水淬轉爐石混凝土可行性之研究

Abstract

將高爐所生產之銑鐵放入轉爐精煉成鋼，並產生轉爐爐渣，經水淬冷 卻稱為水淬轉爐石, 約80％通過#4篩。本研究分兩部份：一•將水淬轉爐 石取代混凝土細骨材。二•將水淬轉爐石粉取代水泥。第一部份在175 、210及280kg/cm2 三種配比設計下，以水淬轉爐石取代細骨材製成混凝 土，但因水淬轉爐石比重大、細粒料少，發生析離現象，所以改為用大部 分水淬轉爐石，及部份飛灰和河砂作為細骨材，來改善並增加其凝聚性且 添加強塑劑增加工作性，結果在水淬轉爐石取代60％、飛灰取代20％細骨 材並添加１％強塑劑混凝土，可得工作性良好，強度高於普通混凝土而透 水和乾縮比普通混凝土稍大一些之飛灰轉爐石混凝土。水淬轉爐石混凝土 經長期曝曬不會產生因熱脹而龜裂之現象。第二部份通過#100篩之水淬轉 爐石粉，取代水泥量，在水灰比0.6與標準砂製成水泥砂漿，結果隨著水 淬轉爐石粉取代水泥量逐漸增加，其抗壓、抗彎、抗拉強度逐漸減低。 During the steel-refining process, the dregs are produced in Basic Oxygen Furance. The dregs quenched by water are called Water Quenched Basic Oxygen Furance (WQBOF) slag. About 80% of WQBOF slag will pass the NO.4 sieve. This research are separt- ed to two part: 1.Using the WQBOF slag to substitute part of the fine aggre- gate of concrete. 2.Using the fine powder of WQBOF slag to substitute cement. In part 1 of this study; there are three kinds of mix design The design strengths of concrete are 175, 210, and 280 kg/cm2. Because WQBOF slag has larger specific gravity and contain le- ss fine power, therefore, WQBOF slag, river sand, and fly ash are used as fine aggregate of concrete to improve its conesio- n. Superplasticizers are also added to improve the workability concrete. When 60% of WQBOF slag and 20% of fly ash are used to substitute fine aggregate, the concrete will get better wo- rkability and higher strength. Moreover, WQBOF slag aggregate concrete will not crack under long-time exposure condition. In the second part of this study; the fine powder of WQBOF slag passed #100 sieve substituted part of the cement of the standard-mortar with a water-cement ratio of 0.6. The specim- en's compressive, flexural, and tensile strength will reduce with increasing WQBOF slag content.