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第五期
摘 要:黏土砖再生粗骨料生态混凝土的制备工艺、结构以及性能与普通混凝土不同,黏土砖粗骨料由于破碎过程中产生裂隙较多,其强度比天然骨料低,强化后的骨料性能可满足制造生态混凝土的需要。本文研究了设计目标孔隙率、水胶比、骨料粒径等均会对黏土砖再生粗骨料混凝土的强度产生影响,结果表明,设计目标孔隙率影响最大,骨料粒径影响最小,在25%以上孔隙率要求下,优化混凝土配合比设计,可配制出强度大于5 MPa且具有较好施工性能的黏土砖再生粗骨料生态混凝土。
Abstract: The preparation process, structure and performance of clay brick recycled coarse aggregate ecological concrete are different from normal concrete. The strength of coarse aggregate of clay brick is lower than that of natural aggregate because there are many cracks during the process of crushing. The reinforced aggregate property can meet the needs of making ecological concrete. The effect of design target porosity, water-binder ratio and aggregate size on the strength of recycled coarse aggregate concrete of clay brick is studied. The results show that the design target has the greatest influence on the porosity and the aggregate particle size has the least effect. Under the requirement of more than 25% porosity, the concrete mix ratio design is optimized. The recycled coarse aggregate ecological concrete with strength greater than 5 MPa and good construction performance can be prepared.
孙勇.黏土砖再生粗骨料生态混凝土制备及微观性能研究[J].混凝土与水泥制品,2019(5):97-100.
SUN Y.Study on Preparation and Microscopic Properties of Clay Brick Recycled Coarse Aggregate Ecological Concrete[J].China Concrete and Cement Products,2019(5):97-100.
朱晓云1,孙国卿2
摘 要:为了探究硫酸盐侵蚀作用下粉煤灰再生混凝土性能的变化,测试了材料配比对混凝土抗压耐蚀系数和质量损失率的影响,得到合理的材料组成,并通过SEM观察再生混凝土中老骨料-新浆体、老浆体-新浆体和老骨料-老浆体三种界面过渡区的微观形貌,解释了粉煤灰对再生混凝土抗硫酸盐侵蚀的改善机理。结果显示,增大水胶比和再生骨料替代率都会削弱混凝土的抗硫酸盐侵蚀性能,而粉煤灰的掺入能明显提高混凝土的抗硫酸盐侵蚀能力。最终确定的水胶比为0.55,再生骨料替代率和粉煤灰掺量分别为50%和30%。老骨料-新浆体界面和老骨料-老浆体界面是粉煤灰再生混凝土中的双重薄弱面,在制备时需重点处理。
Abstract: In order to investigate the change of the performance of fly ash recycled concrete under the action of sulfate erosion, the effects of material ratio on the corrosion resistance coefficient and quality loss rate of concrete were tested and reasonable material composition was obtained. The microstructures of three interfacial transition zones of old aggregate-new slurry, old slurry-new slurry and old aggregate-old slurry in recycled concrete were observed by SEM. The results show that increasing the W/B and the replacement rate of recycled aggregate will weaken the sulfate corrosion resistance of concrete, but the addition of fly ash can obviously improve the performance of concrete against sulfate erosion. The W/B, the substitution rate of recycled aggregate and the amount of fly ash were determined by 0.55, 50% and 30 % respectively. The interface between old aggregate and new slurry, old aggregate and old slurry is the double weak surface in fly ash recycled concrete, so it should emphasis on preparation.
朱晓云,孙国卿.粉煤灰对再生混凝土抗硫酸盐侵蚀及界面过渡区微观特性的影响[J].混凝土与水泥制品,2019(5):92-96.
ZHU X Y,SUN G Q.The Influence of Fly Ash on Resistance to Sulphate Erosion and the Microstructure of Interfacial Transition Zone of Recycled Concrete[J].China Concrete and Cement Products,2019(5):92-96.
张智慧1,代清冬2
摘 要:将钢渣粉取代部分煅烧MgO,研究了不同掺量钢渣粉对磷酸镁水泥(MPC)混凝土力学性能和耐久性能的影响。试验结果表明,掺有5%~30%取代率的钢渣粉会降低MPC混凝土的早期强度,但会明显提高MPC混凝土的后期强度,当钢渣粉取代率为15%时,MPC混凝土的60 d抗压强度达到最大;较低和较高的钢渣粉取代率会对MPC混凝土的劈裂抗拉强度产生不利影响,当钢渣粉取代率为15%和20%时,MPC混凝土的抗拉强度高于基准组;不同钢渣粉取代率的MPC混凝土的耐水性能均高于基准组,当钢渣粉取代率超过10%后,MPC混凝土的强度保持率均在0.9以上;钢渣粉的掺入可在一定程度上提高MPC混凝土抗氯盐及硫酸盐侵蚀性能,但较高的钢渣粉取代率会对MPC混凝土抗硫酸盐侵蚀能力产生不利影响。
Abstract: The effect of steel slag powder on mechanical properties and durability of magnesium phosphate cement (MPC) concrete was investigated by partially substituting calcined MgO with steel slag powder. The results indicate that when adding steel slag powder with 5%~30% substitution ratios, the early strength of MPC concrete can be reduced, whereas the later strength of MPC concrete can be evidently enhanced. Specifically, the substitution ratio of steel slag powder is 15%, the 60 d compressive strength of MPC concrete reaches the maximum value. Lower and higher substitution ratio of steel slag powder will adversely affect the splitting tensile strength of MPC concrete, when the substitution ratios are 15% and 20%, the tensile strengths of MPC concrete are higher than those of reference group. The water resistance of MPC concrete with different substitution ratios of steel slag powder is higher than that of reference group. When the substitution ratio exceeds 10%, the strength retention rate of MPC concrete is above 0.9. The addition of steel slag powder can improve the corrosion resistance of MPC concrete to chloride and sulfate to some extent. However, the higher substitution rate of steel slag powder will have a negative influence on the sulfate corrosion resistance of MPC concrete.
