摘   要：对比研究了不同掺量的偏高岭土（0、10%、30%）对碱矿渣水泥在20~1 000 ℃高温作用下的外观形貌和抗压强度的影响，并进行了XRD、FT-IR和SEM分析。结果表明：当温度不大于400 ℃时，不同偏高岭土掺量试件的外观形貌和抗压强度均无明显变化；当温度升至600 ℃时，体系中的水化产物C-S-(A)-H凝胶脱水，试件内部结构出现微裂纹，抗压强度下降，但掺入适量偏高岭土能在一定程度上减少抗压强度损失；当温度达到1 000 ℃时，未掺偏高岭土试件的固相反应产物主要为钙黄长石晶体颗粒，且颗粒之间较为松散，微观结构密实度较低，而掺偏高岭土试件的固相反应产物主要为钠长石，微观结构呈空间网状，密实度较高，耐高温性能相对较好。 Abstract: A comparative study was conducted on the effects of different contents of metakaolin(0, 10%, 30%) on the appearance and compressive strength of alkali activated slag cement under high temperature conditions of 20~1 000 ℃, and XRD, FT-IR, and SEM analyses were conducted. The results show that when the temperature is not greater than 400 ℃, there is no significant change in the appearance and compressive strength of specimens with different metakaolin content. When the temperature rises to 600 ℃, the hydration product C-S-(A)-H gel in the system will be dehydrated, and the internal structure of the specimen will appear microcracks, reducing the compressive strength. However, the compressive strength loss can be reduced to a certain extent by adding appropriate content of metakaolin. When the temperature reaches 1 000 ℃, the solid reaction product of the specimen without metakaolin is mainly calcium feldspar crystal particles, and the particles are relatively loose with low microstructure density. On the other hand, the solid reaction product of the specimen with metakaolin is mainly sodium feldspar, with a spatial network structure, high density, and relatively good high temperature resistance.

吕淑莲,雷华,程臻赟.偏高岭土对碱矿渣水泥耐高温性能的影响[J].混凝土与水泥制品,2024(11):100-105. LYU S L,LEI H,CHENG Z Y.Effect of metakaolin on high temperature resistance of alkali activated slag cement[J].China Concrete and Cement Products,2024(11):100-105.

摘   要：采用沙漠砂和粗骨料复配大掺量替代石英砂制备了超高性能混凝土（UHPC），通过正交试验研究了水胶比（0.16、0.18、0.20）、沙漠砂掺量（20%、40%、60%）、钢纤维掺量（1%、2%、3%）和粗骨料掺量（10%、20%、30%）对UHPC流动性和抗压强度的影响，并与未掺沙漠砂和粗骨料的基准组进行了对比。结果表明：沙漠砂-粗骨料UHPC的最佳配合比组合为水胶比0.16、沙漠砂掺量40%、钢纤维掺量2%、粗骨料掺量20%，此时，UHPC试件的28 d抗压强度较基准组提高了5.8%，流动度较基准组降低了10.4%，但流动度仍满足相关规范要求。 Abstract: Ultra-high performance concrete(UHPC) was prepared by replacing quartz sand with a large amount of the combination of desert sand and coarse aggregates. The effects of water-cement ratio(0.16, 0.18, 0.20), desert sand content (20%, 40%, 60%), steel fiber content(1%, 2%, 3%), and coarse aggregate content(10%, 20%, 30%) on the flowability and compressive strength of UHPC were studied through orthogonal experiments, and compared with the reference group without desert sand and coarse aggregates. The results show that the optimal mix proportion combination of desert sand-coarse aggregate UHPC is the water-cement ratio of 0.16, desert sand content of 40%, steel fiber content of 2%, and coarse aggregate content of 20%. At this time, the 28 d compressive strength of UHPC specimens increases by 5.8% compared to the reference group, and the flowability decreases by 10.4% compared to the reference group, but the flowability still meets the requirements of relevant specifications.

马熙伦,罗永,沙东,等.沙漠砂-粗骨料UHPC配合比设计及性能研究[J].混凝土与水泥制品,2024(11):106-110. MA X L,LUO Y,SHA D,et al.Research on mix proportion design and performance of desert sand- coarse aggregate UHPC[J].China Concrete and Cement Products,2024(11):106-110.

