矿渣粉对混凝土的性能及耐久性影响试验研究

研究了比表面积为400 m2/kg的矿渣粉,掺量在50%范围内对混凝土的坍落度、强度以及抗渗、抗冻、收缩3方面耐久性的影响。试验研究表明:混凝土中掺入矿渣粉可以降低混凝土的坍落度损失和单位混凝土的用水量;随着矿渣粉掺量的增加,混凝土的早期强度降低,但是矿渣粉掺量在30%以内的混凝土28 d强度要高于基准混凝土;随着矿渣掺量的增加,混凝土的抗渗、抗冻性能增强,收缩值减小。     

含钛高炉重渣的水热固化研究

将含钛高炉重渣与Ca(OH)2以9∶1的质量比混合,添加15%、2 mol/L的NaOH溶液,利用水热固化技术,低温(200℃)制备出抗折强度约15 MPa的建筑材料。结果表明,成型压力、固化温度、固化时间等因素对固化体强度的形成均有重要影响。水热过程中,生成的CSH和水化石榴石晶相是导致固化体强度提高的重要原因。水热固化技术为含钛高炉重渣的大规模综合利用提供了新的途径。     

不锈钢渣和矿渣制备胶凝材料的试验研究

以不锈钢渣和矿渣为主要原料,配加脱硫石膏、粉煤灰、矿物激发剂制备胶凝材料,通过试验确定了原料的最佳质量配比:33％不锈钢渣、35％矿渣、5％脱硫石膏、5％粉煤灰、22％矿物激发剂,利用该配比制备的胶凝材料达到32.5级普通硅酸盐水泥的标准要求.同时,采用XRD分析了胶凝材料的矿相组成,采用扫描电镜对胶凝材料不同龄期水化产物的显微结构进行了分析.     

镍渣矿渣免烧砖的试验研究

研究了镍渣矿渣比和水泥掺量对镍渣矿渣复合胶凝材料体系的影响,并在此基础上,辅以化学激发剂NS、CA,采用正交试验方法,研制开发新型镍渣矿渣基复合胶凝材料,最佳配比为:镍渣和矿渣的质量比5∶5,水泥、激发剂NS和CA分别占镍渣和矿渣总质量的20％、0.5％和2％,胶砂比1∶3,水胶比0.5,可制得符合MU25等级的免烧砖.     

The effect of Persian Gulf tidal zone exposure on durability of mixes containing silica fume and blast furnace slag

In this research the performance of cement paste and concrete mixes incorporating 7% and 10% of silica fume (SF) as a cement replacement was investigated in three exposure conditions. The results showed that plain type II portland cement performed better than blended SF cement under cyclic wetting and drying conditions. Silica fume specimens under cyclic wetting and drying conditions in simulated seawater exhibited higher strength loss compared to plain type II portland cement where cured under potable water. In addition, the greater the silica fume amount used in the mixes, the more the capillary water absorption under tidal zone exposure or/and under wetting and drying simulation. Further, the ternary blended ground granulated blast furnace slag (GGBS) mix was the worst performing mix in all exposure conditions.     

钢渣矿渣复合粉在商品混凝土中的应用研究

本文研究了钢渣矿渣复合粉取代矿渣粉作为商品混凝土掺合料,对混凝土工作性和抗压强度的影响。试验结果表明:采用复合粉取代矿粉对混凝土的工作性和抗压强度无不利的影响,采用复合粉取代矿渣粉作为混凝土掺合料具有良好的经济社会效益。     

矿渣微晶玻璃研制

本文介绍烧结法矿渣微晶玻璃装饰材料的研制。配制原料以矿渣为主,掺入玻璃工业用普通原料以及玻璃析晶时产生矿物所需的成分,经混匀熔化成玻璃后,进行热处理成为均匀微晶结构的玻璃结晶材料。对半工业性试验产品进行了微观结构、外观微孔质量及产品性能分析,并与天然石材的主要性能指标进行了对比。     

