摘   要：以矿渣、钢渣、脱硫石膏、粉煤灰为主要原材料制备了固废基胶凝材料，研究了粉磨时间（5、10、15 min）对固废基胶凝材料比表面积、粒度分布、标准稠度用水量和胶砂抗压强度的影响，并通过灰色关联分析方法探究了固废基胶凝材料的粒度分布与标准稠度用水量和抗压强度之间的关联度。结果表明：随着粉磨时间的增加，固废基胶凝材料的细度、比表面积、标准稠度用水量和胶砂抗压强度均增大；固废基胶凝材料的标准稠度用水量和胶砂的抗压强度均与粒度小于20 μm的颗粒含量呈正相关，与粒度大于等于20 μm的颗粒含量呈负相关；适当减少粒度10~20 μm的颗粒含量或增加粒度20~32 μm的颗粒含量，均可在一定程度上降低固废基胶凝材料的标准稠度用水量；增加粒度0~3 μm、10~20 μm的颗粒含量分别有助于提高胶砂的3 d、28 d抗压强度。 Abstract: Solid waste based cementitious materials were prepared by using slag, steel slag, desulfurization gypsum, and fly ash as the main raw materials. The effects of grinding time(5, 10, 15 min) on the specific surface area, particle size distribution, and water requirement of normal consistency of solid waste based cementitious materials, and compressive strength of the mortar were studied. The correlation degree between particle size distribution of solid waste based cementitious materials and water requirement of normal consistency, and compressive strength was explored through grey correlation analysis method. The results show that as the grinding time increases, the fineness, specific surface area, and water requirement of normal consistency of solid waste based cementitious materials, and compressive strength of the mortar all increase. The water requirement of normal consistency of solid waste based cementitious materials and the compressive strength of the mortar are positively correlated with the content of particles with particle size less than 20 μm, and negatively correlated with the content of particles with particle size greater than or equal to 20 μm. By appropriately reducing the content of particles with particle size of 10~20 μm or increasing the content of particles with particle size of 20~32 μm, the water requirement of normal consistency of solid waste based cementitious materials can be reduced to a certain extent. Increasing the content of particles with particle size of 0~3 μm and 10~20 μm respectively helps to improve the 3 d and 28 d compressive strength of the mortar.

张艳佳,张广田,于海洋,等.固废基胶凝材料的粒度分布与其性能的关联度[J].混凝土与水泥制品,2024(4):87-90,95. ZHANG Y J,ZHANG G T,YU H Y+,et al.Correlation degree between particle size distribution and performance of solid waste based cementitious materials[J].China Concrete and Cement Products,2024(4):87-90,95.

摘   要：研究了粉煤灰单掺、粉煤灰与矿渣粉或降黏剂复掺对主塔C60大体积混凝土工作性、力学性能、绝热温升和收缩性能的影响。结果表明：掺入适量降黏剂提高了混凝土的流动性，而掺入矿渣粉降低了混凝土的流动性，但仍满足施工要求；与单掺粉煤灰的试验组相比，复掺适量降黏剂提高了混凝土的抗压强度和弹性模量，降低了绝热温升和自收缩，对劈裂抗拉强度和干燥收缩的影响较小，而复掺适量矿渣粉后，混凝土的7 d抗压强度略有降低，28 d、60 d抗压强度增大，弹性模量增大，绝热温升和干燥收缩降低，28 d劈裂抗拉强度和自收缩变化不大。 Abstract: The effects of single addition of fly ash, compound addition of fly ash and slag powder or viscosity reducer on the workability, mechanical properties, adiabatic temperature rise, and shrinkage performance of C60 mass concrete for main tower were studied. The results show that adding an appropriate content of viscosity reducer improves the flowability of concrete, while adding slag powder reduces the flowability of concrete, but still meets the construction requirements. Compared with the experimental group with a single addition of fly ash, adding an appropriate content of viscosity reducer increases the compressive strength and elastic modulus of concrete, reduces adiabatic temperature rise and self shrinkage, and has a smaller impact on splitting tensile strength and dry shrinkage. However, after adding an appropriate content of slag powder, the 7 d compressive strength of concrete slightly decreases, while the 28 d and 60 d compressive strength increase, the elastic modulus increases, the adiabatic temperature rise and dry shrinkage decrease, and the 28 d splitting tensile strength and self shrinkage do not show significant changes.

