采用钢渣与废玻璃混凝土的钢管混凝土柱静力和滞回性能研究

In recent years, there has been a growing emphasis on the utilisation of waste materials namely steel slag and waste glass as aggregates in concrete. However, the volumetric instability (expansion) of concrete made with steel slag and waste glass limits the application of those concrete in engineering practice. Instead, a small amount of concrete expansion (if any) will be beneficial to maintain the interaction between the steel tube and concrete if this concrete applied in concrete-filled steel tubular (CFST) columns. Till now, no research has been conducted on this topic. Therefore, this project is planned to investigate the effect of concrete made with steel slag and waste glass on the stiffness, load carrying capacity, ductility and capacity of energy dissipation of CFST columns under static and dynamic load. And the feasibility of current design guideline on prediction of CFST columns employing these concretes is also studied. The behaviour of CFST column infilled steel slag and waste glass concrete will be compared with those filled with normal concrete through experimental investigation, coupling with the mechanism and parameter analysis by using numerical analysis method. Simplified calculation method for CFST columns employing concrete made with steel slag and waste glass under axial loading, eccentric loading and pure bending, as well as the practical prediction methods to load bearing capacity under static load and practical restoring force model under dynamic load, will be proposed finally. It is expected to provide scientific evidence to fulfil current design guideline and reference for engineering practice in future.

近年来,着力于利用钢渣与废玻璃这类废弃料为混凝土骨料的研究不断增多。但是钢渣与废玻璃混凝土的体积不稳定性(膨胀)却制约了其工程应用前景。若将其运用到钢管混凝土柱中，少量的混凝土膨胀却有利于保持钢管与混凝土之间的相互作用。鉴于至今尚未见相关研究报道，本项目拟针对钢渣与废玻璃混凝土在单调和滞回荷载作用下钢管混凝土柱刚度、承载力、延性和耗能能力的影响规律，及现有设计规范对采用此类混凝土的钢管混凝土构件适用性等关键科学问题展开研究。通过试验研究，比较分析钢渣与废玻璃混凝土和普通混凝土在钢管混凝土构件中的性能，并配合数值模拟进行机理分析和参数分析。最终建立采用钢渣与废玻璃混凝土的构件轴压、偏压及纯弯承载力计算方法和往复荷载作用下的实用恢复力模型。为现有设计规范的完善和工程设计提供科学依据。

近年来开始重视固体废弃物在建筑材料中的利用。这不仅有助于降低对自然资源的依赖，还可减少相应的垃圾填埋成本，保护环境免受可能的污染。通过创造性的利用固体废弃物（不锈钢渣和废玻璃）作为骨料或胶凝材料制备混凝土并将其运用到钢管混凝土结构中，不仅可以利用外钢管约束住混凝土的体积不稳定性（膨胀），还可以某种程度上提高钢管混凝土的约束效应。本项目研究 “采用钢渣与废玻璃混凝土的钢管混凝土构件在静力（轴压、纯弯和偏压）和往复荷载作用下 (滞回) 的力学性能。具体进行了以下几个方面的研究：.首先选取各类不锈钢废渣与各色废玻璃，以单一替代到综合替代的思路研究不锈钢渣与废玻璃作为混凝土中胶凝材料与粗细骨料替代的可行性，并优化其替代率和综合替代方式，研究发现未经陈伏的不锈钢渣粗骨料可导致混凝土产生严重的体积不安定性；随后分析共七类替代方式的不锈钢渣与废玻璃混凝土对新型不锈钢管混凝土轴压短柱极限承载力、约束效应和延性的影响规律，研究结果证明混凝土的体积膨胀可以提高钢管混凝土的约束效应；接着在轴压短柱试验的基础上优化两类不锈钢渣与废玻璃混凝土配合比，分析其在新型不锈钢管混凝土纯弯和压弯试件的力学性能。随后运用ABAQUS软件对轴压、纯弯和压弯试验结果进行模拟分析以验证有限元的适用性，并基于验证的有限元模型对构件的N-M相关曲线进行参数分析并修正相关实用计算方法；最后展开相关滞回性能试验，并结合有限元分析及参数计算，提出适用于内填不锈钢渣与废玻璃混凝土的钢管混凝土构件的实用恢复力模型。