【摘要】：高效減水劑和優(yōu)質(zhì)活性礦物摻合料的摻入,促使混凝土可以在較低水膠比的條件下形成高強度混凝土。而我國優(yōu)質(zhì)摻合料資源有限,已經(jīng)突顯出短缺現(xiàn)象,開發(fā)新的摻合料迫在眉睫。煤矸石富含硅、鋁質(zhì)成分,經(jīng)過一定的活化處理后具有一定的活性和微骨料效應,使其制備優(yōu)質(zhì)礦物摻合料成為可能。目前對于煤矸石作為礦物摻合料的研究尚不成熟,尤其是對未燃煤矸石的研究更為少見。本文是國家自然科學基金委員會與神華集團有限公司聯(lián)合資助項目—“煤矸石在水泥和混凝土中資源化利用關(guān)鍵科學問題研究”(U1261122)中的子項目,所有研究成果都是在該基金的資助下完成并取得的,主要研究成果如下：(1)膠砂強度評價表明：粒徑≤2.5mm的未燃煤矸石顆粒經(jīng)過煅燒研磨處理后,按30%取代42.5水泥制備的煅燒煤矸石粉-水泥膠砂強度達到42.91MPa,活性指數(shù)高達0.89,優(yōu)于I級粉煤灰,稍遜于S95礦粉；(2)不同品種礦物摻合料復摻的正交試驗表明：粉煤灰對于混凝土拌合物工作性改善程度最大；煤矸石摻合料與硅灰復摻時,在有聚羧酸系減水劑配合使用的條件下,同樣可以配制出流動性與粉煤灰-硅灰復摻相近的效果；不同種類礦物摻合料對高強混凝土強度的貢獻程度為：煅燒煤矸石粉自燃煤矸石粉I級粉煤灰,幾種摻合料均對混凝土長期強度有不同程度的提高,其中煅燒煤矸石粉與硅灰復摻對混凝土長期強度的提高貢獻最大；(3)C70煅燒煤矸石粉摻合料的單因素對比試驗表明：煅燒煤矸石粉摻量對于混凝土拌合物初始坍落度影響較小,拌合物經(jīng)時損失隨摻量增加有遞增趨勢；煅燒煤矸石粉摻量為10%時混凝土7d強度最高,隨著摻量的增大強度有所降低；混凝土28d強度隨摻量的遞增表現(xiàn)為先升高后降低的趨勢,摻量在20%時強度最高；煅燒煤矸石粉摻量在20%以內(nèi)時,對混凝土56d強度仍有提高作用；煅燒煤矸石粉的摻入能夠顯著提高混凝土的抗氯離子滲透性能,摻入量在30%以內(nèi)時,混凝土28d、56d電通量隨摻入量遞增大幅度下降：煤矸石礦物摻合料混凝土具有極佳抗凍融能力,煅燒煤矸石粉的摻入,能夠提高混凝土抗凍融性,經(jīng)過1500次凍融循環(huán),混凝土表面仍無明顯剝蝕脫落現(xiàn)象,質(zhì)量和動彈性模量損失率都滿足規(guī)范要求。研究結(jié)果表明,單摻煅燒煤矸石粉配制高強混凝土可行。
[Abstract]:The addition of high efficiency water reducing agent and high quality active mineral admixture can promote the formation of high strength concrete under the condition of low water / binder ratio. But our country high quality admixture resource is limited, already highlighted the shortage phenomenon, the development new admixture is imminent. Coal gangue is rich in silicon and aluminum. After certain activation treatment, it has certain activity and microaggregate effect, which makes it possible to prepare high quality mineral admixture. At present, the study of coal gangue as mineral admixture is still immature, especially for unburned coal gangue. This paper is a sub-project of the National Natural Science Foundation Committee of China and Shenhua Group Co., Ltd., which is a joint project of "study on key Scientific problems of Utilization of Coal gangue in cement and concrete" (U1261122). All the research results were completed and obtained with the aid of the fund. The main research results are as follows: (1) the evaluation of the strength of cement sand shows that the unburned coal gangue particles with diameter 鈮，

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