水淬高炉矿渣超细粉的应用与制备

系统介绍炼铁高炉水淬矿渣的性能、矿渣微粉在水泥和混凝土中的应用及矿渣微粉制备的设备和工艺流程，为冶金企业水淬高炉矿渣的深层次开发利用提供重要参考。     

矿物掺合料及硫酸钠对混凝土早期电导率的影响

目的研究混凝土中掺入粉煤灰、矿渣微粉及硫酸钠的电导率变化规律.方法利用电导率仪,测定混凝土从成型开始48h电导率的变化规律.结果硫酸钠的掺入使水泥混凝土电导率峰值滞后;随着粉煤灰、矿渣微粉掺量的增加,混凝土的电导率呈下降趋势;而加入硫酸钠后,粉煤灰电导率随掺量增加而增加,矿渣微粉电导率整体规律并无变化.结论电导率曲线表明了硫酸钠对普通水泥除具有缓凝作用外,还为其早强作用提供了新证据;矿物掺合料的活性低于水泥且矿渣微粉的活性高于粉煤灰,硫酸钠对粉煤灰及矿渣微粉具有较好的激发作用.     

矿渣微粉再生骨料混凝土力学性能试验研究

以矿渣微粉等量取代水泥和使用再生粗骨料等质量取代天然粗骨料2个因素作为变量,利用均匀设计法设计16组试验方案,配制强度等级为C35的再生混凝土,对其抗压强度和工作性能进行试验,研究不同配方下再生骨料混凝土性能的影响规律,找出满足工程技术要求的最佳再生混凝土配合比。研究认为水胶比为0.4,水泥标号为P.O 42.5,矿渣微粉掺量为50%,废混凝土取代率为100%时,再生骨料混凝土实测28 d的强度为40.0 MPa,60 d的强度为42.1 MPa。     

海洋环境下大掺量矿渣微粉混凝土的实验研究

介绍了大掺量矿渣微粉抗海水腐蚀混凝土的3年野外实验结果。通过在海边进行的3年野外实验，证实了大掺量矿渣微粉抗海水腐蚀混凝土的抗氯离子侵蚀能力远较普通混凝土为优，3年浸泡龄期时其中的氯离子渗透深度只有普通混凝土的12％～25％。在大掺量矿渣微粉抗海水腐蚀混凝土中，矿渣微粉的细度宜为420～460m^2／kg；在满足混凝土致密的基础上，胶凝材料用量宜少不宜多。     

水泥矿渣稳定黑土的试验研究

采用水泥、矿渣微粉和石灰进行稳定黑土的试验研究。结果发现，在同等胶凝材料掺量下，采用一定配比的水泥和矿渣微粉，其稳定效果优于普通硅酸盐水泥；采用石灰等量替代部分水泥则导致稳定土的强度下降。虽然水泥矿渣稳定黑土比较经济，但其稳定机理和普通适用性值得进一步深入研究。     

球磨和立式磨矿渣微粉的粒度特性研究

用激光粒度分析仪测定了球磨和立式磨生产的矿渣微粉的颗粒群分布，结果表明，两种产品均符合RRB分布，立式磨矿渣微粉粒度分布范围较窄。水泥粒度分布与Fuller曲线有较大差异，掺入矿渣微粉可使水泥细颗粒部分向Fuller曲线靠近，但粗颗粒部分又进一步远离Fuller曲线。     

高温后纤维矿渣微粉混凝土性能劣化规律

针对纤维矿渣微粉混凝土高温后性能发生劣化的问题,研究了温度、矿渣掺量、钢纤维掺量、聚丙烯纤维掺量和混凝土强度等级对高温后混凝土质量损失以及抗压强度损失的影响.结果表明：纤维矿渣微粉混凝土的外观特征及抗压性能均随受热温度的升高而不断劣化,烧失率和强度损失率均呈现上升趋势;掺入混杂纤维能有效阻止矿渣微粉混凝土发生高温爆裂,保持试件的完整性;矿渣微粉、钢纤维和聚丙烯纤维对混凝土的高温强度劣化均起到了缓解作用,但掺量的变化对质量损失的影响不明显;混凝土强度等级为C60时,纤维矿渣微粉混凝土抗压强度损失降到最低.提出了考虑温度、矿渣微粉掺量和钢纤维掺量影响的纤维矿渣微粉混凝土抗压强度的高温劣化模型.     

用超细矿渣粉及本地原料研制高强高性能混凝土

利用矿渣微粉及粉煤灰的活性,采用本地产PO42.5R水泥和聚羧酸高效减水剂配制C80高性能混凝土,通过正交试验对比研究表明,掺活性指数较高的矿渣粉可以配制C80混凝土,该混凝土具有成本低、取材方便、耐久性好等特点.     