粒化高炉矿渣粉在混凝土中的应用

从粒化高炉矿渣粉的基本概念出发,通过对照高价标准,对粒化高炉矿渣粉在混凝土中的作用原理进行了分析,提出了在实际混凝土中应用高炉矿渣粉应该注意的几个问题,以指导实践。     

高炉炉渣在建材工业中的应用

介绍了高炉炉渣在建材工业中的应用。     

水钢高炉重矿渣的应用研究

以贵州省六盘水市水钢高炉重矿渣为试验原料,分析了原料的化学成分、物相组成,并对高炉重矿渣集料的物化力学性能进行了试验研究。以100%高炉重矿渣集料为骨料可获得了C20高炉重矿渣混凝土和M10砂浆,其各项物理力学性能均符合规范要求,这为水钢重矿渣的开发利用提供了理论依据。     

钢渣-矿渣复合微粉的活性试验研究

研究了改变钢渣与矿渣微粉比例以及钢渣微粉比表面积对混合材的机械激发性能,同时考察了自行研制的KYH-8、KYH-9和KYH-10三种激发剂对复合微粉的化学激发,并通过X射线衍射(XRD)、偏光显微(PLM)和电子扫描电镜(SEM)对复合微粉材料进行了结构分析.试验结果表明,复合渣微粉中钢渣的比例越大,钢渣矿渣复合粉的活性越低;钢渣微粉比表面积在400～500m2/kg时,钢渣微粉细度增加,复合微粉活性有所提高;复合微粉在早期只是填充于水泥石之间,起填充剂的作用,后期逐渐水化;0.01 mol/L KYH-10激发剂对钢渣与矿渣微粉比例为3:2的复合微粉激发效果表现最佳,复合微粉7d活性指数达到85%以上,28 d活性指数可以达到104%.     

机械激发对钢渣矿渣微粉活性的影响

将比表面积为400、450、500 m2/kg的钢渣粉进行活性指数试验,并将比表面积为450 m2/kg的钢渣粉与400、450、500 m2/kg三种矿渣粉复合,研究钢渣矿渣复合微粉的活性。试验结果表明:比表面积为500 m2/kg的钢渣粉活性可达一级粉要求。钢渣和矿渣比表面积为450 m2/kg,钢渣掺量在复合微粉为20%~30%时,复合微粉活性可达到或接近S95级,可满足混凝土结构强度设计要求。同时,对复合微粉水化产物微观形貌进SEM观察,以判断复合微粉的水化情况。     

高钛高炉渣在混凝土材料中的应用

高钛高炉渣是攀钢公司炼铁后产生的特有矿渣,由于TiO2含量较高,矿渣的综合利用率低,近年来不断开发高钛矿渣在混凝土中的应用。从高钛矿渣的物理力学性能、高钛渣混凝土的配合比设计和使用性能等方面,对高钛矿渣混凝土的应用进行介绍。实践表明,高钛矿渣混凝土性能优良,综合经济指标好。     

复合激发剂在矿渣-钢渣-粉煤灰三掺混凝土中的应用研究

采用自制的高效复合激发剂,研究了其对矿渣-钢渣-粉煤灰三掺混凝土工作性能和力学性能的影响。结果表明:复合激发剂的使用,对新拌混凝土的工作性能没有不利影响;复合激发剂对设计等级为C30混凝土抗压强度提高的效果明显,而对C50混凝土的作用效果则有所减弱,其原因在于单位体积混凝土中高水泥含量时,水泥对钢渣的水化在早期具有一定的抑制作用。     

双掺粉煤灰和粉状高炉矿渣的自密实混凝土流变性能的研究

研究了以水泥,粉煤灰和粉状高炉矿渣为胶凝材料的自密实混凝土的工作性参数和流变参数,并分析了它们之间的关系。结果表明,掺入10%粉煤灰和矿粉的自密实混凝土的扩展度和T50分别为625 mm和6.4 s,此时混凝土流动性最小。掺入粉煤灰和矿粉均能提高混凝土的扩展度、L仪充填比、屈服应力和塑性黏度,其中粉煤灰对混凝土体系流动性的提高更为显著。随着扩展度的升高,混凝土屈服应力呈下降趋势,而T50与塑性黏度则呈正向的变化关系。     

