:
TU528
DOI:
-
Abstract:
The salt frost resistance and air void parameters with ordinary Portland concrete(OPC), air-entrained Portland concrete(APC)and high performance concrete(HPC)subjected to the action of 3.5%(in mass fraction)sodium chloride(NaCl)solution were studied by the accelerated freezing-thawing method. The air-bubble characteristic was examined through scanning electron microscopy(SEM). The results show that the diameter is less than 30 μm, the spacing factor is less than 60 μm, and independent distribution of the sealed air-bubble can significantly improve the salt frost resistance of the OPC with water-binder ratio of 0.50; for C40 of the HPC, the air-bubble structure is a major factor for salt frost resistance; adding air entraining agent to obtain excellent air-bubble structure is the effective means for improving salt frost resistance of concrete. Adding silica fume, water-binder ratio is less than 0.31 for HPC, air-bubble structure characteristic is not a major factor for salt frost resistance, this concrete has higher salt frost resistance, even without adding air-entraining agents.

References:

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Memo

Memo:
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Last Update: 2011-09-20