压汞测孔评价磷渣-水泥浆体材料孔隙分形特征的试验

用混沌分形理论结合压汞测孔技术,直接测试评价了磷渣-水泥浆体材料孔隙的显微结构特征,计算出了对应的分形维数,并对普通水泥浆体与掺磷渣的水泥浆体孔隙的分形特征进行了比较;同时探讨了孔体积分维数与孔隙率、孔表面积、孔分布及磷渣掺量的关系.研究表明,磷渣-水泥浆体的孔结构具有明显的分形特征,孔体积分形维数在2.4~2.8之间;掺磷渣的水泥浆体不仅具有粗孔细化的效果,而且孔隙的分形特征也有了明显的改善;在磷渣掺量大于30%时,其分维数、孔隙率与小于20 nm的微孔数有明显的突变性.     

多孔介质孔隙结构重构及水蒸气传递特性

采用随机生长法分别构造了各向同性、各向异性的孔隙率相同,孔径分布和孔隙表面分形维数不同的多孔介质,探索了在多孔介质孔隙率相同的情况下,微观孔隙结构对孔隙内湿传递过程的影响。结果表明：决定多孔介质内部输运特性的孔隙结构参数,除孔隙率以外,孔径分布和孔隙表面分形维数等参数对多孔介质孔隙中水蒸气扩散过程的影响显著;孔隙率相同,孔径分布和孔隙表面分形维数不同的3种各向同性和3种各向异性多孔介质的水蒸气扩散浓度最大差别分别为30.6%和23.3%;各向同性多孔介质的小孔分布率越大,孔隙表面分形维数越大,说明孔隙的连通性和水蒸气在多孔介质孔隙中的扩散性能越好;各向异性多孔介质（水蒸气扩散的方向垂直于其生长率较大的方向）的大孔分布率越大,孔隙表面分形维数越小,水蒸气在多孔介质孔隙中的传递性能越好。     

聚合物对发泡水泥制品孔结构和性能影响

以快硬硫铝酸盐水泥作为胶凝材料,干密度为200 kg/m3的发泡水泥为对象,研究乳液和胶粉对发泡水泥孔隙率、孔径分布、孔径大小和强度的影响.结果显示:随着聚合物掺量的增加,发泡水泥制品的孔隙率不随聚合物掺量的增加而发生变化,气孔的孔径逐渐变小,强度不断增大.当乳液和胶粉外掺量分别为2.5%时,发泡水泥28d的抗压强度、抗折强度和垂直表面拉伸强度分别增加8%、13%、28%和5%、10%、25%.     

Comparison of hydration properties between cement-GGBS-fly ash blended binder and cement-GGBS-steel slag blended binder

The hydration properties of cement-GGBS-fly ash blended binder and cement-GGBS-steel slag blended binder were compared. The experimental results show that the hydration rate of cement-GGBS- steel slag blended binder is higher than that of cement-GGBS-fly ash blended binder within 28 days, but lower than the latter after 28 days. The hydration of cement-GGBS-steel slag blended binder tends to produce more Ca（OH）2 than the hydration of cement-GGBS-fly ash blended binder, especially at late ages. Cement-GGBS- steel slag mortar exhibits higher strength than cement-GGBS-fly ash mortar within 28 days, but at late ages, it exhibits similar compressive strength with eement-GGBS-fly ash mortar and even slightly lower bending strength than cement-GGBS-fly ash mortar. Cement-GGBS-steel slag paste has finer early pore structure but coarser late pore structure than cement-GGBS-fly ash paste. Cement-GGBS-steel slag paste can get satisfied late pore structure and cement-GGBS-steel slag mortar can get satisfied late strength as compared with pure cement paste and pure cement mortar, respectively.     