Residual compressive behaviour of pre-heated high-performance concrete with blast–furnace–slag

An experimental program was designed and carried out to study the residual compressive behaviour of high-performance concrete (HPC) with blast–furnace–slag (BFS) at elevated temperatures ranging from 20 to 800 °C. The residual cube compressive strength is examined and the relationship between the residual compressive strength and temperature is investigated based on the heated cube specimens (100×100×100 mm³) tested on a universal test machine. In addition, on the basis of the heated prism specimens (100×100×300 mm³) tested on an electro-hydromantic rigidity servo test machine, the complete stress–strain curves are obtained, and the effects of temperatures on the residual prism compressive strength, the strain, and the elastic modulus etc are analysed. An approximate formula for the stress–strain relationship of HPC–BFS after exposure to temperatures is proposed.     

Lightweight concretes of activated metakaolin-fly ash binders,with blast furnace slag aggregates

This work investigated geopolymeric lightweight concretes based on binders composed of metakaolin with 0% and 25% fly ash, activated with 15.2% of Na₂O using sodium silicate of modulus SiO₂/Na₂O = 1.2. Concretes of densities of 1200, 900 and 600 kg/m³ were obtained by aeration by adding aluminium powder, in some formulations lightweight aggregate of blast furnace slag was added at a ratio binder:aggregate 1:1; curing was carried out at 20 and 75 °C. The compressive and flexural strength development was monitored for up to 180 days. The strength diminished with the reduction of the density and high temperature curing accelerated strength development. The use of the slag had a positive effect on strength for 1200 kg/m³ concretes; reducing the amount of binder used. The thermal conductivity diminished from 1.65 to 0.47 W/mK for densities from 1800 to 600 kg/m³. The microstructures revealed dense cementitious matrices conformed of reaction products and unreacted metakaolin and fly ash. Energy dispersive spectroscopy and X-ray diffraction showed the formation of amorphous silicoaluminate reaction products.     

磨细矿粉改性及其助磨剂试验研究

通过试验小磨研究了助磨剂石膏、早强剂三乙醇胺对矿渣粉比表面积、粒度分布、活性指数、颗粒形貌等性能的影响。研究表明，石膏3％掺量下对高炉矿渣有明显的助磨效果，矿粉平均粒径下降到4．02μm。最大粒径13．5μm。三乙醇胺在0．8‰掺量下对磨细矿粉有较明显的早期活性增强作用，其机理与其能加速水泥早期水化速率有关。     

环保型无熟料高炉矿渣水泥透水性混凝土的特性

根据目前周内外对透水性混凝土的研究现状,利用无熟料高炉矿渣水泥(简称NSC)配制透水性混凝土,并进行了透水系数、孔隙率、pH、抗压强度等性能测试,结果表明:其抗压强度可达普通混凝土强度等级的C30以上,满足JC/T 446-2000<混凝土路面砖>性能;透水系数≥17.3 mm/s;孔隙率≥27.3%;pH=8.6,有效地解决了透水性混凝土抗压强度低、渗透水强碱化的技术难题.     

Preparation of autoclaved aerated concrete using copper tailings and blast furnace slag

Based on the background that large amount of copper tailings are stockpiled in China, the utilization of skarn-type copper tailings to prepare autoclaved aerated concrete (AAC) was studied. The AAC samples were prepared on a laboratory scale with a dry density of 610.2 kg m⁻³ and compressive strength of 4.0 MPa. Compared with the traditional AAC, lime was totally substituted by skarn-type copper tailings and blast furnace slag in order to develop a potential technique of reducing CO₂ emission during the AAC production process. The samples of different curing stage were examined by XRD, FESEM as well as ²⁹Si and ²⁷Al NMR analyses. Results show that the main minerals in the AAC product are tobermorite-11 Å, anhydrite, augite, quartz, calcite and dolomite, with small amount of other minerals brought in by the copper tailings. It was also suggested that most minerals in the copper tailings participated in the hydration reaction during the procuring process, and the chemical elements in them got into the structure of platy tobermorite in the subsequent autoclaving process.