盖珂瑜,龙勇,蒋本俊,等.主塔C60大体积混凝土配合比设计及性能研究[J].混凝土与水泥制品,2024(4):91-95. GE K Y,LONG Y,JIANG B J,et al.Mix proportion design and performance study of C60 mass concrete for main tower[J].China Concrete and Cement Products,2024(4):91-95.

摘   要：制备了不同细度（674、810、1 126 m2/kg）的超细粉煤灰，研究了其掺量（0~25%）对水泥-超细粉煤灰胶凝材料性能的影响，分析了掺不同细度超细粉煤灰混凝土的工作性、力学性能和耐久性能。结果表明：超细粉煤灰的强度活性指数和需水量比均随着其细度的增加而增大；用0~25%的超细粉煤灰替代P·O 42.5级水泥后，胶凝材料的初凝、终凝时间分别延长了11~71 min、13~74 min；与未掺超细粉煤灰的混凝土相比，掺超细粉煤灰混凝土的坍落度提高，3 d和7 d抗压强度相差不大，28、56、90 d抗压强度均有所提高，抗碳化性能和抗硫酸盐侵蚀性能均有所提升。 Abstract: Ultrafine fly ash with different fineness (674, 810, 1 126 m2/kg) was prepared, and the effects of its content (0~25%) on the properties of cement-ultrafine fly ash cementitious materials was studied. The workability, mechanical properties, and durability of concrete with different fineness ultrafine fly ash were analyzed. The results show that the strength activity index and water demand ratio of ultrafine fly ash increase with the increase of the fineness. After replacing P·O 42.5 cement with 0~25% content of ultrafine fly ash, the initial setting time and final setting time of the cementitious materials are extended by 11~71 min and 13~74 min, respectively. Compared with the concrete without ultrafine fly ash, the slump of concrete with ultrafine fly ash is increased, the 3 d and 28 d compressive strength are not significantly different, the 28 d, 56 d, and 90 d compressive strength are increased, and the carbonation resistance and sulfate corrosion resistance are improved.

王玉斌,尹韶宁,潘栋,等.超细粉煤灰特性及其在混凝土中的应用研究[J].混凝土与水泥制品,2024(4):96-100. WANG Y B,YIN S N,PAN D,et al.Study on characteristics of ultrafine fly ash and its application in concrete[J].China Concrete and Cement Products,2024(4):96-100.

摘   要：采用基于电磁感应原理的无损检测方法，研究了混凝土中钢纤维的体积掺量（0~1.85%）、钢筋的直径（6~20 mm）、间距（100 mm、200 mm）和保护层厚度（20 mm、40 mm）与电磁信号值的关系。结果表明：随着钢纤维体积掺量的增加，电磁信号值增大；随着钢筋直径的增加，电磁信号值基本呈增大趋势；钢筋的间距和保护层厚度越大，电磁信号值越小；钢筋钢纤维混凝土的电磁信号值由钢纤维与钢筋产生的电磁信号值叠加而成；当钢筋间距大于100 mm时，相邻钢筋之间的电磁信号基本无影响；根据电磁信号波谷均值可检验和评定钢筋钢纤维混凝土中的钢纤维体积掺量是否合格；根据曲线的峰值和峰值出现位置可检验钢筋直径和钢筋所在位置是否合格。 Abstract: Using a non-destructive testing method based on the electromagnetic induction principle, the relationship between the volume content (0~1.85%) of steel fiber in concrete, the diameter (6~20 mm), spacing (100 mm, 200 mm), and protective layer thickness(20 mm, 40 mm) of steel bar with electromagnetic signal values was studied. The results show that as the volume content of steel fiber increases, the electromagnetic signal value increases. As the diameter of steel bar increases, the electromagnetic signal value generally shows an increasing trend. The larger the spacing and the protective layer thickness, the smaller the electromagnetic signal value. The electromagnetic signal value of steel reinforced concrete with steel fiber is formed by the superposition of the electromagnetic signal values generated by the steel fiber and the steel bar. When the spacing between steel bars is greater than 100 mm, the electromagnetic signal between adjacent steel bars has little effect. According to the mean valley value of electromagnetic signals, it is possible to test and evaluate whether the volume content of steel fiber in steel reinforced concrete with steel fiber is qualified. The diameter and the location of steel bar can be checked for compliance based on the peak value and the position of peak value of the curve.

