钢渣全组分梯级利用研究

提出了一种钢渣全组分梯级利用的方式,研究发现利用4.75mm以上的钢渣作粗集料制备AC-13沥青混凝土,其各项性能与普通玄武岩AC-13基本相同;利用4.75mm以下钢渣作细集料制备砂浆,当采用20%~40%的钢渣等体积取代石灰岩机制砂时,砂浆的性能与普通机制砂砂浆基本一致;将磨细钢渣粉用作水混合材时,单掺10%~20%的钢渣粉所制备的水泥和采用30%的钢渣粉与20%的矿渣微粉所制备的水泥都能达到P·O 42.5水泥的标准。     

钢渣全组分梯级利用研究

提出了一种钢渣全组分梯级利用的方式,研究发现利用4.75mm以上的钢渣作粗集料制备AC-13沥青混凝土,其各项性能与普通玄武岩AC-13基本相同;利用4.75mm以下钢渣作细集料制备砂浆,当采用20%~40%的钢渣等体积取代石灰岩机制砂时,砂浆的性能与普通机制砂砂浆基本一致;将磨细钢渣粉用作水混合材时,单掺10%~20%的钢渣粉所制备的水泥和采用30%的钢渣粉与20%的矿渣微粉所制备的水泥都能达到P·O 42.5水泥的标准。     

多晶硅滤液废渣用于水泥混合材及熟料制备的研究

利用荧光光谱法分析多晶硅废渣的化学组分,将其与其他原料进行配比,制备水泥熟料,并检测所得样品的物理化学性能。同时检测多晶硅废渣用作水泥混合材的水化活性指数、氯离子等关键项目。结果表明,多晶硅废渣可作为熟料制备的硅质补充原料,但用作水泥混合材的水化活性不足,且氯离子含量较高。     

改性氯氧镁发泡水泥的制备与性能研究

利用矿物掺合料和化学外加剂对氯氧镁水泥改性,并利用改性的氯氧镁水泥制备发泡水泥,研究改性组分对氯氧镁发泡水泥性能的影响。结果表明,矿物掺合料与化学外加剂复掺可提高氯氧镁水泥的耐水性,软化系数高于单掺时的软化系数;加入改性组分后,发泡水泥的密度增大1%左右,抗压强度降低约3%;改性组分对发泡水泥的导热系数影响不大;加入改性组分后,氯氧镁水泥发泡水泥的耐水性提高50%。     

复合保温砌块用无机芯材的制备研究

发泡剂种类对泡沫混凝土浇筑稳定性具有重要影响。通过掺入缓凝组分(PHA)解决了磷石膏粉作胶凝材料在制备浆体时出现的结粒、分散不均匀问题,制备的石膏基泡沫混凝土干密度为275kg/m3,28d抗压强度0.17MPa,导热系数为0.0620W/(m.K),符合设计要求。采用纯P.O42.5水泥做胶凝材料时浆体出现塌模,通过掺入5%的早强组分(ZQ)和15%II级粉煤灰取代水泥,0.5%早强型FDN减水剂,制备的水泥基泡沫混凝土干密度为245kg/m3,28d抗压强度0.18MPa,导热系数为0.0645W/(m.K),符合设计要求。     

提高预分解窑水泥 ISO 强度的应对措施

水泥ISO强度检验方法的实施,对我国水泥工业的技术进步和提高水泥实物质量具有十分重要的意义,本文结合云南红塔滇西水泥股份有限公司的生产实际,对影响预分解窑水泥ISO强度的各种因素进行了一系列的试验研究,通过研究发现,影响水泥ISO强度主要有熟料工艺质量、煅烧工艺装备、水泥制备等环节。在这些环节中,熟料率值及矿物组成、熟料的R2O、f-CaO、SO3微量组分,煅烧温度,以及水泥制备中的细度、比表面积、颗粒级配、混合材、石膏等对水泥ISO强度都有影响,因此这是一个系统的优化的课题。针对这些因素,采取一系列的应对措施,对预分解…     

水泥中磷矿渣掺量的测定

我省磷矿资源相当丰富,随着对磷矿资源的开发利用,每年将排放电炉磷渣数拾万吨.粒化磷渣做水泥混合材,其经济效益远优于火山灰和粉煤灰;掺10—15%磷渣做水泥混合材,其经济效益和高炉矿渣基本相同.为了在生产中控制磷矿渣的掺量,我们选用了氟离子电极法.本方法是基于我省磷矿渣中的特殊组分氟含量约2—3%,而水泥中的其它组分,如天然石膏和熟料等基本不含氟,因此水泥中氟含量的多少可以完全由磷矿渣掺入的多     

一种革屑水泥发泡剂的制备方法

介绍了一种动物蛋白基水泥发泡剂的制备方法,主要以含铬革屑为原料,将其水解脱铬后,离心抽滤,将所得水解液与其他稳泡组分和增强组分进行复配,均匀混合并制得动物蛋白基水泥发泡剂。所得发泡剂发泡能力强、泡沫细腻均匀、稳定性高、价格便宜,原料易得,并拓宽了制革固废资源化利用途径,可较好地解决制革行业固废回收利用问题。     