Compressive Strength, Pore Size Distribution and Chloride-ion Penetration of Recycled Aggregate Concrete Incorporating Class-F Fly Ash

The effects of fly ash on the compressive strength, pore size distribution and chloride-ion penetration of recycled aggregate concrete were investigated. Two series of concrete mb：tures were prepared. The concrete mixtures in series I had a water-to-binder ratio and a cement content of 0.55 and 410 kg/ m^3 , respectively. The concrete rnixtures in series II had a water-to-binder ratio and a cement content of 0.45 and 400 kg/ ml respectively. Recycled aggregate was ased as 20% , 50% , and 100% replacements of natural coarse aggregate in the concrete mixtures in both series. In cutdition, fly ash was used as 0% , 25% and 35% by weight replacements of cement. The results show that the compressive strengths of the concrete decreased as the recycled aggregate and the fly ash contents increased. The total porosity and average porosity diameter of the concrete increased us the recycled aggregate content increased. Furtherrruore , an increase in the recycled aggregate content decreased the resistance to chloride ion penetration. Nevertheless, the replacement of cement by 25% fly ush improved the resistance to chloride ion penetration and pore diameters and reduced the total porosity of the recycled aggregate concrete.     

Effect of Sand Content on Strength and Pore Structure of Cement Mortar

The effects of four sand contents on the compressive, flexural and splitting-tensile strength of cement mortars were evaluated. Moreover, we experimentally investigated the pore structure of cement mortar brought about by changing the sand content and water/cement ratio. The changes in the pore structure were quantified by measuring the porosity and pore size distribution obtained by using mercury intrusion porosimetry(MIP) technique. The test results show that the strengths of cement mortar increase with increasing sand content. It is also suggested that the traditional water/cement ratio law can be applied to cement mortar with different sand contents, provided that a slight modification is introduced. Sand content is an important parameter influencing the pore structure of cement mortar. Moreover, there is a good relationship between the pore structure and strength of cement mortar.     

钢铁渣粉对水泥基材料性能影响机理研究

通过对马钢钢渣粉化学成分、X-射线衍射原材料分析,探究了钢渣粉对水泥基材料力学性能、体积稳定性的影响.试验结果表明:随着钢渣粉掺量的增加,力学性能下降明显,当掺量为10％时,与空白样相比抗压强度略有下降,当掺量为20％时,抗压强度下降幅度较大;钢渣对水泥基材料体积稳定性影响明显,相同龄期随着钢渣掺量增大,自由膨胀率升高.通过化学成分及扫描电镜分析,f-CaO是导致水泥基材体体积膨胀的根源.     

Properties of Steel Slag and Stainless Steel Slag as Cement Replacement Materials: A Comparative Study

To enhance the understanding about the utilization of steel slags as a cementitious material, we comparatively studied the chemical, mineralogical and morphological properties of two types of steel slag; basicoxygen-furnace carbon slag(BOF C) and electric-arc-furnace stainless steel slag(EAF S). Moreover, we studied the standard consistency, setting time and the effect of the slag replacement ratios on the fluidity and compressive strength of blended cement mortar. The experimental results showed that BOF C had higher alkalinity, higher pH value and more hydraulic phases than EAF S. Both types of slag showed water reduction effect due to its high fineness. Neat BOF C paste showed flash set and acceleration in the initial setting time of blended cement especially at high slag proportions. However, EAF S prolonged the setting time of blended cement even at low slag proportions. The pH values for blended cement contained 50% BOF C or EAF S were lower than those of pure cement paste. Despite of slag type, compressive strength gradually decreased with increasing slags content. The strength of BOF C mortar was higher than that of EAF S mortar with the same replacement ratio for the same age. Slag activity index demonstrated that BOF C and EAF S conformed to the Chinese National Standard(GB/T 20491-2006) requirements for steel slag as grade one and grade two, respectively.     

超细钢渣粉体分形特征的测试与评价

对钢渣进行不同程度的超细加工，应用分形理论探讨钢渣粉体粒度分布的特征，并分析评价其形态，细度对水泥基材料早期和后期活性的影响。     

A Blended Cement Containing Blast Furnace Slag and Phosphorous Slag

Blended cement comaining blast furnace slag( BFS ) and phosphorous slag( PS) is a new kind of cement. The total content of blended materials could increase if two additives were used. Using the same admixtures , the properties of the blended cement with 70% additives could reach the standard of 525-grade slag cement according to GB. The strength of cement with 80% additives could reach the standard of 425-grade slag cement. The tests of strength, pore structure, hydration products, inhibiting alkali-aggregate reaction, resistance to sulfate corrosion of BFS-PSC were performed.     

