矿渣钢渣复合胶凝特性及其用于海工混凝土的试验研究

发布时间：2018-06-06 03:14

本文选题：矿渣钢渣复合 + 胶凝性能　；参考：《暨南大学》2014年硕士论文

【摘要】：与矿渣相比，作为冶金渣之一的钢渣，由于其存在早期活性及安定性等问题，致使其在水泥混凝土行业的利用价值并不高，导致冶金渣的综合附加值未能达到最大化。为了进一步加大冶金渣的综合利用率，本文将矿渣钢渣磨细后进行复合，针对矿渣钢渣复合胶凝特性及其用于海工环境进行了试验研究，主要内容如下：（1）矿渣、钢渣基本性质的研究。结果表明：钢渣化学组成与水泥较为相似，拥有潜在的胶凝活性，另通过碱度计算，可以判断试验用钢渣为高钙渣，从化学组成来看，试验用矿渣为酸性渣，质量系数为2.03，有较高的活性基础；在粉磨性能方面，钢渣较矿渣易磨，但钢渣难磨相较矿渣多，且二者磨细粉的过筛（0.08mm）微粒径范围要优于水泥，具备掺合料的物理填充基础。（2）矿渣粉、钢渣粉单掺及复掺对胶砂性能的研究。结果表明：单掺掺量25%时，矿渣粉和钢渣粉比表面积分别在430m2/kg、584m2/kg左右，其在能耗和活性方面能达到了较好地结合；在单掺掺量方面，矿渣粉在70%掺量时亦能保证其后期活性，而钢渣粉最大掺量不宜超过20%；在复掺方面，若参考一级钢渣粉的行业标准，，矿渣钢渣复合微粉总掺量分别为40%和50%时，其中钢渣粉所占比例不宜超过60%和50%；利用三种激发剂进行激发效能对比，其在7d和28d表现出了正负激发效果，表现为无水硫酸钙激发效果和稳定性最好，氢氧化钙次之，硅铝酸钠不宜单独作为激发剂。此外，矿渣粉、钢渣粉的单掺及复掺均能保证胶砂具有较优的流动性。（3）矿渣粉、钢渣粉单掺及复掺对水泥水化产物组成及微结构的研究。结果表明：单掺及复掺入水泥的水化产物组成成分大致相同；相比矿渣粉，钢渣粉在水化达到后期时才逐渐展露其活性；净水泥浆石的微裂纹较多，而掺入50%复合微粉的水泥浆石在微裂纹较净水泥浆石明显要少，其微孔洞较单掺矿渣粉要较略少，说明了二者的复合在微观上具备一定的协调效应。2.5%的无水硫酸钙掺入，可以减少复合微粉-水泥浆石的微孔洞。（4）矿渣粉、钢渣粉、粉煤灰相互复合掺入对混凝土力学及工作性能的研究。结果表明：微粉复合后掺入混凝土对其工作性能总体有利；在强度方面，矿渣粉与钢渣粉复合要优于矿渣粉与粉煤灰复合，在28d活性基本与单掺矿渣粉无异。高活性品种矿渣粉对矿渣钢渣复合微粉早期活性影响较大，后期基本无异；矿渣粉与钢渣粉在高水胶比下复合活性协调效应较低水胶比更易发挥；单掺无水硫酸钙作为矿渣钢渣复合微粉的激发剂以2%掺量为宜，无水硫酸钙和氢氧化钙作为复合激发剂时，未能发挥复合激发效果。（5）矿渣粉、钢渣粉、粉煤灰相互复合掺入混凝土在海工环境耐久性的研究。微粉在各总掺量及各复合比例下掺入混凝土，通过其耐海工环境的5项试验结果表明：其掺入可以改善在混凝土抗氯离子渗透性能方面，提高幅度在10%~43%之间，矿渣粉与钢渣粉复合优于矿渣粉与粉煤灰复合，且均优于单掺矿渣粉的改善效果；其掺入可以改善混凝土抗硫酸盐腐蚀性能，最高提升幅度达到20%，矿渣粉和钢渣粉或粉煤灰的复合均能优于单掺矿渣粉对混凝土抗硫酸盐性能的改善，复合微粉总掺量以40%为宜；其掺入可以改善混凝土抗人工海水腐蚀性能，最大提升幅度达到12%，在总掺量为30%时，矿渣粉与粉煤灰的复合较矿渣粉与钢渣粉复合要好，但随着总掺量增加至50%时，矿渣粉与钢渣粉的复合效果基本与矿渣粉与粉煤灰的复合等效，但均优于单掺矿渣粉的改善效果；其掺入可以改善混凝土早期开裂性能，总掺量为50%时，以矿渣粉和钢渣粉复合效果最优，矿渣粉与粉煤灰复合次之，单掺矿渣粉最弱；对于混凝土耐磨性能方面，矿渣粉的掺入不利于混凝土耐磨，而其与钢渣粉或粉煤灰复合后可以改善此“危害”，但只有复合微粉总量达到50%时，才优于未掺微粉的水泥混凝土。本文的研究为利用矿渣、钢渣制备复合微粉掺合料用于水泥混凝土行业的研究及推广提供基础，为矿渣钢渣复合微粉相关应用技术规范提供参考。
[Abstract]:Compared with slag, steel slag, as one of the metallurgical slag, has a low utilization value in the cement concrete industry because of its early activity and stability, which leads to the failure to maximize the comprehensive added value of the metallurgical slag. In order to further increase the comprehensive utilization ratio of metallurgical slag, the slag steel slag has been grinded in this paper. In view of the composite cementitious characteristics of slag steel slag and its application in marine environment, the main contents are as follows:
(1) research on the basic properties of slag and steel slag. The results show that the chemical composition of steel slag is similar to cement and has potential cementitious activity. By the calculation of alkalinity, it can be used to judge the test steel slag as high calcium slag. From the chemical composition, the slag is used as acid residue, the mass coefficient is 2.03, and has a higher activity base; in the grinding performance square. On the other hand, steel slag is easier to wear than slag, but steel slag is more difficult to wear than slag, and the size range of the two grinding powder is better than the cement and has the physical filling foundation of the admixture.
(2) study on the properties of slag powder, steel slag powder single addition and compound admixture. The results show that the specific surface area of slag powder and slag powder is about 430m2/kg and 584m2/kg, respectively, when the amount of single admixture is 25%, and its energy consumption and activity can be better combined, and the slag powder can also ensure its later activity in the addition of the dosage of 70%. The maximum dosage of slag powder should not exceed 20%. In the case of the industry standard of the first grade slag powder, the proportion of slag and slag powder is 40% and 50% respectively, and the proportion of slag powder should not exceed 60% and 50%, and the effect of positive and negative excitation on 7d and 28d shows the effect of positive and negative excitation by using three kinds of activator. The effect and stability of the anhydrous calcium sulfate are the best, the calcium hydroxide is the second, the sodium aluminosilicate should not be used alone as a activator. In addition, the slag powder, the single mixing and mixing of the slag powder can guarantee the better fluidity of the mortar.
