Study of the properties of Interfacial Transition Zone and the Durability of Concrete

• Main Authors: Kuo-Yu Liao, 廖國裕
• Other Authors: Yaw-Nan Peng
• Format: Others
• Language: zh-TW
• Published: 2004
• Online Access: http://ndltd.ncl.edu.tw/handle/64jjcn

博士 === 國立交通大學 === 土木工程系所 === 92 === Abstract This research is to investigate the Interfacial Transition Zone (ITZ) of Wet Mixed high performance concrete curing in lime water or sodium sulfate solution to get accelerate inferior test. From SEM(Scanning Electron Microscope), Wet Mixed concrete curing in lime water, it was found that the pores and hydration products at the Interfacial Transition Zone within 100μm between paste and aggregate were permuted each other during the early hydration stage and then appeared as large lump or strip. They gradually became irregular and small lump for the further curing age. At the 56 days curing age, pores almost concentrated within an area of 0-15μm from the aggregate edge. The hydration products were much denser with the increase of its distance from aggregate edge. Further, to compare the situation of curing in sodium sulfate solution, we find the hydration products AFm appeared in the sample at 7 days age curing in lime water, but it appeared at 14 days age in the sample curing in sodium sulfate. The pore shape of 14 days curing in lime water, appeared a mesh distribution, but the same pore shape was appeared at 28 days age curing in sodium sulfate. From SEM of accelerate inferior test at 14 days, the C-S-H products after 15 times accelerate inferior test that existed more pores. From the result of interaction test, we found that aggregate and paste not appeared interaction, so that, the bond strength of aggregate and paste was control by hydration products only. We find the hydration products AFm was appeared on aggregate edge and amount of CH was not enough let fly-ash to progress Pozzolanic reaction. Although, add Pozzolanic material can not to improve the bond strength of interface, but Pozzolanic reaction can improve compressive strength of ITZ, so that, the full strength of HPC was larger than traditional concrete.