基于NMR和SEM技术研究陆相页岩孔隙结构与分形维数特征——以松辽盆地长岭断陷沙河子组页岩为例

为了表征陆相页岩的孔隙结构和分形特征,选取松辽盆地长岭断陷沙河子组陆相页岩作为研究对象,通过X射线衍射(XRD)分析、扫描电镜(SEM)图像分析、核磁共振(NMR)实验,运用分形维数理论,讨论NMR分形维数与矿物组成、地球化学参数、物性参数之间的相互关系,并且通过SEM图像提取技术定量化研究页岩储层孔隙特征。结果表明:沙河子组陆相页岩具有多种孔隙类型、孔径分布复杂、非均质性较强的特点。基于弛豫时间截止值,可将NMR分形维数划分为束缚流体孔隙分形维数(0.060 9～1.420 4)和可动流体孔隙分形维数(2.964 0～2.986 9)。矿物组成与分形维数的关系显示石英含量与束缚流体孔隙分形维数成负相关关系,黏土矿物含量与束缚流体孔隙分形维数成正相关关系; NMR分形维数与有机质含量呈线性相关,与成熟度不存在明显相关性; 这说明矿物组成和有机质含量对NMR分形维数起明显的控制作用。储层物性方面,NMR分形维数与孔隙率成线性负相关关系,而与渗透率成正相关关系,说明NMR分形维数能够作为衡量物性的重要指标。总体来说,SEM图像分形维数可以用来反映孔隙形态的多样性和页岩孔隙的发育程度; NMR分形维数与储层物性之间的关系可用于评价页岩储层质量。     

Effect of coal gangue with different kaolin contents on compressive strength and pore size of blended cement paste

The effects of activated coal gangue on compressive strength, porosity and pore size distribution of hardened cement pastes were investigated. Activated coal gangue with two different kaolin contents, one higher and one lower, were used to partially replace Portland cement at 0%, 10%, and 30% by weight. The water to binder ratio（w/b） of 0.5 was used for all the blended cement paste mixes. Experimental results indicate that the blended cement of activated coal gangue mortar with higher kaolin mineral content has a higher compressive strength than that with lower kaolin mineral content. The porosity and pore size of blended cement mortar were significantly affected by the replacement of activated coal gangue.     

镁渣替代石灰石配料外加剂的选择及掺量的研究

镁渣替代石灰石配料制备水泥熟料时，分别掺入和同时掺入2种自制外加剂，通过生料易烧性实验和熟料物理性能及XRD图谱的测定，确定外加剂和镁渣的最佳掺量。实验结果表明：同时掺入2种外加剂能大幅度改善生料易烧性，此时镁渣可以代替20％石灰石，烧成的硅酸盐水泥28d强度可达65．2MPa。     

测度关系法评价水泥基材料孔隙SEM分形特征

目的以测度关系法对混凝土孔隙的SEM图像分形维数进行精细测量和计算,分析其孔隙分形特征.方法以砂浆中集料界面区域孔隙SEM照片为例,用测度关系法、分别以250 nm和200 nm,125 nm和100 nm不同尺度的网格测试评价界面孔隙的分形维数,与改变粗视化方法进行比较.结果传统的改变粗视化程度的方法与网格边长的关系太大,网格边长受测试条件的限制,导致误差过大,而采用测度关系法计算SEM图像孔隙显微结构分形维数比较可靠.采用测度关系法用边长差异为50 nm网格测试其孔隙分形维数为1.293 5,用边长差异为25 nm的网格测试的孔隙分形维数为1.280 9,误差只有0.012 6;当考虑中间水化产物时,用边长差异为50 nm网格测试其孔隙分形维数为1.577 3,用边长差异为25 nm网格测试的孔隙分形维数为1.570 1,误差只有0.0072;此外,考虑中间水化产物后,孔隙的分形维数增大,表明孔隙复杂程度明显增大.结论采用测度关系法计算分形维数比改变粗视化程度方法更为精细.分形理论分析评价多孔材料SEM图像孔结构分形特征是有效的,对于深入了解水泥基复合材料的内部微结构、提升性能、扩大应用具有重要意义.     

