電弧爐還原碴為電弧爐煉鋼之製程下，所產生之副產物，若能將其當作細粒料之使用，不僅能更有效地增加還原碴之使用量，同時減少因堆置過多而造成環境的衝擊，達到雙重效益。 本研究係以水泥搭配爐石粉為主要膠結材，搭配以破碎分選後之爐碴粒料當作粗細粒料，利用兩個不同廠區之還原碴取代部分細粒料（5 %、10 %、15 %），製成控制性低強度回填材料（CLSM），進行CLSM之管流度、坍流度、抗壓強度試驗並探討其膨脹潛能。另一方面，將還原碴各別進行普通、加速安定化處理，依據不同的安定化處理方式，觀察其還原碴之膨脹潛能，評估安定化處理之成效。 試驗結果顯示，建議還原碴以10 %取代部分細粒料應用於CLSM中，其工作性、凝結時間與28天抗壓強度皆能符合國內各施工規範要求，但隨著還原碴取代量增多，會造成凝結時間延長及早期強度發展不足；而CLSM膨脹率皆在0.08 %以下，所以用於回填工程時應不致造成膨脹問題。安定化成效方面，普通安定化處理之齡期需至少90天以上，以確保還原碴內之膨脹因子能有效降低；而加速安定化處理（80℃）在15天以上，可有效抑制還原碴之膨脹。Electric arc furnace reductive slag is the byproduct formed in the electric arc furnace steelmaking process. This study aims at using the slag as fine aggregate in making controlled low strength material (CLSM). This would help increasing utilization of reductive slag, and reducing the amount of stockpiling which is likely to cause environmental concerns. In this study, portland cement and blast furnace slag are used as cementing materials and crushed and sieved slag as coarse and fine aggregates to make CLSM. Reductive slag produced from two different plants are used to replace part of the fine aggregate (5 %, 10 %, 15 %) in proportioning CLSM. Standard test methods for CLSM including pipe flow, slump flow, compressive strength, and swelling potential were conducted to evaluate the effectiveness of using reductive slag in making CLSM. Test results indicated that replacing 10% of the fine aggregate with reductive slag would produce CLSM that meets the consistency, setting time, and 28-day compressive strength specifications for CLSM. Increasing the replacement level of reductive slag tends to increase the setting time and decrease the early strength. An expansion of 0.08% was found for the CLSM made with reductive slag and is judged to be acceptable for backfilling works without causing expansion problems. Also, to ensure that reductive slag does not cause excessive swelling, two stabilization processes were evaluated in this study. These include water-soaking under ambient temperature and at 80°C. It was found that water-soaking at elevated temperature is more effective in stabilizing reductive slag from swelling. In general, it takes 15 days for reductive slag to be stabilized under 80°C water-soaking, while a minimum of 90 days is needed for stabilization of reductive slag at ambient temperature.
