稻殼灰混合水泥的水化和性質

Properties and Hydration of Blended Cements with Rice Husk Ash

本研究探討稻殼灰混合水泥的水化和性質，以 5%、10%及20%的稻殼灰重量比取代水泥。針對凝結時間、工作性、卜作嵐活性指數、熱壓膨脹、抗壓強度和抗彎強度進行測試。透過X 光射線分析觀察水化產物的結構，採用掃描式電子顯微鏡分析硬固水泥漿的微觀結構。結果顯示混合稻殼灰，灰份含量的增加，降低了水泥用量，水化過程減慢，導致增加凝結時間。卜作嵐反應造成氫氧化鈣的減少和水化產物C-S-H 膠體的增多，致使微結構更加緻密，強度增大。

This research investigates the properties and hydration of blendedcements with rice husk ash. A reference sample and three cementsreplacement 5%, 10% and 20% weight % rice husk ash were tested.Setting time, flowability, pozzolan activity index, autoclave expansion,compressive strength and flexural strength were measured. The hydratedproducts were identified by X-ray diffraction. The microstructure of thehardened cement paste and their morphological characteristics wereexamined by scanning electron microscopy. It is concluded that theincrease of rice husk ash content reduces the cement content in the mix,and the hydration process slows down causing setting time to increase.The calcium hydroxide decreases and the hydration product C-S-H gelincreases as a result of the pozzolanic reaction, the microstructure becomesdenser and the strength is increased.