摘   要：用石灰石粉部分取代水泥制备了再生混凝土（LP-RAC），并基于生命周期评价（LCA）方法，通过计算LP-RAC全生命周期（生产阶段、使用阶段、废弃阶段）产生的9种污染气体量（CO2、CO、NOx、SO2、CH4、N2O、NH3、PM10、NMVOC）及其对6种环境影响类型[气候变化潜值（GWP）、环境酸化潜值（AP）、非生物资源消耗潜值（ADP）、富营养化潜值（EP）、可吸入无机物（RI）、光化学臭氧合成潜值（POFP）]的“贡献率”，评价了LP-RAC全生命周期的环境影响。结果表明：LP-RAC的生产阶段对6种环境影响类型的“贡献率”均最大；在LP-RAC的生产阶段，水泥生产环节对GWP和RI的“贡献率”最大，直接排放环节对AP、EP和POFP的“贡献率”最大，河砂开采环节对ADP的“贡献率”最大。 Abstract: The recycled concrete(LP-RAC) was prepared by replacing some cement with limestone powder. Based on the life cycle assessment(LCA) method, the environmental impact of the whole life cycle(production stage, utilization stage, disposal stage) of LP-RAC was evaluated by calculating the amount of 9 types of polluting gases (CO2、CO、NOx、SO2、CH4、N2O、NH3、PM10、NMVOC) and their "contribution rate" to 6 types of environmental impact [global warming potential(GWP), acidification potential(AP), abiotic depletion potential(ADP), eutrophication potential(EP), respirable inorganic material(RI), photochemical ozone formation potential(POFP)]. The results show that the production stage of LP-RAC has the highest "contribution rate" to the 6 types of environmental impact. In the production stage of LP-RAC, the cement production process has the highest "contribution rate" to GWP and RI, the direct emission process has the highest "contribution rate" to AP, EP and POFP, and the river sand mining process has the highest "contribution rate" to ADP.  

李刚,郭晓潞,佘安明.基于全生命周期评价的掺石灰石粉再生混凝土环境影响研究[J].混凝土与水泥制品,2023(12):79-82,88. LI G,GUO X L,SHE A M.Study on environmental impact of recycled concrete with limestone powder based on whole life cycle assessment[J].China Concrete and Cement Products,2023(12):79-82,88.

摘   要：研究了建筑垃圾（微粉、再生砂）和钢渣（粉、砂）单、双组分固废对建筑3D打印材料可打印性和力学性能的影响，并优选出了最佳配合比。结果表明：采用单组分固废较难实现固废的大掺量（＞50%）利用；与同条件下的单组分固废相比，双组分固废基建筑3D打印材料的可打印性得到一定改善，其中，当m钢渣砂∶m再生砂=1∶1、m钢渣粉∶m微粉=7∶3时，JS4组打印材料的可打印性和可建造性总体上显著优于其他组；与浇筑试件相比，打印试件Y、Z方向的抗折强度相差较小，但X、Y、Z方向的抗压强度明显较低。 Abstract: The effects of single and dual component solid waste from construction waste(micro powder, recycled sand) and steel slag (powder, sand) on the printability and mechanical properties of 3D printing materials for buildings were studied, and the optimal mix proportion was selected. The results show that using single component solid waste is more difficult to achieve a large content(>50%) of solid waste utilization. Compared with single component solid waste under the same conditions, the printability of dual component solid waste based 3D printing materials for buildings has been improved to some extent. Among them, when msteel slag sand : mrecycled sand =1:1 and msteel slag powder : mmicro powder =7:3, the printability and constructability of JS4 group are significantly better than those of other groups overall. Compared with poured specimens, the difference in flexural strength in the Y and Z directions of printed specimens is relatively small, but the compressive strength in the X, Y and Z directions is significantly lower.

刘成,张立力,曹鑫铖,等.固废基建筑3D打印材料的制备及性能研究[J].混凝土与水泥制品,2023(12):83-88. LIU C,ZHANG L L,CAO X C,et al.Study on preparation and performance of solid waste based 3D printing materials for buildings[J].China Concrete and Cement Products,2023(12):83-88.

摘   要：研究了不同环境温度（-5、-10、-15 ℃）下防冻剂对混凝土受冻临界强度的影响，分析了保温材料（毛毡）热阻对混凝土预养时间的影响，并建立了保温材料热阻和覆盖厚度分别与混凝土预养时间的关系模型。结果表明：掺入适量防冻剂有效降低了混凝土的受冻临界强度；在相同环境温度下，混凝土表面温度每升高10 ℃，预养时间减少12%~20%；在相同混凝土表面温度下，环境温度每升高5 ℃，预养时间减少10%~16%；保温材料热阻与混凝土预养时间符合Origin软件中的YldFert模型，且拟合精度较高；结合YldFert模型和保温材料热阻计算公式，可以得到不同环境温度下，保温材料覆盖厚度的计算方法。 Abstract: The effects of antifreeze on the critical strength in frost resistance of concrete at different environmental temperatures (-5, -10, -15 ℃) were studied, and the influence of thermal resistance of insulation materials(felt) on the pre-curing time of concrete was analyzed, and the relationship model between the thermal resistance and coverage thickness of insulation materials and the pre-curing time of concrete was established. The results show that adding an appropriate amount of antifreeze can effectively reduces the critical strength in frost resistance of concrete. Under the same environmental temperature, for every 10 ℃ increase in surface temperature of concrete, the pre-curing time decreases by 12% to 20%. Under the same surface temperature of concrete, for every 5 ℃ increase in environmental temperature, the pre-curing time decreases by 10% to 16%. The thermal resistance of insulation materials and the pre-curing time of concrete comply with the YldFert model in Origin software, and the fitting accuracy is high. By combining the YldFert model and the thermal resistance calculation formula of insulation materials, the calculation method for the coverage thickness of insulation materials under different environmental temperatures can be obtained.