超细矿渣在大流动性,超高强混凝土中的应用研究

研究了超细矿渣掺合料对水泥混凝土性能的影响，结果表明：矿渣经超细粉磨不仅提高了其颗粒细度，且有效提高了其水化活性；超细矿渣作为掺合料掺入水泥中，可提高水泥强度，降低水泥标准稠度需水量；利用超细矿渣掺合料可配制大流动性，超高强混凝土。     

掺矿渣微粉的地面自流平砂浆性能研究

研究了矿渣微粉掺入水泥基自流平地坪砂浆中替代双飞粉后砂浆的各项性能。结果表明,随着矿渣微粉取代双飞粉比例的增加,强度逐渐增强,完全取代时达到最大。同时矿渣微粉的比表面积越大,矿渣的活性发挥越好。而且加入碱性激发剂对矿渣微粉水化活性进行激发,使矿渣微粉的水化活性充分发挥。     

锰渣微粉-石灰石粉作为水泥混合材的试验

以锰渣微粉和石灰石粉按照不同比例进行复掺,研究其物理性能及水化性能。结果表明：锰渣微粉-石灰石粉可以有效减小标准稠度用水量,缩短水泥凝结时间,并且在水泥水化过程中能够很好地发挥其物理、化学综合性能,保证水泥早期和后期的强度。     

矿渣微粉掺量对混凝土力学性能的影响

通过对不同水胶比的矿渣微粉混凝土力学性能进行试验研究,分析了矿渣微粉掺量对混凝土的抗压强度、劈裂抗拉强度、抗折强度以及静力抗压弹性模量的影响.试验结果表明,矿渣微粉掺量对混凝土力学性能影响显著,随着矿渣微粉掺量增加,混凝土7 d强度指标有降低趋势,但90 d强度增长较快,适宜掺量可达30%.     

矿粉对水泥和混凝土性能的影响

为了探寻矿粉细度及掺入量对水泥和混凝土性能的影响,通过试验测试方法,分析了矿粉和水泥的基本性质,研究了超细矿粉和普通矿粉的掺量对水泥基材料标准稠度、凝结时间、流动度和力学性能的影响.结果表明：普通矿粉使水泥净浆标准稠度需水量下降,而超细矿粉则增加标准稠度需水量,两种矿粉都使水泥净浆凝结时间略微延长.普通矿粉可以改善水泥净浆的流动度,超细矿粉的加入则降低了水泥净浆的流动度.普通矿粉和超细矿粉降低水泥净浆早期（7 d）抗压强度,提高后期（28 d）抗压强度,掺10％～50％的普通矿粉的水泥净浆28 d抗压强度提高2.9％～9.7％,掺入超细矿粉28 d抗压强度提高3.9％～20.1％,普通矿粉和超细矿粉的最佳掺量为10％～30％;两种矿粉替代10％～50％水泥所配制的混凝土的强度得到了明显的提高.     

Recycling of industrial waste and performance of steel slag green concrete

Workability and mechanical properties of steel slag green concrete with different types of steel slag and different dosages of admixtures were investigated. The effectiveness of steel slag powder on suppressing alkali aggregate reaction (AAR) expansion was assessed using the method of ASTM C441 and accelerated test method. Experimental results show that mechanical properties can be improved further due to the synergistic effect and mutual activation when compound mineral admixtures with steel slag powder and blast-furnace slag powder are mixed into concrete. In addition, about 50% decrease in expansion rate of mortar bars with mineral admixtures can be achieved in AAR tests. Mineral admixtures with steel slag powder as partial replacement for Portland cement in concrete is an effective means for controlling expansion due to AAR.     

Influence of Thermally Treated Flue Gas Desulfurization （FGD） Gypsum on Performance of the Slag Powder Concrete

The feasibility of flue gas desulphurization （FGD） as concrete admixture was studied. A combined concrete admixture of the thermally-treated FGD gypsum and slag powder was explored. The FGD gypsum was roasted at 200℃ for 60 min and then mixed with the slag powder to form FGD gypsum-slag powder combined admixture in which the SO3 content was 3.5wt%. Cement was partially and equivalently replaced by slag powder alone or FGD gypsum-slag powder, at concentration of 25wt%, 40wt%, and 50wt%, respectively. The setting times, hydration products, total porosity and pore size distributions of the paste were determined. The compressive strength and drying shrinkage of cement mortar and concrete were also tested. The experimental results show that, in the presence of FGD gypsum, the setting times are much slower than those of pastes in the absence of FGD gypsum. The combination of FGD gypsum and slag powder provides synergistic benefits above that of slag powder alone. The addition of FGD gypsum provides benefit by promoting ettringite formation and forms a compact microstructure, increasing the compressive strength and reduces the drying shrinkage of cement mortar and concrete.     