掺大量混合材水泥组分优化与性能研究

研究了在混磨工艺下,大掺量混合材水泥中粉煤灰、矿渣的优化比例.固定混合材总量为44%和粉磨时间不变,对不同粉煤灰、矿渣用量的水泥颗粒级配和力学强度进行了测试,同时分析了掺混合材对水泥石孔隙结构和微观形貌的影响.结果表明：矿渣掺量占总混合材料用量的27%～34%时,水泥颗粒级配和力学性能最佳.掺配比例合理的大量混合材使水泥石孔隙结构细化,水泥石中大于100μm的粗孔明显减少或消失,即显著增加了小于0.1μm的细孔含量;同时可使水泥石微观结构均匀致密,大量层片状聚集的氢氧化钙晶体消失.     

双重分形多孔介质孔隙率的研究

根据双重分形多孔介质孔隙分布分形维数D与孔隙迂曲分形维数DT的定义和计算公式,推导了多孔介质孔隙率的计算公式.通过孔隙率计算公式的函数图像分析了双重分形维数D和DT的变化对孔隙率的影响,分析结果表明孔隙率随多孔介质双重分形维数D和DT的增加而增大;多孔介质最大孔隙直径越大孔隙率增加的就越慢;当D＋DT〈3时,多孔介质最大孔隙直径越大孔隙率就越大,但当D＋DT〉3时则相反,多孔介质最大孔隙直径越大孔隙率反而越小,D＋DT=3是特殊点,令D＋DT→3时的孔隙率极限值为它的孔隙率.     

镁渣等工业废渣应用现状的研究及前景分析

镁渣矿物属于介稳的高温型结构,结构中存在活性的阳离子,所以,镁渣本身具有很高的水化活性,水化后生成水化硅酸钙凝胶,镁渣作为破胶凝材料是可行的,镁渣中的[SiO4]4-更易丢失,链断裂,形成类似于有机-无机杂化物的结构,在镁渣中掺入一定的硅酸盐水泥或磨细硅酸盐水泥熟料和磨细矿渣,以提高镁渣胶凝材料的耐久性,镁渣作为砂浆的胶结材料是非常理想的,镁渣不但可以提高砂浆的和易性,而且还可以提高砂浆的强度和耐久性,镁渣中掺入一定量的轻骨料,可制作轻质保温墙体材料或制成屋面材料。     

锰渣掺合料对海工混凝土耐久性的影响

研究了锰渣的组成、结构等基本性能及其对海工混凝土耐久性的影响.所用水淬锰渣碱度系数1.09、质量系数1.71,具有潜在水硬活性.含α′-C2S胶凝矿物,其玻璃体含量和活性指数均约为80％.从水胶比、浆集比、水泥用量等配合比设计参数优化出发,使用锰渣掺合料和萘磺酸甲醛高效减水剂配制了力学性能良好的C40海工混凝土.用5倍正常海水浓度的模拟海水溶液对掺锰渣混凝土进行了侵蚀试验,以考察其耐海水腐蚀性.研究发现,掺锰渣混凝土在人工海水侵蚀及50次冻融循环后质量损失、强度损失均较小,抗渗性有所改善.由于所用水淬锰渣对改善混凝土耐久性有重要作用,其可作为矿物掺合料应用于近海及海洋环境混凝土工程.     

钢渣在水泥熟料烧成中的作用及其机理

通过对原材料化学组成的分析，发现在水泥熟料烧制中钢渣不仅可以作石灰质及铁质原料，而且可以作为“晶种”，有利于水泥熟料的煅烧。因此将钢渣作为独立组分，利用自编全组分水泥配料计算系统在较大率值范围内，进行大量计算并分析规律，选取配比进行烧成实验。结果表明：在生料中掺入钢渣不仅可以降低硅氧率，明显减少f-CaO含量，提高熟料质量，而且能够降低环境负荷，具有良好的经济效益、社会效益和环境效益。     

The Pore Structure and Hydration Performance of Sulphoaluminate MDF Cement

1　IntroductionReducingporositycouldimprovethestrengthofma terials ,butitisnotenoughthatthechangeofthestrengthofthematerialsisonlysubjectedtothechangeofporosi ty .Thereforetheporedistributionconceptisintroduced .Weeventhinkthattherelationbetweentotalporos…