陈旭,韩世界,李绍纯,等.负温环境下防冻剂和保温材料对混凝土受冻临界强度的影响[J].混凝土与水泥制品,2023(12):89-93. CHEN X,HAN S J,LI S C,et al.Effect of antifreeze and insulation materials on critical strength in frost resistance of concrete in negative temperature environment[J].China Concrete and Cement Products,2023(12):89-93.

摘   要：研究了全再生细骨料干混砂浆的抗冻性能和耐高温性能。抗冻试验结果表明：随着冻融循环次数的增加，试件表面脱落现象逐渐加重，质量损失率逐渐增大，抗压、抗折强度降低。高温试验结果表明：随着温度的升高，试件表面发白现象愈发明显，并出现细小裂纹、边缘脱落现象；随着温度的升高，试件的抗压强度先增大后减小，抗折强度基本呈降低趋势，质量损失率基本呈增大趋势；当温度大于400 ℃后，试件的质量大幅降低。 Abstract: The frost resistance and high temperature resistance of dry-mix mortar with fully recycled fine aggregate were studied. The results of frost resistance test indicate that as the number of freeze-thaw cycles increases, the surface detachment phenomenon of the specimen gradually intensifies, the mass loss rate gradually increases, and the compressive and flexural strength decreases. The results of high temperature test show that as the temperature increases, the surface of the specimen becomes more white, and there are small cracks and edge detachment phenomena. As the temperature increases, the compressive strength of the specimen first increases and then decreases, the flexural strength basically shows a decreasing trend, and the mass loss rate basically shows an increasing trend. When the temperature exceeds 400 ℃, the mass of the specimen significantly decreases.

崔李三,任吉,谭春雷,等.全再生细骨料干混砂浆抗冻及耐高温性能研究[J].混凝土与水泥制品,2023(12):94-96,100. CUI L S,REN J,TAN C L,et al.Study on frost resistance and high temperature resistance of dry-mix mortar with fully recycled fine aggregate[J].China Concrete and Cement Products,2023(12):94-96,100.

摘   要：研究了铜尾矿砂等质量替代0、30%、50%、70%、100%的机制砂对混凝土耐污水腐蚀性能的影响，并对其作用机理进行了分析。结果表明：随着铜尾矿砂掺量的增加，试件在污水环境中浸泡90 d后的质量损失率降低，抗压强度保留率先增大后减小；混凝土对铜尾矿砂中的重金属具有一定固结作用，可有效减少混凝土表面的微生物附着量，抑制微生物的繁殖代谢，减少生物酸的生成量，从而提高混凝土的耐污水腐蚀性能。 Abstract: The effects of replacing 0, 30%, 50%, 70% and 100% machine-made sand with copper tailings sand on the corrosion resistance of concrete to sewage were studied, and its mechanism of action was analyzed. The results show that with the increase of copper tailings sand content, the mass loss rate of the specimen after soaking in sewage environment for 90 d decreases, and the retention rate of compressive strength first increases and then decreases. Concrete has a certain consolidation effect on heavy metals in copper tailings sand, which can effectively reduce the adhesion of microorganisms on the surface of concrete, inhibit the reproduction and metabolism of microorganisms, and reduce the generation of biological acids, thereby improving the corrosion resistance of concrete to sewage.

杨雪超,樊伟,杜渊博,等.污水环境下铜尾矿砂对混凝土性能的影响[J].混凝土与水泥制品,2023(12):97-100. YANG X C,FAN W,DU Y B,et al.Effect of copper tailings sand on performance of concrete in sewage environment[J].China Concrete and Cement Products,2023(12):97-100.

摘   要：为研究蒸压加气混凝土板生产时料浆发气过程中钢筋位移变化量及变化趋势与发气状态之间的对应关系，通过时间-钢筋位移曲线定量表征料浆的发气状态，以期为发气和稠化过程的检测和控制提供参考。 Abstract： In order to study the corresponding relationship between the change of the displacement of the steel bar and the change trend of the gas evolution state during the production of the autoclaved aerated concrete slab, the gas evolution state of the slurry through the time-reinforcement displacement curve was quantitatively characterized, which can provide references for the detection and control of gas evolution and thickening processes.

刘涛,李军奇,华靖文.蒸压加气板混凝土料浆发气状态与钢筋位移的关系研究[J].混凝土与水泥制品,2023(12):70-72. LIU T,LI J Q,HUA J W.Research on the relationship between the gas evolution state of slurry for the autoclaved aerated concrete slab and the displacement of steel bars[J].China Concrete and Cement Products,2023(12):70-72.