Effect of Dry Mix Compaction Pressure on Hydration Mechanisms and Strength Growth of Fly Ash Cement

• Main Authors: Chia-Yin Huang, 黃甲寅
• Other Authors: Yaw-Nan Peng
• Format: Others
• Language: zh-TW
• Published: 1995
• Online Access: http://ndltd.ncl.edu.tw/handle/27647269610900276184

碩士 === 國立交通大學 === 土木工程研究所 === 83 === The thesis investigates the compressive strength of hardened paste and mortar specimens mixed with cement and class F Fly Ash ( a product of Hsin-Ta Thermal Power Plant of Taiwan Power Company ) . The specimens are prepared under various dry-mix compaction pressure . These specimens were hardened inside autoclave through different duration and high temperature steam catalytic process.These paste specimens was analyzed with ther- mogravimetry ,nuclear magnetic resonance,and scanning electron microscope to verify its hydration mechanisms and pozzolanic reaction. Based on experimental results , it is concluded that maximum compressive strength was obtained when dry-mix compaction pre- ssure was around 4 kg/cm~^2~z , and catalytic temperature was 180℃.In the early stage of catalysis,more fly ash cement used with lower degree of hydration would result in lower amount of CH and weaker strength . As duration of catalysis increased , both degree of hydration and amount of CH would decrease. However,after 12 hours the amount of CH would decrease, due to pozzolanic reaction compressive strength of the specimens would increase.After 30 hours,the strength of specimens with 40 % fly ash was greater than the strength of specimens without fly ash. Dry-mix pure fly ash specimens showed no strength at all.