(3) the study on the composition and microstructure of the hydration products of cement with slag powder, steel slag powder and compound admixture. The results show that the composition of the hydrated products is roughly the same, and the slag powder gradually shows its activity when the hydration reaches the later stage, and the micro crack of the net cement paste is more than that of the slag powder, and the 50% composite microcracks are mixed with the slag powder. The pulverized cement paste is less than the net cement paste, and the micropore cavity is less than the single slag powder. It shows that the composite calcium sulfate, which has a certain coordination effect of.2.5%, can reduce the micropore of the composite micropowder cement paste.
(4) the study of slag powder, slag powder and fly ash mixed with each other on the mechanical properties and working properties of concrete. The results show that the combination of micro powder and concrete is generally favorable to its working performance. In strength, the combination of slag powder and slag powder is better than that of slag powder and fly ash, and the activity of 28d is basically higher than that of single slag powder. The active variety slag powder has great influence on the early activity of the slag steel slag compound powder, and the later is basically the same. The slag powder and steel slag powder are more easy to play with the lower water gel ratio under the high water glue ratio. The 2% content of the activator with single calcium sulfate as the slag steel slag compound powder is suitable, the anhydrous calcium sulfate and the calcium hydroxide As a composite activator, the compound excitation effect can not be realized.
(5) research on the durability of slag powder, steel slag powder and fly ash mixed with concrete in the marine environment. Micro powder is mixed with concrete under the total content and the ratio of each compound. Through the 5 test results of its marine environment, it can improve the permeability of concrete to the chloride resistance, and increase the range between 10%~43% and mine. The combination of slag powder and slag powder is better than slag powder and fly ash, and it is better than single slag powder. The addition of slag powder can improve the sulfate corrosion resistance of concrete, the maximum lifting range is 20%. The compound of slag powder and slag powder or fly ash can be better than that of single slag powder to improve the sulfate resistance of concrete. The total addition of micro powder is 40%, which can improve the corrosion resistance of concrete to artificial seawater, the maximum lifting range is 12%. When the total content is 30%, the compound of slag powder and fly ash is better than slag powder and slag powder. But with the increase of total content to 50%, the compound effect of slag powder and slag powder is basically with slag powder and slag powder. The compound equivalent of fly ash is better than the improvement effect of single slag powder; its addition can improve the early cracking performance of concrete. When the total content is 50%, the combination of slag powder and slag powder is the best, the slag powder is mixed with the fly ash, and the single slag powder is the weakest; for the wear resistance of concrete, the admixing of slag powder is unfavorable. Concrete is wear-resistant, and it can be improved with steel slag powder or fly ash, but only when the total amount of composite powder reaches 50%, it is better than the cement concrete without fine powder.
The research in this paper provides a basis for the research and promotion of cement concrete industry by making use of slag and steel slag to prepare compound micro powder admixture for cement concrete industry. It provides reference for the related application technical specifications of slag steel slag composite micro powder.
【学位授予单位】：暨南大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TV431

【参考文献】