利用油页岩渣制备水泥胶凝材料的实验研究

探讨了利用油页岩渣制备水泥的配方,分别对油页岩渣作为水泥生料以及水泥熟料填料的力学性能进行了实验,结果表明：油页岩渣可作为水泥生料,油页岩渣作为熟料的填料比作为生料效果更好。     

Development of calcium sulfate–ggbs–Portland cement binders

Binders manufactured using a blend of gypsum, ground granulated blast furnace slag and Portland cements are technically viable and possess considerable environmental and economic advantages when compared to binders manufactured using Portland cement alone. As such, the evaluation of binders made from these materials offers a promising research focus in the quest to produce technically sound, environmental and economical binders for specialist uses as an alternative to traditional concrete binders of higher carbon footprint. The aim of the test programme was to investigate the viability of a series of binders designed to fulfil particular user needs while having significantly decreased carbon footprints.Two distinct series of binders were designed; the dominant ingredient in the first was calcium sulfate while in the second it was ggbs. Potential applications for both series of binders were considered and the strength development of each binder was analysed. In addition, the effect of water on the gypsum-based binders was analysed, as was the sulfate resistance of the ggbs-based binder.The results of the laboratory tests carried out were varied. For the calcium sulfate-based binders, those manufactured using anhydrite II as the dominant ingredient were found to achieve highest strengths. However these binders were found to be particularly susceptible to moisture-induced deterioration. For the ggbs-based binders, it was found that the early strength development was improved by the addition of small quantities of anhydrite II and gypsum. The strengths and sulfate resistance at later ages remained unaffected. These binders may have significant potential in situations where early strength development is a requirement.     

水泥砂浆韧性改善的试验研究

引入缓慢弯曲试验法,对水泥砂浆的增韧改性进行了试验研究。结果发现,适量掺加沸石矿粉,对水泥砂浆韧性的提高有一定贡献;适量引气剂的掺入,可以在较大程度上提高其断裂能;合理加大砂灰化,也是提高水泥砂浆断裂能（韧性）廉价而有效的方法之一。     

Monitoring lime and cement improvement using spectral induced polarization and bender element techniques

Spectral induced polarization(SIP)and bender element(BE)techniques show a high sensitivity to particle size,particle distribution and content of generated hydration products,which essentially govern the efficiency of ground improvement.In this context,both SIP and BE were integrated on a column setup to monitor the processes of lime and cement stabilization.A 5 mmol/L Na2CO3 solution was injected into the sand-lime mixture to produce CaCO3 precipitation,while deionized water was injected into the sandcement mixture to induce the hydration of cement.The average diameters of the precipitated particles or clusters were calculated from the relaxation time,which was a significant parameter of SIP signals,via the Schwarz equation.Two pairs of BE were used to demonstrate the heterogeneity of the product precipitation,which was probably caused by the location of the inflow and outflow on the SIP-BE column.SIP and BE showed the capability of nondestructively monitoring the spatiotemporal chemical evolution processes,which could be helpful for engineering applications.     

复合助剂改性泡沫石膏的强度和韧性

以石膏为基材,以差皂粉、水泥、引气剂和铝粉膏为复合助剂,以抗折、抗压强度及折压比为指标,采用L9(34)正交试验,测试分析了复合助剂对泡沫石膏强度和韧性的影响。结果表明,复合助剂能提高石膏的折压比,在试验所选的因素水平范围内,复合助剂改性的泡沫石膏折压比为0.48~1.07,韧性明显改善;当复合助剂的组成为差皂粉掺量0.35%、水泥掺量20%、引气剂掺量100%以及铝粉膏掺量1/1300时,泡沫石膏的抗折强度为0.29 MPa,抗压强度为0.27 MPa,折压比为1.07。     

测水泥中SO3碘量法的改进

在水泥的生产过程中,要求控制好水泥中SO3的含量.因此,对SO3测定方法的选用也是很重要的,要使其符合实际,把好水泥质量关.笔者所在水泥厂对出厂水泥一直用重量法测定,而对生产中的出磨水泥SO3用碘量法测定,效果还可以,但也存在着一些问题.结合本厂实际解决了几个实际问题,现和大家一起探讨.     

水泥砂浆断裂韧度的尺寸效应研究

用两种不同配合比的水泥砂浆分别制作了三组几何相似的矩形截面直裂缝三点弯曲梁.在MTS815材料试验机上进行试验,记录了试件的荷载-加载点位移(P-δ)和荷载-裂缝端口张开位移(P-ωCMOD)的全过程曲线.利用最大荷载和初始裂缝长度求得的线弹性断裂韧度存在明显的尺寸效应.为此,基于虚拟裂缝模型,认为裂缝端口张开位移是荷载、自霞和黏聚力共同作用的结果,求解该位移公式得到断裂过程区长度值,用断裂过程区长度修正初始裂缝长度后,再代入三点弯曲梁应力强度因子公式,进而得到尺寸效应程度较弱的等效断裂韧度值.     

