蒸氣催化濕拌水泥砂漿試體強度發展與蒸氣催化模式之關係研究

Abstract

本研究係以矽砂〔渥太華標準砂〕取代部分的水泥製成水泥砂漿試體，藉由矽砂的高矽質與水泥中的鈣於高溫蒸氣催化的養護條件下，發生熱反應，產生高強度的托勃莫萊石（tobermorite）水化生成物。 本試驗以高溫、高壓蒸氣催化濕拌水泥砂漿試體，主要變數有：矽砂取代水泥量、溫度〔壓力〕、催化齡期、預置期。並藉SEM與燒失法求得水化程度、CH含量及硬固後試體的抗壓強度，以了解其水化機理與強度發展。 由於高溫、高壓蒸氣催化卜特蘭混凝土具有早強與結構緻密性的優點，如在此催化條件下若存在有額外的氧化矽，將改良原有之水化產物，而提高強度與耐久性。而水泥砂漿內所添加的矽砂恰可提供為氧化矽的來源，因此以高溫高壓蒸氣催化水泥砂漿，對5cm立方試體而言，最佳壓蒸溫度、時間與預置期分別為180℃、12小時與2小時，其水泥砂漿抗壓強度可達1635kg/cm2以上。

The proposed method is to replase some part of cement in the specimens with silica(Ottawa sand), By dint of the CaO and SiO2 of cement and silica being heat-reaction through high temperature steam-injection process, and that produced high-strength tobermorite. The testing variable includes: the percentage of silica, temperature(pressure), hydration duration and preset. Meanwhile, We gain the hydration degress and cement of Ca(OH)2 through the SEM and method of loss of ignition and compressive strength after hardening to understand hydration Mechanisms and strength growth. Because the Potland Concrete under high-temperature and high-pressure steam has the advantage of early-stage strength and dense-structure; and if there exists extra SiO2 under this catalysis condition, the original hydration produce will be improved, and its strength and durability will be higher. The silica added in cementsand paste just can serve as the source of SiO2, Hence, cement-sand paste through high-temperature and high-pressure steam-injection process. All cement-sand paste cubes(5cm) made by exposing wet mixes to 180℃ steams for 12 hours hydration duration and 2 hours preset developed strength greater than 1635kg/cm2.