SURFACE DAMAGE OF SLAG-CEMENT CONCRETE STRUCTURE EXPOSED TO DEICING-FROST CONDITIONS
The deicing-frost experimentation with test beams made of ordinary Portland cement concrete (OPC), airentrained Portland cement concrete (APC) and high performance concrete (HPC) subjected to the action of 3.5％ (mass fraction) sodium chloride (NaCl) solution was studied by the accelerated freezing method. Adopting to ultrasonic testing method, the surface damaged thickness of concrete structure was detected, and a new evaluation index was put forward, the deicing-frost damaged degree. The results show that the deicing-frost damaged degree of OPC increases sharply and linearly with increase of freeze-thawing cycle. But the addition of air-entrained admixture can efficiently not only decrease deicing-frost damaged degree of the concrete but also enhance its deicing-frost resistance. The deicer-frostingresistance of air-entrained HPC is prodigiously influenced by the amount of mineral admixtures. Airentrained HPC with 50％SG (50％ of binder mass) has strongest deicing-frost resistance, and its typical characteristic is that the deicing-frost damaged degree decreases and in the later period it increases very slowly. Finally, Minimum cover depth of concrete structure exposed to deicing-frost conditions was discussed, and some regulation required by Code for Design of Highway Reinforced Concrete and Prestressed Concrete Bridge and Culverts (JTG D62-2004) was insecure by considered.
high performance concrete air-entrained Portland cement concrete deicing-frost resistance freezing and thawing cycles subsurface damaged thickness
Yun-Qing Zhang Hong-Fa Yu Jia-Chun Wang
Department of Civil Engineering, Nanjing University of Aeronautics and Astronautics, Nanjing 210016, Department of Civil Engineering, Nanjing University of Aeronautics and Astronautics, Nanjing 210016,
国际会议
广州
英文
1100-1105
2009-11-28（万方平台首次上网日期，不代表论文的发表时间）