多因素耦合作用下水泥胶凝材料劣化试验方法和评价指标的探讨

为研究水泥胶凝材料在多因素耦合作用下的劣化情况,首先要拟定多因素耦合作用的试验方法和提出有效的评价指标,试验引用物理场对水泥基建筑物所处的复杂环境进行了系统分析,结合实际工程和试验设备的可操作性,从理论上探讨了切实可行的多因素耦合作用顺序;在对多因素耦合作用下水泥胶凝材料的劣化程度进行试验验证后,给出了适合多因素耦合作用下水泥胶凝材料劣化试验的必备控制条件;基于水泥胶凝材料的劣化机理,从宏观和微观两个角度对多因素耦合作用下水泥胶凝材料劣化效果的评价指标进行了探讨;最终给出了适用于多因素耦合作用下水泥胶凝材料劣化的试验流程。     

从我国水泥标准的历次修订看水泥质量的发展与提高

1前言 产品标准是产品生产、交易和使用的技术与法律依据,是质量管理的规范基础,产品检验方法既是标准的体现又是质量的保证.我国水泥产品标准及其检验方法的修订综合反映了水泥为混凝土服务的发展历程,反映了水泥工业的技术进步、生产水平和发展方向.它有效地促进了我国水泥生产工艺的不断革新和产品质量的持续提高.     

浅议水泥企业质量管理的改进

一个企业的生命力在于其产品的市场占有率,而市场占有率在很大程度上取决于产品的魅力质量(信誉、服务及性价比).水泥作为产品,当然也符合这个规律,并且还有其特殊性.因为水泥只是一般初级产品,它的价值(性能)要通过其制品或工程才能完全体现出来;工程一旦出现事故,对水泥厂家、建设单位和施工方都会造成严重的不良影响和损失,即便水泥质量没有问题,也会因人们的习惯心理对水泥产品本身产生怀疑.更为甚者,有些不良用户借此机会非法制造或扩大质量事故事态,以索取巨额赔偿.因此,水泥企业的质量管理工作不仅要把重点放在制造环节,而且更多地还应体现在售后环节上.     

改性菱镁水泥制品的性能及其改善措施

介绍了改性菱镁水泥制品的各种性能、反应机理以及改善措施。     

Hydraulic binders of Fluorgypsum–Portland cement and blast furnace slag,stability and mechanical properties

The effect of various additives (Ca(OH)₂, K₂SO₄, Na₂SO₄, Al₂(SO₄)₃) was evaluated on the hydraulic character and stability of pastes of 50–75% Fluorgypsum, 15–30% Portland cement and 10–20% Blast furnace slag. Characterization included length changes, compressive strength, SEM, DTA and XRD. The combination of Na₂SO₄ and Al₂(SO₄)₃ favored early strength but caused detrimental expansion and strength losses after 90 days; whereas the use of only K₂SO₄ was favorable for strength and dimensional stability. The type of additive had a more important effect on stability and strength than the amounts of cement and slag. XRD indicated the presence of anhydrite, gypsum, ettringite, CaCO₃ and an unidentified phase, the interaction of these is proposed to explain the behavior of the cements investigated. SEM showed that cement and slag reacted forming C–S–H that enhanced the hydraulic character by engulfing the gypsum crystals.     

Chemical stabilization of scrap metal yard contaminated soil using ordinary portland cement: Strength and leachability aspects

In this study, the strength development and lechability aspects of metal-contaminated soil treated with ordinary portland cement (OPC) were investigated. The soil was collected from a scrap metal yard within the outskirts of Kuala Lumpur, Malaysia. Metal composition analysis indicated that the predominant metals present in the soil were iron (42,194 mg/kg), aluminium (8874 mg/kg), zinc (690 mg/kg), lead (428 mg/kg), copper (107 mg/kg) and chromium (52 mg/kg). The contaminated soil was treated with OPC using cement-to-dry soil (C/S_d) ratios of 0.5, 1 and 2. The effectiveness of the treatment was evaluated by performing unconfined compressive strength (UCS) as well as crushed and whole block leaching (WBL) tests on the treated soil. The treatment results were compared to the solidified waste acceptance criteria which were compiled based on the regulatory waste disposal limit at a disposal site in the United Kingdom and the maximum concentration of contaminants for toxicity characteristic of solid wastes from United States Environmental Protection Agency. Results indicated that chemical stabilization of metal-contaminated soils using OPC was effective for prevention of metal leaching from both disintegrated samples subsequent to years of weathering (crushed block) and intact samples (whole block) into the environment.     

