摘   要：研究了超细粉煤灰掺量对低水胶比复合胶凝材料浆体流动性的影响，分析了浆体流动性与流变性能的关系。结果表明：在相同水胶比和硅灰掺量下，随着超细粉煤灰掺量的增加，浆体流动度增大，流动时长先缩短后延长，平均流动速率先提高后下降，浆体的黏度系数减小，屈服应力增大，剪切增稠性增强；在相同超细粉煤灰掺量下，浆体的流动度-黏度系数和流动度-屈服应力均呈负相关，黏度系数或屈服应力减小，浆体的流动度增大；在相同流动度下，当超细粉煤灰掺量较高时，浆体的黏度系数减小，屈服应力增大；浆体的流动度同时受其黏度和变形能力的影响。 Abstract: The influence of superfine fly ash content on the fluidity of low water-binder ratio composite cementitious material pastes was studied. The relationship between fluidity and rheological properties of pastes was analyzed. The results show that at the same water-binder ratio and content of silica fume, the flow spread of pastes increases, and flowing time of pastes shortens first and then lengthens, and average flowing rate of pastes increases first and then decreases with the increase of substituted rate of cement by superfine fly ash, and the viscosity coefficient of pastes decreases while their yield stress remains increasing. At the same content of superfine fly ash, both the relationships of flow spread and viscosity coefficient as well as yield stress of pastes are negative, and viscosity coefficient or yield stress decreases, and the fluidity of pastes increases. At the same fluidity, when the content of superfine fly ash is high, the viscosity coefficient of the pastes decreases and the yield stress increases. The fluidity of pastes is affected by both its viscosity and deformation capacity.

阎培渝,黄静.超细粉煤灰对低水胶比复合胶凝材料浆体流动性的影响[J].混凝土与水泥制品,2023(7):1-6. YAN P Y,HUANG J.The effect of superfine fly ash on the fluidity of composite cementitious material paste with low water-binder ratio[J].China Concrete and Cement Products,2023(7):1-6.

吕奇峰,陈安国,戴鹏飞.3D打印植生混凝土pH值的影响因素研究[J].混凝土与水泥制品,2023(7):8-12. LYU Q F,CHEN A G,DAI P F.Study on the influencing factors on the pH value of 3D printed planting concrete[J].China Concrete and Cement Products,2023(7):8-12.

摘   要：研究了纳米偏高岭土（Metakaolin，以下简称MK）对新拌水泥浆体絮凝结构及触变性的影响，通过测试水泥浆体的流变性能，获取了随时间变化的流变指标（屈服应力、黏度和触变性），测试了不同纳米MK掺量（0、1%、2%、3%）水泥浆体的水化热。此外，基于统计方法，确定了不同纳米MK掺量水泥浆体的絮凝结构重建速率。结果表明：适量的纳米MK（1%~2%）能显著提高水泥浆体的絮凝结构重建速率，并有效改善水泥浆体的触变性。 Abstract: The effect of metakaolin(hereinafter referred to as MK) on the thixotropy of cement paste and the reconstruction rate of the flocculation structure of fresh cement paste were studied. By testing the rheological properties of cement paste, the rheological indexes (yield stress, viscosity and thixotropy) that change with time were obtained, and the hydration heat of cement paste with different nano-MK content（0, 1%, 2%, 3%） was tested. In addition, statistical methods were utilized to determine the flocculation structure reconstruction rate of cement paste with different nano-MK content. The results indicate that appropriate content of nano-MK (1%~2%) can significantly improve the flocculation structure reconstruction rate of cement paste, and effectively enhances the thixotropy of cement pastes.

张利民,张云升,张宇.掺纳米偏高岭土水泥浆体的触变性研究[J].混凝土与水泥制品,2023(7):13-17. ZHANG L M,ZHANG Y S,ZHANG Y.Study on thixotropy of cement paste mixed with nano-metakaolin[J].China Concrete and Cement Products,2023(7):13-17.

摘   要：研究了不同活性MgO含量（60.4%、46.7%、45.9%）对改性硫氧镁水泥强度的影响规律，并结合XRD、SEM等方法分析了其影响机理。结果表明：改性硫氧镁水泥试件的抗压强度均随n（MgO）∶n（MgSO4）的增大而增大；用活性含量为45.9%的MgO制备的水泥试件各龄期抗压强度均高于活性含量为46.7%和60.4%的MgO；改性硫氧镁水泥样品的主要成分为MgO、Mg(OH)2和5Mg(OH)2·MgSO4·7H2O 相（5·1·7相），随着养护时间的延长，5·1·7相的衍射峰增强；样品内生成大量针棒状晶体，存在较多空隙。 Abstract: The effect of different active MgO content(60.4%、46.7%、45.9%) on the strength of modified magnesium thioxide cement were studied, and the influence mechanism was analyzed by XRD, SEM and other methods. The results show that the compressive strength of the modified magnesium thioxide cement specimens with different active MgO content increases with the increase of n(MgO)∶n(MgSO4). The compressive strength of cement samples prepared with 45.9% active MgO is higher than that of 46.7% and 60.4% at each age. There are MgO、Mg(OH)2 and 5Mg(OH)2·MgSO4·7H2O(5·1·7 phase) in modified magnesium thioxide cement samples. The longer curing time, the higher diffraction peak of 5·1·7 phase. There are needle-like crystals in the sapmles and there are much pores in it.