张智慧,代清冬.钢渣粉部分替代煅烧MgO对MPC混凝土性能的影响[J].混凝土与水泥制品,2019(5):87-91.
ZHANG Z H,DAI Q D.Effects of Steel Slag Powder Partially Replaced Calcined MgO on Performance of MPC Concrete[J].China Concrete and Cement Products,2019(5):87-91.
苏永波,单贺明,侯 纲
摘 要:被动式超低能耗建筑是一种通过保温隔热性能和气密性能更高的围护结构,采用新风热回收技术,并利用可再生能源,提供舒适室内环境的建筑,可以满足现代人们的生活需要。本文以秦皇岛 “在水一方”项目为例,介绍了被动式超低能耗建筑外墙保温系统在施工中的具体措施,可为类似工程施工提供参考。
Abstract: Passive ultra-low energy consumption building can be constructed through a higher envelope of insulation and tightness. It can provide people with comfortable indoor living environment by adopting new wind and heat recovery technology and using renewable energy to meet the needs of modern people's lives. Taking the "water side" project in Qinhuangdao as an example, the concrete measures of passive exterior wall insulation system are introduced in construction of ultra-low energy consumption buildings, which can provide a reference for the construction of similar projects.
苏永波,单贺明,侯纲.被动式超低能耗建筑外墙保温系统施工措施分析[J].混凝土与水泥制品,2019(5):84-86.
SU Y B,SHAN H M,HOU G.Analysis of Construction Measures for External Wall Insulation System in Passive Ultra-low Energy Consumption Buildings[J].China Concrete and Cement Products,2019(5):84-86.
金奇志1,马 春1,刘元利2,劳 兵3
摘 要:为了研究清水混凝土在建筑工程中的应用效果,以广西某大学校门为例,从清水混凝土的材料配比、施工工艺及养护与修复等方面进行了系统分析和讨论,提出了清水混凝土在建筑立面设计中独特的装饰效果及施工要点,并阐述了所遇到的问题和改进方案,探索了清水混凝土的一些新制备思路和方法。
Abstract: In order to study the application effect of fair-faced concrete in architectural engineering, taking a university gate in Guangxi as an example, the material proportion, construction technology, maintenance and repair of fair-faced concrete are systematically analyzed and discussed, the unique decorative effect and construction points of fair-faced concrete in architectural design are put forward, and the main points are expound. The problems encountered and the improvement schemes are attempted to explore some new preparation ideas and methods of fair-faced concrete.
金奇志,马春,刘元利,等.清水混凝土建筑立面设计及工程应用[J].混凝土与水泥制品,2019(5):80-83.
JIN Q Z,MA C,LIU Y L,et al.Building Facade Design and Engineering Application of Fair-faced Concrete[J].China Concrete and Cement Products,2019(5):80-83.
王 军1,吴媛媛2,曾 维3,冷 政3
摘 要:混凝土作为用途最为广泛的建筑材料,其质量与建筑物结构安全关系重大,科学合理的测试方法是准确表征及评价硬化混凝土性能的基础,因此,国内外对硬化混凝土的性能测试均制定了相应的标准。本文从试件与试模、试件的制作和养护、抗压强度、试验机规范、抗折强度、劈裂抗拉强度、密度以及压力渗水深度等方面对比研究了欧洲与我国硬化混凝土性能测试方法标准之间的异同,可为我国标准的改进和修订提供借鉴。
Abstract: Concrete is the most widely used building material, and its quality is very important to the structural safety of buildings. A scientific and reasonable test method is the basis for accurately characterizing and evaluating the properties of hardened concrete. Therefore, domestic and international standards for the performance testing of hardened concrete have been formulated. In favor of the continuous improvement of China's standards and provide useful data and information for standard revision work, the similarities and differences between the standard of performance testing methods for hardened concrete in Europe and China are compared from the aspects of specimen preparation, trial manufacture, specimen fabrication and maintenance, compressive strength, test machine specification, flexural strength, splitting tensile strength, density and pressure seepage depth,which can provide a reference for the development of the standard.
王军,吴媛媛,曾维,等.国内外硬化混凝土性能测试方法标准对比研究[J].混凝土与水泥制品,2019(5):74-79.
WANG J,WU Y Y,ZENG W,et al.Comparative Research on Domestic and International Standards of Testing Methods of Hardened Concrete Performance[J].China Concrete and Cement Products,2019(5):74-79.