Resource utilization of slag from desulphurization and slag skimming: A comprehensive recycling process of all components

In order to make the slag from desulphurization and slag skimming (SDSS) to be comprehensively recycled and utilized, a combined process of beneficiation and building materials preparation was proposed to recover iron from SDSS, meanwhile to apply the remaining slag tailings as cement admixture. From this process, three iron-rich products were recovered in stages by clean gravity - magnetic separation, slag tailings were left. Slag powder was prepared by ultrafine grinding of slag tailings. The stability, setting time and cement mortar strength of the slag tailings cements (STC) which were mixed with Portland cement and slag powder were studied respectively. The results showed that a proper overall performance still could be obtained at the slag powder content of 30%. Chemical composition analysis, X-ray diffraction (XRD) analysis, metallographic microscope and scanning electron microscope (SEM) analysis were employed to assess the characteristics of the SDSS and the products obtained from the whole process. The results indicated that the three iron-rich products could be used as a raw material for steelmaking and ironmaking and the relatively large amount of calcium silicate (C₂S) and tricalcium silicate (C₃S) in the slag tailings make the addition of slag powder into the Portland cement feasible.     

矿物掺合料对自密实混凝土抗氯离子渗透性的影响

耐久性是自密实混凝土（SCC）的重要性质。本文应用电通量法研究了掺粉煤灰、矿渣的SCC抗氯离子渗透性能,通过对单掺和复掺时SCC电通大小的分析发现：粉煤灰和矿渣都能改善SCC的抗氯离子渗透性能,矿渣提高SCC的抗氯离子渗透性能要优于粉煤灰,二者复掺对SCC抗氯离子渗透的复合叠加效应并不明显。其机理是粉煤灰和矿渣提高水泥石密实性,强化混凝土界面过渡区,粉煤灰、矿渣物理化学吸附作用能固结Cl-,降低Cl-渗透性。SCC中掺入掺合料能减少离析、避免泌水,达到自密实效果,粉煤灰对混凝土流动增大的作用效果要优于磨细矿渣的效果。掺合料复掺对自密实混凝土强度具有复合叠加效应,混凝土28 d强度等级可提高1～2级。     

Effect of glass powder on chloride ion transport and alkali-aggregate reaction expansion of lightweight aggregate concrete

The effects of glass powder on the strength development, chloride permeability and potential alkali-aggregate reaction expansion of lightweight aggregate concrete were investigated. Ground blast furnace slag, coal fly ash and silica fume were used as reference materials. The replacement of cement with 25% glass powder slightly decreases the strengthes at 7 and 28 d, but shows no effect on 90 d’s. Silica fume is very effective in improving both the strength and chloride penetration resistance, while ground glass powder is much more effective than blast furnace slag and fly ash in improving chloride penetration resistance of the concrete. When expanded shale or clay is used as coarse aggregate, the concrete containing glass powder does not exhibit deleterious expansion even if alkali-reactive sand is used as fine aggregate of the concrete.     

Effects of steel slag powder on workability and durability of concrete

The workability and durability of a type of sustainable concrete made with steel slag powder were investigated. The hydrated products of cement paste with ground granulated blast furnace slag（GGBFS） alone or with a combined admixture of GGBFS-steel slag powder were investigated by X-ray diffraction（XRD）. Furthermore, the mechanism of chemically activated steel slag powder was also studied. The experimental results showed that when steel slag powder was added to concrete, the slumps through the same time were lower. The initial and fi nal setting times were slightly retarded. The dry shrinkages were lower, and the abrasion resistance was better. The chemically activated steel slag powder could improve compressive strengths, resistance to chloride permeation and water permeation, as well as carbonization resistance. XRD patterns indicated that the activators enhanced the formation of calcium silicate hydrate（C-S-H） gel and ettringite（AFt）. This research contributes to sustainable disposal of wastes and has the potential to provide several important environmental benefi ts.     

论碱矿渣水泥及混凝土的缓凝问题及缓凝方法

本文分析了缓凝问题对碱矿渣水泥及混凝土应用的影响；讨论了碱矿渣水泥的凝结特点及现有缓凝措施的适用性，认为捅用有效的缓凝剂才是解决该胶凝材料系统易于出现速凝现象的根本途径；有效缓凝剂作用机理及新型复合缓凝剂的研究仍是碱矿渣水泥及混凝土研究领域的重要课题。