添加爐石或飛灰於混凝土裡已經日益成為趨勢了,不但提高其工作度,也會降低水化熱,並且增加混凝土之晚期強度。因為環保意識的崛起,營造公司盡可能的減低水泥使用量,於是走向同時使用爐石和飛灰取代水泥之配比設計。因此提出能夠準確預測同時添加爐石與飛灰於混凝土之強度模型。 本文主旨是從效率因素k值出發,希望使用爐石和飛灰個別的k值(水泥效能因子)當基礎來預測同時添加爐石和飛灰於混凝土中之強度。本研究之試驗變數包括四種水膠比(0.35、0.45、0.55、0.65),同時使用爐石和飛灰(7:3)來替代水泥0%、30%、40%和50%,再配合收集近年來台灣混凝土中有添加爐石或飛灰之抗壓強度數據來建立一資料庫,並從這些資料和本研究的試驗結果提出兩個預測模型。 結果顯示用爐石和飛灰的個別水泥效能因子來預測同時添加爐石和飛灰於混凝土中之抗壓強度預測是可行的。
Due to the energy consumption of producing cement, the alternative use of industrial byproducts in concrete are beneficial to a country’s economy and reduces environmental pollution. The use of slag or fly ash to replace Portland cement will both yield favorable results such as better workability without water reducing agents, a higher strength at old age and low water hydration heat. The construction industry is now focusing on the ternary use of slag, fly ash and cement as the basis of cement mixture, therefore a prediction model is needed to accurately calculate its compressive strength is of great importance. This study aims to predict the compressive strength of concrete with the ternary use of slag, fly ash and cement, with only the k values of slag and fly ash as the foundation. Four water to binder ratios (w/b) were selected for this experiment (0.35, 0.45, 0.55, 0.65), each ratio having slag plus fly ash replacement levels of 0%, 30%, 40%, 50% respectively, with a 7 to 3 ratio between slag and fly ash. Data is then collected and two models are proposed concerning the ternary blends of slag, fly ash and Portland cement. The results show that it is feasible to superposition the separate k values of slag and fly ash to predict the compressive strength of ternary mixtures.