混凝土抗侵蚀防腐剂性能研究

采用工业废渣、活性激发组分及阻锈组分制备混凝土抗侵蚀防腐剂,以中、高抗硫酸盐水泥为对比样,研究了混凝土抗侵蚀防腐剂的化学组成、力学性能与耐蚀性能。结果表明,混凝土抗侵蚀防腐剂的抗蚀性能介于中、高抗硫酸盐水泥之间,可以显著提高混凝土的密实性与抗侵入性,具有良好的抗盐类侵蚀功能。氯离子含量仅为0.03%,28d抗压强度比104%,28d膨胀率0.38%,抗蚀系数1.12,膨胀系数1.10,氯离子扩散系数比0.56。     

生产复合水泥的粉磨工艺和质量问题——匈牙利L.Opoczky

本文研究了由熟料与矿渣、粉煤灰、凝灰岩和石灰石中的任两种混合材组成的复合水泥的粉(?)工艺和质量特性。由三种组分组成的复合水泥的易磨性好于熟料的易磨性,其搅拌需水量和和易性取决于其颗粒级配,两复合水泥的颗粒级配又受到混合材的种类和易磨性的影响。易磨性好的组分会导致颗粒级配变得较宽,且通常其搅拌需水量较小。粉煤灰和石灰石比凝灰岩更能使颗粒级配变宽。含火山灰质组分的复合水泥的搅拌需水量是较大的。尤其当含有凝灰岩时更是如此。为了达到标准强度,复合水泥须比(?)含混合材的水泥磨得更细。由熟料、矿渣和石灰石组成的复合水泥除了具有易磨性好的工艺特性外,还具有最好的稠度和高抗压强度。     

水泥粒径分布对混凝土抗压强度影响的试验研究

为了考察水泥粒径分布对混凝土抗压强度的影响,开展了试验研究。首先,将普通硅酸盐水泥经气流粉碎机生产获得化学组分相同、粒径分布不同的超细水泥,然后通过掺加超细水泥改变水泥粒径分布。分别测定了3种不同超细水泥掺量下的水泥等温放热曲线和混凝土抗压强度。试验结果表明:①掺加适量超细水泥能够优化水泥粒径分布,提高水泥利用率,增加混凝土抗压强度;②混凝土抗压强度并不一定随超细水泥掺量的增加而递增,存在一个最佳的超细水泥掺量,使水泥粒径分布最优,从而获得最高的混凝土抗压强度。     

粉煤灰水泥堆积效应与其抗压强度的关系

将粉煤灰粉磨后,以不同比例与一定细度水泥配合,制成一系列粉煤灰水泥粉体．根据Dinger-Funk数学模型得出粉煤灰水泥粉体最佳颗粒群分布即最紧密堆积颗粒群分布．通过水泥与粉煤灰激光粒度检测结果计算粉煤灰水泥粉体实际颗粒群分布．运用灰色关联分析原理考察粉煤灰水泥粉体实际颗粒群分布与最紧密堆积颗粒群分布的相关性,同时测定粉煤灰水泥标准稠度用水量以及胶砂抗压强度．结果证明：当粉煤灰水泥粉体实际颗粒群分布与最紧密堆积颗粒群分布关联度较高时,相应粉煤灰水泥标准稠度用水量增加较少,胶砂抗压强度发展较理想．     

矿渣粉的粉磨方式对矿渣水泥性能的影响研究

通过激光粒度分析仪（LPS）对球磨和立磨粉磨的矿渣粉粒度分析，旋转粘度计对矿渣水泥流变性能的测量及胶砂强度测定。结果表明：球磨机所加工的矿渣粉比立磨加工的矿渣粉颗粒尺寸分布宽、细颗粒含量高：矿渣粉比表面积相近时，两种矿渣水泥的流变性能相差不大：球磨矿渣水泥的强度比立磨的稍好。     

矿渣粉的粉磨方式对矿渣水泥性能的影响研究

墨西哥绿色建筑协会组织专场演讲会，邀请正在墨西哥参加联合国世界水论坛的中国建设部副部长仇保兴，就中国的建筑节能与绿色建筑的发展发表演讲。仇保兴在演讲中详细介绍了中国绿色建筑发展对世界可持续发展的重大意义、发展目标和基本策略。     

Effect of palm oil fuel ash fineness on the microstructure of blended cement paste

