摘 要：为研究铁尾矿颗粒形貌对砂浆尺寸稳定性的影响，利用光学显微镜观察了铁尾矿砂、天然河砂和普通机制砂的颗粒形貌并对其进行了定量描述，探索量化指标对砂浆尺寸稳定性的影响规律。试验结果表明，三种细骨料中，铁尾矿砂的针片状、非球形程度最高，其颗粒表面光滑但存在最多的尖锐棱角。在干燥环境下，细骨料较低的OR值和RK值将显著增加砂浆试件的收缩值。由于铁尾矿砂这两个指标最低，其砂浆试件的尺寸稳定性低于天然河砂和普通机制砂砂浆试件。不同粒级的铁尾矿砂所配制的砂浆试件尺寸稳定性试验证明，此时影响砂浆尺寸稳定性主要因素不是颗粒形貌，而是粒级范围，粒级范围越小，则铁尾矿砂浆试件的尺寸收缩越大。 Abstract: The influence of particle morphology for iron ore tailing on dimension stability of mortar was studied, particle morphology for iron tailings sand(IOT), nature river sand(NS) and manufactured sand(MS) was observed by optical microscope, influence rules of quantitative description and indicators on stability of mortar dimension is carried out. The results show that, The results show that IOT sand is flakiness, has greater degree of irregular shape and smoother surface, which exists the most sharper edges and corners in three kinds of fine aggregates. Under dry environment, lower OR value and RK value for fine aggregates will be increased obviously through shrinkage value. Dimension stability of mortar specimens is lower than that of NS specimens and MS specimens, because of lowest OR value and RK value. Experiment of dimension stability for mortar specimens is proved by prepared IOT with different grain size, the main effecting factors of dimension stability of mortar is grain rang, not particle morphology, demensional shrinkage of IOT mortar specimens becomes greater with smaller grain range.

摘 要：在水胶比相同的条件下，制备了纯水泥混凝土、分别掺加30%和40%钢铁渣粉A（矿渣∶钢渣=7∶3）的混凝土、分别掺加30%和40%钢铁渣粉B（矿渣∶钢渣=6∶4）的混凝土，并经蒸汽养护后，测定了不同蒸养混凝土的抗压强度、抗氯离子渗透性、抗碳化性和抗硫酸盐侵蚀性。结果表明，掺加钢铁渣粉能提高混凝土后期的抗压强度；掺加钢铁渣粉A的混凝土的抗压强度高于掺加钢铁渣粉B的混凝土的抗压强度；掺加钢铁渣粉能提高混凝土28d的抗氯离子渗透性，其中掺加40%钢铁渣粉A能明显提高混凝土90d的抗氯离子渗透性；掺加钢铁渣粉对混凝土的抗碳化性能影响很小；掺加钢铁渣粉能明显提高混凝土的抗硫酸盐侵蚀性。 Abstract: The pure cement concrete is prepared by 30% and 40% ground iron and steel slag A (GGBS: steel slag ratio is 7:3), and concretes with 30% and 40% ground iron and steel slag B (GGBS∶steel slag ratio is 6∶4) under the same water-to-binder ratio, the compressive strength, resistance to chloride ion penetration, anti-carbonation and anti-sulfate attack properties of steam-cured concretes were determined. The results show that, adding ground iron and steel slag can improve the late-age compressive strength of concrete, the compressive strength of concrete with ground iron and steel slag A is higher than that of the concrete with ground iron and steel slag B. The resistance to chloride ion penetration of concrete is improved by adding ground iron and steel slag at the age of 28 days. The resistance to chloride ion penetration of concrete is improved by adding 40% ground iron and steel slag A at the age of 90 days. The addition of ground iron and steel slag has little effects on the anti-carbonation properties of concretes, which can improve the anti-sulfate attack property of concrete with ground iron and steel slag.

摘 要：研究了钢渣粉掺量和养护方式对全固废混凝土抗压强度的影响，并通过SEM分析了掺钢渣胶凝材料水化产物微观形貌。研究结果表明，钢渣粉掺量对混凝土的抗压强度有较大影响，湿热养护能够有效激发钢渣的活性，提高胶凝材料早期强度。掺入20%钢渣粉，采用56℃湿热养护，可以制备出28d抗压强度达77.26MPa的混凝土。掺入钢渣粉对水化产物种类不会造成影响，在反应的中后期，体系中C-S-H凝胶和钙矾石的协同生成能够促进体系强度的增长。 Abstract: The effect of steel slag powder proportion and curing process on compressive strength of solid waste concrete was investigated. The microstructure of hydration products was analyzed by SEM. The results showed that, steel slag content has great influence on the compressive strength of concrete. Steam curing can effectively stimulate the activity of steel slag and improve the early strength of gelling material. Mixed with 20% steel slag, curing at 56℃, the compressive strength of the concrete can achieve 77.26MPa at 28d. The addition of steel slag power has no effect on the type of hydration, the coordinated growth of the ettringite and C-S-H gel is significant for the strength of system in the middle and late stage of the reaction.

摘 要：根据某高层建筑塔楼劲性柱实际尺寸，模拟浇筑两组C70高强高性能钢筋混凝土足尺柱，以检验混凝土配合比、工作性能及强度等参数是否满足实际施工要求；同时通过预埋传感器的方法对模拟混凝土柱进行了温度和变形的实时监测，为进一步研究C70高强混凝土在实际工程条件下的热学性能和变形性能提供技术依据。 Abstract: Based on actual sizes of soft type rigid column for a high-rise building tower, full-scale column for two groups of C70 high strength high proformance reinforced concrete is poured in order to test whether its working performance, mix proportion and strength can meet the requirements of constructions in the project. Meanwhile, real-time minitoring of concrete column for temperature and deformation is carried out by embedded sensors, which can obtain technical basis for the further study on thermal properties and mechanical properties of C70 high strength concrete in practical engineering conditions.

摘 要：分析了典型立式径向挤压成型装备的结构及其成型工艺原理，介绍了当前国产立式径向挤压装备成形混凝土管的常见缺陷及主要成因，指出了立式径向挤压制管机研发中的关键问题并探讨了其解决方法，最后展望了立式径向挤压制管机的发展方向。 Abstract：Vertical radial pipe extrusion process is the production of small diameter concrete and reinforced concrete pipes of the latest technology methods. The typical vertical radial extrusion equipment structure and forming process principles are analyzed. And the common defects and the main causes of concrete pipes produced using current domestic vertical radial extrusion molding equipment are introduced. In addition, the key issues of vertical radial pipe extrusion machine and their solutions are put forward. Finally, the development trend of the vertical radial pipe extrusion is prospected.

摘 要：通过不同原料配比制备了钒尾矿免烧砖，并对其进行了相关的力学性能测试。研究结果表明，当粗细尾矿以54∶16的比例混合后，钒尾矿和水泥在固体干料中的质量分数为80%、20%；水与固体干料的质量比，PC减水剂掺入量为14%、0.3%时，可以制得28d抗折强度达到6.8MPa，抗压强度达到20.3MPa的钒尾矿免烧砖，符合免烧砖MU20等级的要求，是本试验制备普通水泥掺杂钒尾矿免烧砖的最佳配合比。 Abstract：Vanadium tailings baking-free bricks were produced by using different ratio of raw materials and their relative mechanical characteristics were tested. The results showed that, when the coarse tailings and fine tailings was mixed with ratio of 54:16, the mass fraction of cement and vanadium tailings is 20%, 80% respectively, when the water-solid dry material ratio is 14% and water-PC water reducing agent is 0.3% respectively, the 28d flexural strength and compressive strength can reach 6.8MPa and 20.3MPa respectively.