不同高厚比复合墙体在水平荷载作用下的实验研究

以现浇金属尾矿泡沫混凝土复合墙体为研究对象,共设计制作3组不同高厚比墙体试件,完成各墙体试件在水平荷载作用下的试验,水平荷载作用方向为平面外垂直于墙体,分析了各实验墙体的破坏形态、破坏特征等,研究了水平荷载作用下实验墙体的极限承载力、极限位移、荷载-龙骨应变曲线、荷载-位移曲线。

金属尾矿渣大量利用的适用技术

利用金属尾矿——铅锌渣生产建筑材料,是大力发展循环经济、提高资源利用率,解决当前我国资源、环境对经济发展制约的有效、适用途径之一。通过试验、分析、研究、比较认为,利用铅锌渣生产混凝土多孔砖,是金属尾矿渣大量利用的最佳方案,也为金属尾矿的综合利用提供了一种适用、有效的解决方案。

Seismic assessment of RC frames infilled with innovative CFS walls considering seismic orientation effect

The metal tailings porous concrete cold-formed steel(MCFS)wall is an innovative cold-formed steel(CFS)wall with good thermal and mechanical properties,which has the potential to be widely utilized as the infilled wall(IW).In this paper,the MCFS walls are adopted in the reinforced concrete(RC)frame,and the seismic performance of the building subjected to ground motions with various incidence angles are investigated.Three-dimensional finite element model of the studied building is developed with full consideration of the in-plain(IP)and out-of-plane(OP)behavior of MCFS walls.Incremental dynamic analysis is conducted to obtain the deformation responses of frames and damage ratios of MCFS walls under the combined effect of seismic intensity and orientation.Fragility curves are generated to assess the seismic performance of the building and investigate the effect of ground motion orientation.The results validate the superior performance of infilled MCFS walls,and reveal that the seismic orientation has a considerable impact on the response along each reference axis of the structure.Furthermore,different incidence angles induce up to 10.2%and 14.4%variations in the median Sa(T1)of fragilities for the frames in X and Y axes,and the corresponding change rates in the median Sa(T1)for the walls are 13.5%and 15.1%,respectively.However,for the overall performance of the building,the seismic orientation effect is less significant.The rates of changes in median Sa(T1)are less than 4%for both frames and MCFS walls.

铁尾矿加气混凝土的制备和性能

以铁尾矿为主要原料制备加气混凝土,研究了铁尾矿的细度和掺量对其性能的影响。结果表明:随着铁尾矿细度的减小料浆的流动性提高,大量气孔的形成使制品的绝干密度降低;但是,细度过小使料浆的流动性降低,在浇注过程中大量气孔的破裂使制品的绝干密度提高。铁尾矿细度减小可提高水化反应速度,生成更多的水化产物,使制品的抗压强度提高。但是,铁尾矿过细使未反应的原料残核过分细小,不能形成良好的气孔结构,导致其抗压强度降低。提高铁尾矿的掺量能使水化产物之间的空隙充分填充,制品的绝干密度随之提高。铁尾矿掺量的提高使托贝莫来石的数量增加,由针片状变为短纤维状,相互交叉形成了网状结构,使制品的抗压强度提高;但是铁尾矿掺量过高使结晶良好的托贝莫来石数量减少,网状结构变得相对松散,导致制品的抗压强度降低。

铜尾矿改性机制砂C50混凝土的制备研究

利用铜尾矿改性机制砂制备混凝土不仅可改进混凝土性能,同时还可充分消纳铜尾矿固体废弃物。试验对比铜尾矿改性机制砂C50混凝土与机制砂、河砂-机制砂混合砂、河砂C50混凝土的性能。结果表明,铜尾矿改性机制砂可提升C50混凝土长龄期强度发展与均质性,干缩率虽略有提升但不足以导致显著的应用性能缺陷。压汞法测试结果显示铜尾矿改性机制砂虽导致混凝土孔隙率略微上升,但其孔径总体趋于细化,形成了更为理想的孔结构。混凝土对铜尾矿中重金属离子具有显著的固化效果,可消除其环境危害性。利用铜尾矿改性机制砂制备混凝土具有广阔的应用前景。