路面机制砂水泥混凝土的强度与耐磨性研究

研究了水灰比、细度模数、石粉含量、洛杉矶磨耗等因素对路面机制砂水泥混凝土强度与耐磨性的影响,并与河砂混凝土进行了比较.研究结果表明:机制砂混凝土的耐磨性与强度密切相关,强度越高,耐磨性越好,同等水灰比下机制砂混凝土的耐磨性优于河砂;机制砂石粉含量在20%范围对混凝土的强度与耐磨性无不利影响.随着石粉含量的增加,机制砂混凝土的强度呈先增大后降低的趋势,磨损量减小;机制砂适当大的细度模数有利于混凝土的耐磨性;耐磨性越好的机制砂配制的混凝土磨耗值越小.     

高韧性聚合物水泥喷浆技术及巷道工程应用研究

针对传统水泥喷射混凝土技术存在施工环境不友好、施工劳动强度大、喷浆层易围岩脱空、开裂和垮塌等问题,研究了聚合物改性高韧性水泥喷浆材料和系统工艺技术,对聚合物添加量为0~50%的水泥喷浆材料力学性能及微观形貌进行探讨,制备得到韧性较好的聚合物改性水泥喷浆材料,并设计出配套的连续高效喷涂设备和工艺技术,并在某隧洞工程进行了应用试验。结果证明,该材料具有优异的围岩喷护效果,对围岩整体支护防护有较好的协同作用,且施工作业绿色、高效。     

水泥销售发运流程的分析与改进

通过对水泥销售发运实例流程的分析,提出其改进方案。改进后的流程增加了发货计划、进厂秩序管理、袋装提货车辆二次过磅、发货单双重约束等核心环节,提高了水泥销售发运流程的管控严密性及资源控制能力,维护了企业与客户的利益,解决了企业的管理难题。     

用胶结料提高混凝土的耐久性

混凝土是一种用途相当广泛的建筑材料。如何提高混凝土的耐久性?这个问题已经引起世界各国建筑工程界的严重关切。在混凝土中掺入硅灰、粉煤灰和磨细的粒状高炉矿渣等工业副产品，即可提高混凝土抵抗各种侵蚀的耐久性，而且变废为宝，有利于环保节能，这是一条大有前途的利国利民的重大举措。     

散装水泥车进料口结构改进

散装水泥车是一种在工业、建筑业等方面得到广泛应用的专用汽车,适用于水泥、石灰粉、粉煤灰等颗粒直径不大于01mm粉粒干燥物料的运输。主要由汽车底盘、罐体总成、管路系统及传动装置等组成。其中罐体总成由罐体、进料口、流态化床、出料管总成、进气管及其它附件组成。在罐体     

浅谈本公司实施水泥新标准的几点质量改进措施

我公司在新标准的过渡中,从去年７月份起就对出厂水泥和熟料用同一样品做了大量的新、旧标准平行对比试验,想摸清新、旧标准的对应关系。同时也改变了一些工艺参数,以便探索不同的配比,不同工艺条件对新、旧标准强度的影响。１熟料煅烧质量的好坏是影响ＧＢ强度与ＩＳＯ强度的重要因素我们通过较长时间对同一样品,同时进行ＧＢ强度与ＩＳＯ强度的对比检验发现,不同时期ＧＢ强度与ＩＳＯ强度差值大小不同,有时同一样品ＧＢ强度与ＩＳＯ强度差值较小只有４—５ＭＰａ,而另一时期竟可高达１０ＭＰａ,根据其差值大小,划分阶段,统计其…     

Strength characterization of cohesionless soil treated with cement and polyvinyl alcohol

Lime, cement, and bitumen are well-known traditional binders for improving the bearing capacity of soils. However, the production of these binders results in a massive impact on the environment due to the emission of greenhouse gases, such as carbon dioxide (CO₂), nitrous oxide (N₂O), and methane (CH₄). In this study, a novel cement–polyvinyl alcohol (PVA) mixture is proposed to fabricate strong composite geomaterials. The advantage of the proposed materials is that they can increase the unconfined compressive strength (UCS) and, combined with cement hydration, producing PVA glue, can be used to fill up the soil pores. Laboratory tests indicate a threefold increase in UCS with the cement–PVA-combined mixture compared to a cement-stabilized one. The results of scanning electron microscope (SEM) observations suggest that the cement–PVA composite can ameliorate the pore structure that is more solid than the cement-stabilized one. Moreover, by curing at 80 °C, the strength of the cement–PVA stabilized soil decreases by threefold, plateauing at the same strength as the non-PVA stabilized soil. In addition, the results of cyclic thermal exposure tests suggest that, with the increase in the number of heating/cooling cycles, the UCS gradually decreases compared to the initial one. However, the loss of UCS is less than 25 % under the three cycles of exposure. Thus, these composites have the potential to promote urban renewal projects in an ecofriendly manner.