秸秆纤维增强镁渣固化锂渣力学性能与微观特征研究  

Investigate on mechanical properties and microscopic characteristics of solidified lithium slag with magnesium slag reinforced by straw fiber

作　　者：郭乔明 陈峰 赵华 杨璐 陈慧 温久然[3] GUO Qiaoming;CHEN Feng;ZHAO Hua;YANG Lu;CHEN Hui;WEN Jiuran(Jiangxi Communications Investment Group Co.,Ltd.,Nanchang 330199,China;School of Infrastructure Engineering,Nanchang University,Nanchang 330131,China;School of Material Science and Engineering,Chang′an University,Xi′an 710064,China)

机构地区：[1]江西省交通投资集团有限责任公司,江西南昌330199 [2]南昌大学工程建设学院,江西南昌330031 [3]长安大学材料科学与工程学院,陕西西安710064

出　　处：《混凝土》2025年第3期128-132,共5页Concrete

基　　金：江西省重点工程科技项目(2023C0014)。

摘　　要：为有效解决海量锂渣、镁渣等大宗工业固废限制新能源及冶金行业发展的问题,实现锂渣、镁渣等固废在道路工程中的资源化.以镁渣作为主固化剂,采用秸秆纤维加筋的方法对锂渣进行固化处理并制备了适用于路面基层的秸秆纤维增强镁渣-锂渣复合固化材料(MS-LS).通过无侧限抗压强度测试研究了MS-LS的力学性能,结合XRD与SEM试验探究了MS-LS的微观结构特征以及固化机理.结果表明:MS-LS的抗压强度随着纤维掺量的增加呈现先增后减的趋势.当秸秆纤维掺量为0.2%、纤维长度为250μm的抗压强度峰值达到了4.25 MPa,相较于830μm-0.1%组(1.436 MPa)提高了1.96倍;强度的显著增大主要归因于水化硅酸钙(C-S-H)凝胶对LS颗粒的胶结固化作用以及秸秆纤维加筋增强作用.颗粒嵌挤填充作用及石膏相水化硬化作用也促进了结构强度的形成与发展;在镁渣掺量为6%的条件下,秸秆纤维对于MS-LS的增强作用存在的最佳掺量为0.2%,最佳纤维长度为250μm。To effectively tackle the challenges associated with the low utilization rate of metallurgical solid waste,the large-scale application of bulk metallurgical solid waste in road base materials has been recognized as a significant research direction.In this study,magnesium slag was utilized as the primary curing agent,and a reinforcing method using straw fibers was applied to solidify lithium slag,resulting in the development of a straw fiber-reinforced magnesium slag-lithium slag composite curing material(MS-LS).The mechanical properties of MS-LS were assessed through unconfined compressive strength tests,while the microstructural characteristics and curing mechanisms were investigated using X-ray diffraction(XRD)and scanning electron microscopy(SEM).The results indicated that the compressive strength of MS-LS exhibited an initial increase followed by a subsequent decrease with the elevation of fiber content.A peak compressive strength of 4.25 MPa was attained at a straw fiber content of 0.2%and a fiber length of 250μm,representing a 1.96-fold enhancement when compared to the 830μm-0.1%group(1.436 MPa).This significant increase in strength was primarily attributed to the binding and curing effects of calcium silicate hydrate(C-S-H)gel on the lithium slag particles,in conjunction with the reinforcing action of the straw fibers.The interlocking and filling actions of the particles,as well as the hydration hardening effects of the gypsum phase,further facilitated the formation and development of structural strength.Under the condition of 6%magnesium slag content,the optimal straw fiber reinforcement was determined to be 0.2%,with the ideal fiber length being 250μm.

关 键 词：固废处置 秸秆纤维 抗压强度 微观分析 

分 类 号：TU528.041[建筑科学—建筑技术科学]