叶芳,赵鹏,施俊航,等.基于电磁感应原理的钢筋钢纤维混凝土无损检测方法研究[J].混凝土与水泥制品,2024(4):77-81. YE Fang, ZHAO Peng, SHI Junhang,et al.Study on non-destructive testing method of steel reinforced concrete with steel fiber based on electromagnetic induction principle[J].China Concrete and Cement Products,2024(4):77-81.

摘   要：制作了5组不同再生粗骨料取代率（0、25%、50%、75%、100%）的试件，测试了其轴心抗压强度、弹性模量及破坏前后的声学参数，分析了再生粗骨料取代率、力学指标与声学参数之间的关系。结果表明：随着再生粗骨料取代率的增加，试件的轴心抗压强度呈先波动上升后下降的趋势，弹性模量呈下降趋势；在试件破坏前，试件的首波声速、首波幅值和主频值的数据离散性较小；在试件破坏后，各项声学参数较破坏前均下降，且数据离散性变大；首波声速和均方根振幅与弹性模量的相关性较好。 Abstract: Five sets of specimens with different replacement rates of recycled coarse aggregates (0, 25%, 50%, 75%, 100%) were made, and their axial compressive strength, elastic modulus, and acoustic parameters before and after failure were tested. The relationships between the replacement rate of recycled coarse aggregates, mechanical indicators, and acoustic parameters were analyzed. The results show that as the replacement rate of recycled coarse aggregate increases, the axial compressive strength of the specimens shows a fluctuating upward trend and then a decreasing trend, while the elastic modulus shows a decreasing trend. Before the failure of the specimen, the data discreteness of the head wave sound velocity, head wave amplitude, and dominant frequency value of the specimen is relatively small. After the failure of the specimen, all acoustic parameters decrease compared to before the failure, and the data discreteness increases. The correlation between the head wave sound velocity and root mean square amplitude have a good correlation with the elastic modulus.

郭广,周理,王帮康.基于超声检测的再生混凝土声学参数研究[J].混凝土与水泥制品,2024(4):82-86. GUO G,ZHOU L,WANG B K.Study on acoustic parameters of recycled concrete based on ultrasonic testing[J].China Concrete and Cement Products,2024(4):82-86.

摘   要：总结了国内外钢筋混凝土开洞梁的受力机理、受力性能、洞口补强加固方式、承载能力计算等研究现状。现有研究结果表明：洞口上、下弦杆可看作是偏心受压和偏心受拉状态；当洞口尺寸较小时，钢筋混凝土开洞梁可看作带有斜压腹杆的桁架模型，当洞口尺寸较大时，洞口部分为无斜压腹杆的平行弦杆以及无洞口部分的带有斜压腹杆的桁架模型；钢筋混凝土开洞梁主要有孔侧破坏和孔间破坏两种破坏模式；钢筋混凝土开洞梁的结构响应主要取决于荷载路径的中断程度；随着洞口高度和宽度的增加，钢筋混凝土开洞梁的承载力会降低，但若设计合理，不会形成薄弱区；普通钢筋、纤维布和纤维板都可用于洞口区域的加固，相应的抗剪承载力计算也较为完善。 Abstract: Based on the literature at home and abroad, the research status of reinforced concrete beams with openings in terms of mechanical mechanism, mechanical performance, reinforcement methods of openings, and calculation of bearing capacity are summarized. The existing research results show that the upper chord and the lower chord in the openings can be regarded as eccentric compression and eccentric tension, respectively. When the size of the openings is small, the reinforced concrete beams with openings can be regarded as a truss model with diagonal web members, and when the size of the openings is large, the reinforced concrete beams with openings can be regarded as parallel chords without diagonal web members at the openings and truss model with diagonal web members at the no-openings. There are two main failure modes of reinforced concrete beams with openings, namely, opening side failure and inter-opening failure. The structural response of reinforced concrete beams with openings mainly depends on the interruption degree of load path. With the increase of the height and width of the openings, the bearing capacity of reinforced concrete beams with openings decreases, and if the design is reasonable, weak areas can not be formed. Ordinary steel bars, fiber cloth, and fiber plate can be used to strengthen the opening area, and the corresponding calculation of shear bearing capacity is also relatively perfect. The research results can provide a reference for the popularization and application of reinforced concrete beams with openings.

张扬,颜阳,熊学玉,等.钢筋混凝土开洞梁力学性能研究现状与进展[J].混凝土与水泥制品,2024(4):63-69,76. ZHANG Y,YAN Y,XIONG X Y,et al.Research status and progress of mechanical properties of reinforced concrete beams with openings[J].China Concrete and Cement Products,2024(4):63-69,76.