This paper presents the effect of palm oil fuel ash fineness on the microstructure of blended cement paste. Palm oil fuel ash (POFA) was ground to two different finenesses. Coarse and high fineness palm oil fuel ash, with median particle sizes of 15.6 and 2.1 μm, respectively, were used to replace ordinary Portland cement (OPC) at 0%, 20% and 40% by binder weight. A water to binder (W/B) ratio of 0.35 was used for all blended cement pastes. The amorphous ground palm oil fuel ash was characterized by the Rietveld method. The compressive strength, thermogravimetric analysis and pore size distribution of the blended cement pastes were investigated. The test results indicate that the ground palm oil fuel ash was an amorphous silica material. The compressive strengths of the blended cement pastes containing coarse POFA were as high as that of OPC cement paste. Blended cement paste with high fineness POFA had a higher compressive strength than that with coarse POFA. The blended cement pastes containing 20% of POFA with high fineness had the lowest total porosity. The Ca(OH)₂ contents of blended cement paste containing POFA decreased with increasing replacement of POFA and were lower than those of the OPC cement paste. In addition, the POFA fineness had an effect on the reduction rate of Ca(OH)₂. Furthermore, the critical pore size and average pore size of blended cement paste containing POFA were lower than those of the OPC cement paste. The incorporation of high fineness POFA decreased the critical pore size and the average pore size of blended cement paste as compared to that with coarse POFA.     

磨细粉煤灰粉磨制度对其水化行为和强度的影响分析

对不同粉磨制度下得到的磨细粉煤灰进行性能表征,并使用磨细粉煤灰制备水泥浆体,进行强度测试和水化产物物相分析。研究结果表明:设有分选系统的立磨制备的磨细粉煤灰粒度更小,而试验室球磨机在粉磨过程中更多球形颗粒被破坏,更易激发出其火山灰活性,增强其在水泥浆体中的水化程度,从而表现出更高的强度。     

Utilization of beet molasses as a grinding aid in blended cements

This paper investigates the viability of using beet molasses as a grinding aid for blended cements with high volumes of mineral admixtures. Different ratios of beet molasses (0.01–0.05% by weight of cement) were added into a blended cement containing 41% of fly ash and GBFS. The influence of beet molasses on performances of blended cement was studied by comparing with one commercially available, triethanolamine-based grinding aid (TA). The results show that when comparing with the blank cement mixture, the cement containing 0.02–0.03% molasses shows a higher compressive strength at 3 days and 28 days, even exceeding the TA mixture. The improved microstructure of the molasses modified cement paste was also demonstrated by the pore structure and SEM measurements. These improvements are attributed to the better particle size distribution induced by the addition of molasses, indicating the potential application of beet molasses as a good grinding aid.     

Study of the hydration process of quaternary blended cements and durability of the produced mortars and concretes

This study aims to clarify the effect that blended cements with four components have on the hydration process and durability of concrete. Therefore, blended cements with two different proportions of high calcium fly ash, natural pozzolan and limestone have been produced and have been compared with CEM I. Compressive strength was measured at different ages and the hydration kinetics was studied by means of proton nuclear magnetic resonance (NMR-H). Furthermore, the above mentioned cements have been used to produce mortars and concretes and their durability have been determined. The aspects of durability that has been determined are: pore size distribution by means of NMR-H and mercury intrusion porosimetry, penetration of chlorides, carbonation and resistance to sulfates attack. The conclusion of the present study is that quaternary blended cements can perform as well as CEM I cement as far as compressive strength are concerned and they produce durable mortars and concretes.     

Mineralogy of plain Portland and blended cement pastes

The compressive strength and microstructure of blended cement was investigated in this study. The hydration products of cements were identified by means of scanning electron microscopy (SEM) and polarising microscopy (thin section). Results indicated that the blended cement required pozzolanic activity in addition to its cementing property with the addition of 30% material. Aggregations of belite grains were observed which were surrounded by alite. Blended cement exhibited high early-term strength. However, its 3d-age strength is lower than ordinary Portland cement. On the other hand, all blended cement mortars fulfil the compressive strength requirements of TS 24. Hence, it can be said that blended cement can achieve adequate early compressive strength. A reduction in the amount of CSH gel and the porosity of the matrix in mortars were found to be responsible for the poor compressive strength of the cement paste in early the age.     

不同粒径废玻璃粉对水泥胶砂力学性能的影响

采用3种粒径(20、200、2 000目)的废玻璃粉等体积取代水泥胶砂中的标准砂,体积取代率分别为5%、10%、15%、20%,研究玻璃粉粒径和掺量对水泥胶砂的抗压强度和抗折强度的影响,并对玻璃粉水泥胶砂强度随龄期的变化规律进行了分析讨论。结果表明:不同粒径玻璃粉水泥胶砂的强度随玻璃粉掺量的变化规律存在较大的差异;在玻璃粉掺量相同的情况下,掺入较大粒径玻璃粉的水泥胶砂强度明显降低,玻璃粉粒径越小,强度降低程度越小,当玻璃粉粒径达到微米级,水泥胶砂的抗压强度和抗折强度均显著提高;玻璃粉水泥胶砂的抗压强度随龄期增长,早期强度增加的较快,后期发育增速变缓,而抗折强度早期增长的幅度较大,后期发育比较平缓。