成型壓力對低水膠比水泥漿體蒸氣養護效能之研究

Abstract

本研究係以具高矽質之波索蘭材料（矽砂及稻殼灰）取代部份水泥，並以不同夯實壓力製作水泥漿試體，於不同催化溫度、恆溫時間及預置期，探討試體的蒸氣養護效能。除了解其抗壓強度發展情形外，並以燒失法、核磁共振分析及掃瞄式電子顯微鏡觀測，印證其水化機理及微觀結構。 研究結果顯示，夯實壓力為25 kgf/cm2時，抗壓強度最好；並在催化溫度180℃、恆溫時間8小時及預置期2小時條件下之抗壓強度最高。此外，以矽砂（即渥汰華標準砂）替代部份水泥之試體，其抗壓強度明顯較RHA-水泥及純水泥者為高。 藉由蒸氣養護方式之試體，其養護一天的抗壓強度，明顯較常溫標準養護二十八天者要高出許多。因此，藉由蒸氣養護方式，除可快速生產製品外，且品質穩定，對營建自動化目標應有相當大的助益。

This study investigates the steam-curing effect on paste cubes prepared by replacing part of cement with high siliceous pozzolanic materials (such as silica sand and RHA) and compacted at different pressure, by varying catalysis temperature, constant-temperature time and presetting time. Besides examining the development of the compressive strength of the paste cubes, study on their hydration mechanism and microstructure are conducted by using ignition loss method, NMR and scrutiny under SEM. It is found by study that the paste cubes manifest best compressive strength at a compaction pressure of 25 kgf/cm2. And the compressive strength peaks for those cubes prepared under the situation of 180°C of catalysis temperature, 8 hours of constant-temperature time and 2 hours of presetting time. In addition, significant improvement in compressive strength is obtained by replacing part of cement with silicon sand (Ottawa standard sand, namely) than RHA-cement or pure cement. The specimens steam-curing for one day also demonstrate compressive strength significantly better than those normally cured for 28 days. Consequently, steam curing proves to be a good method for rapid production of cubes with stable high quality and will be of tremendous value to construction automation.