再生骨料强化方法研究进展  

Review on Enhancement Methods of Recycled Aggregate

作　　者：王雅思[1,2,3] 郑建岚 游帆[1,2,3] WANG Yasi;ZHENG Jianlan;YOU Fan(College of Civil Engineering,Fuzhou University,Fuzhou 350108,China;College of Engineering,Fujian Jiangxia University,Fuzhou 350108,China;Coordinative Innovation Center for Environmentally Friendly and Energy Saving HPC of Fujian Province,Fuzhou 350108,China)

机构地区：[1]福州大学土木工程学院,福州350108 [2]福建江夏学院工程学院,福州350108 [3]福建省环保节能型高性能混凝土协同创新中心,福州350108

出　　处：《材料导报》2021年第5期5053-5061,共9页Materials Reports

基　　金：国家自然科学基金联合基金重点支持项目(U1605242);福建省自然科学基金项目(2020J01941);福建江夏学院专题研究项目(JXZ2018010)。

摘　　要：再生骨料混凝土作为新型环保材料,满足节约资源和能源、减少环境污染以及可持续发展战略的要求,是绿色混凝土的主要研究方向和推广方向。再生骨料表面附着老水泥砂浆,表面粗糙、棱角多,并含有大量孔洞以及二次破碎过程产生的微裂纹,与天然骨料相比,再生骨料存在密度低、吸水率大、压碎指标大、坚固性差、离散性大等不足,且再生骨料与其表面附着砂浆间存在薄弱界面区,使再生骨料混凝土的性能受到影响、工程应用受到限制。因此,提高再生骨料性能是再生骨料混凝土研究中的关键问题之一。传统提高再生骨料混凝土性能的方法主要聚焦在混凝土拌和阶段,通过改善拌和方法、加入矿物掺合料、优化混凝土配合比设计,或通过优化再生骨料级配、降低再生骨料取代率,以弱化再生骨料对再生骨料混凝土性能的不利影响,但本质上并未改善再生骨料的缺陷。而对再生骨料进行强化处理可改善再生骨料的性能。现有再生骨料强化方法主要从再生骨料表面附着砂浆着手,通过物理、化学或生物方法去除老砂浆或增强老砂浆来提高再生骨料的性能,如机械研磨、火山灰质浆液浸泡、纳米材料改性、二氧化碳强化法等。此外,通过骨料重组法对再生骨料成分进行分类、重组,也可在一定程度上提高再生骨料性能,进而达到改善再生骨料混凝土性能的目的。本文总结了国内外已有再生骨料强化方法的研究进展,分别介绍了去除老砂浆、增强老砂浆、骨料重组三类再生骨料强化方法及其作用机理,总结分析了再生骨料强化方法的强化效果,提出进一步研究再生骨料强化的方向。Recycled aggregate concrete,as a new environmental protection material,meets the strategy of saving resources and energy,reducing environmental pollution and sustainable development.It is the main research and promotion direction of green concrete.The surface of recycled aggregate is adhered to old cement mortar,rough and angular,and contains a large number of holes and microcracks during secondary crushing.Compared with natural aggregate,recycled aggregate has some shortcomings,such as low density,high water absorption,large crushing index,poor firmness and large dispersion,and there is a weak interface between recycled aggregate and adhered mortar,which affect the performance of recycled aggregate concrete and restrict its application in practical engineering.So improving the performance of recycled aggregate is one of the key problems in the research of recycled aggregate concrete.The existing methods to improve the performance of recycled aggregate concrete mainly focus on the mixing method,adding mineral admixtures and optimizing the mix of concrete in the mixing stage,or by optimizing the gradation of recycled aggregate and reducing the replacement rate of recycled aggregate to reduce the adverse effect of recycled aggregate.However,the defect of recycled aggregate has not been substantially improved.The performance of recycled aggregate can be improved by enhancement treatments.The enhancement treatments mainly start with the mortar attached,and remove or enhance the old mortar by physical,chemical or biological methods,so as to enhance the performance of recycled aggregate,such as mechanical grinding,pre-soaking in pozzolanic solution,nanomaterial slurry,carbonation,et al.In addition,the component recombination method can also improve the performance of recycled aggregates,and thus improve the performance of recycled aggregate concrete.In this paper,the research progress and their mechanism of each recycled aggregate enhancing methods at home and abroad were summarized,the strengthening effect of enhancem

关 键 词：再生骨料 附着水泥砂浆 强化 

分 类 号：TU528[建筑科学—建筑技术科学]