Mechanism and Properties of Cementitious Composites using CFBC Fly Ash

• Main Authors: Hui-Chi Huang, 黃暉淇
• Other Authors: Ran Huang
• Format: Others
• Language: zh-TW
• Published: 2008
• Online Access: http://ndltd.ncl.edu.tw/handle/44683993044817712208

碩士 === 國立臺灣海洋大學 === 材料工程研究所 === 96 === In recent years, sustainable development policy has been established in many countries and it has been prevailing to reuse or recycle the industry by-products or non-tixic wastes all over the world. In construction sector, industry by-products such as coal-fired fly ash, silica fume and ground granulated blast furnace slag has been used as cement replacement materials (CRM) or supplementary cementing materials (SCM) for many years and lots of research results have been published in many journals and can be easily acquired. However, the technology information of relatively new by-product - circulating fluidized bed combustion ash (CFBC ash) is scarce and more researches are needed to investigate the mechanism and feasible application of CFBC ash. Test results indicate (1)CFBC fly ash has angular shape and rough surface; (2) CFBC fly ash does not fullfils the requirements of ASTM C618 (pozzolanic material chemical properties requirements) and ASTM C311 (strength activated index); (3) CFBC fly ash would harden in the air; (4) CFBC fly ash used as filler in the cementitious composites would reduce water absorption, increase compressive strength and improve sulphate resistance, but large amount replacement may influence workability; (5) CFBC fly ash application would change the amount of ettringites and C-S-H gel crystallization; it was also found that the non-reacted gypsum would appears as prismatic crystal in the composites; (6) mix proportions with proper amount CFBC ash would satisfy the requirements of specified CLSM.