刘冲昊,岳雪涛,翟庆振,等.活性MgO含量对改性硫氧镁水泥强度的影响及机理分析[J].混凝土与水泥制品,2023(7):18-22. LIU C H,YUE X T,ZHAI Q Z,et al.Effect and mechanism analysis of active MgO content on the strength of modified magnesium thioxide cement[J].China Concrete and Cement Products,2023(7):18-22.

摘   要：研究了微珠掺量（0、4%、8%、12%、16%）对高石粉含量机制砂C60混凝土的工作性、力学性能和耐久性能的影响。结果表明：掺入适量的微珠能改善高石粉含量机制砂C60混凝土拌合物的流动性，降低1 h坍落度损失和倒筒排空时间，提高力学和耐久性能；当微珠掺量为8%~12%时，高石粉含量机制砂C60混凝土的综合性能最佳。 Abstract: The effects of the contents of microbeads(0, 4%, 8%, 12%, 16%) on workability, mechanical properties and durability of C60 manufactured sand concrete with high stone powder content were studied. The results show that adding proper content of microbeads can improve the fluidity of the concrete mix with high stone powder content, reduce the slump loss in 1 h and the empty time of the backward cylinder, and improve the mechanical and durability properties of concrete. When the content of microbeads is 8%~12%, the comprehensive performance of C60 manufactured sand concrete with high stone powder content is the best.

王振华.微珠对高石粉含量机制砂C60混凝土性能的影响[J].混凝土与水泥制品,2023(7):23-25,30. WANG Z H.Effect of microbeads on properties of C60 manufactured sand concrete with high stone powder content[J].China Concrete and Cement Products,2023(7):23-25,30.

摘   要：分别采用烯丙基聚氧乙烯醚（HPEG）、甲基烯丙基聚氧乙烯醚（TPEG）和乙二醇单乙烯基聚氧乙烯醚（EPEG）三种聚醚大单体合成了聚羧酸减水剂（PCE），对比研究了所合成的PCE对混凝土流变性能、气泡特征及其经时演化、硬化混凝土外观气泡的影响规律。结果表明：EPEG-PCE与TPEG-PCE的减水率及对混凝土和易性的影响均优于HPEG-PCE，且掺EPEG-PCE新拌混凝土湿筛砂浆的流变参数经时变化小；掺TPEG-PCE和HPEG-PCE试件的气泡参数主要在30~60 min和0~30 min内变化，而掺EPEG-PCE的试件则在0~90 min无明显气泡突变阶段，对尺寸≤500 μm的气泡稳定性影响顺序为TPEG组>HPEG组>EPEG组；掺不同大单体PCE试件的表观气泡含量相当，但TPEG组大气泡最多，EPEG组最少。 Abstract: Polycarboxylate superplasticizer(PCE) was synthesized with 3 kinds of polyether macromers, namely allyl polyoxyethylene ether (HPEG), methylallyl polyoxyethylene ether (TPEG) and ethylene glycol monovinyl polyoxyethylene ether (EPEG), respectively. The influence of synthesized PCE on the rheological performance of concrete, the characteristics of bubbles and their evolution over time, and the appearance of bubbles in hardened concrete were compared and studied. The results show that the water reduction rate of EPEG-PCE and TPEG-PCE and their influence on the workability of concrete are better than those of HPEG-PCE, and the rheological parameters of wet-screened mortar for fresh concrete mixed with EPEG-PCE change little over time. The bubble parameters of TPEG-PCE and HPEG-PCE samples mainly change in 30~60 min and 0~30 min, while the samples with EPEG-PCE have no obvious bubble mutation stage in 0~90 min. The order of bubble stability with size ≤500 μm is TPEG group>HPEG group>EPEG group. The apparent bubble content of the samples mixed with different macromonomer PCE is the same, but the TPEG group samples have the most large bubbles, and the EPEG group samples have the least.

姜骞,吴东阳,苏昂,等.聚醚类聚羧酸减水剂的合成及其对混凝土性能的影响[J].混凝土与水泥制品,2023(7):26-30. JIANG Q,WU D Y,SU A,et al.Preparation of typical polyether-type polycarboxylate superplasticizers and analysis of its influence on concrete properties[J].China Concrete and Cement Products,2023(7):26-30.