摘   要：研究了再生微粉等质量取代0、5%、10%、15%、20%的水泥对再生混凝土抗压强度，劈裂抗拉强度和弹性模量的影响，并进行了XRD和SEM分析。结果表明：随着再生微粉掺量的增加，试件各龄期的抗压强度、劈裂抗拉强度和弹性模量基本呈先增大后减小的趋势，最佳掺量为15%；再生微粉具有一定的火山灰活性和填充效应，适量掺入可以有效改善再生混凝土的界面过渡区结构，使其更加致密。 Abstract: The effects of replacing 0, 5%, 10%, 15%, and 20% cement with recycled powder on the compressive strength, splitting tensile strength, and elastic modulus of recycled concrete were studied, and the XRD and SEM analysis were conducted. The results show that with the increase of the content of recycled powder, the compressive strength, splitting tensile strength, and elastic modulus of the specimens at each age show a trend of first increasing and then decreasing, and the optimal content is 15%. Recycled powder has certain volcanic ash activity and filling effect, and moderate addition can effectively improve the interface transition zone structure of recycled concrete, making it denser.

刘诚,白希选,王相卿.再生微粉对再生混凝土力学性能的影响[J].混凝土与水泥制品,2024(11):111-114,120. LIU C,BAI X X,WANG X Q.Effects of recycled powder on mechanical properties of recycled concrete[J].China Concrete and Cement Products,2024(11):111-114,120.

摘   要：从黏附砂浆、界面过渡区、裂纹损伤这3个方面介绍了建筑垃圾再生骨料（RCA）的特性，并分析了RCA对混凝土性能的影响。基于此，总结了近年来常见的建筑垃圾再生骨料改性方法，如酸化改性、化学浆液改性、纳米技术改性、碳化改性、微生物矿化改性、复合技术改性等，并分析了其改性机理，可为建筑垃圾资源化利用和再生骨料的性能提升研究提供参考。 Abstract: The characteristics of construction waste recycled aggregates(RCA) from the aspects of adhesive mortar, interface transition zone, and crack damage are introduced, and the influence of RCA on performance of concrete is analyzed. Based on this. The common modification methods of construction waste recycled aggregates in recent years are summarized, such as acidification modification, chemical slurry modification, nanotechnology modification, carbonization modification, microbial mineralization modification, composite technology modification, etc. The modification mechanism is analyzed, which can provide a reference for the resource utilization of construction waste and the performance improvement of recycled aggregates.

李克青,齐国强,曹芳菲,等.建筑垃圾再生骨料的特性及改性方法研究进展[J].混凝土与水泥制品,2024(11):115-12. LI K Q,QI G Q,CAO F F,et al.Research progress on characteristics and modification methods of construction waste recycled aggregates[J].China Concrete and Cement Products,2024(11):115-12.

万俊飞,罗喜.模具结构形式和振捣方式对清水混凝土外观质量和性能的影响[J].混凝土与水泥制品,2024(11):96-99,105. WAN J F,LUO X.Effects of mold structure form and vibration method on appearance quality and properties of fair-faced concrete[J].China Concrete and Cement Products,2024(11):96-99,105.

摘   要：通过与铺砂法对比，探究了双目视觉成像法在检测预制混凝土（PC）构件结合面粗糙度方面的可行性，分析了构件表面潮湿程度、光照强度和测试角度对双目视觉成像法检测结果的影响。结果表明：采用双目视觉成像法检测构件结合面粗糙度是可行的，能够满足工程检测需要；采用双目视觉成像法检测不受环境光照强度的影响，但需保证构件表面没有积水，且构件与测量镜头应保持水平，否则需对测试角度进行合理修正。 Abstract: By comparing with the sand laying method, the feasibility of binocular vision imaging method in detecting the roughness of the joint surface of precast concrete(PC) components was studied. The influence of surface moisture level, light intensity, and testing angle on the detection results of binocular vision imaging method was analyzed. The results show that using binocular vision imaging method to detect the roughness of the joint surface of components is feasible and can meet the needs of engineering inspection. The use of binocular vision imaging method for detection is not affected by the ambient light intensity, but it is necessary to ensure that there is no water accumulation on the surface of the component, and the component and the measuring lens should be kept horizontal. Otherwise, the testing angle needs to be reasonably corrected.

赵建华,凌良建,贾立军,等.双目视觉成像法检测PC构件表面粗糙度试验研究[J].混凝土与水泥制品,2024(11):80-84. ZHAO J H,LING L J,JIA L J,et al.Experimental study on detecting surface roughness of PC components using binocular vision imaging method[J].China Concrete and Cement Products,2024(11):80-84.