摘要
研究了3种尾矿砂(锡尾矿砂、硫铁尾矿砂和锂尾矿砂)取代河砂对盾构注浆料工作性、稳定性和力学性能的影响,探究了注浆料在早强剂作用下性能的变化规律,采用SEM分析了微观机理。研究表明,尾矿砂使盾构注浆料流动度和稠度减小,凝结时间缩短,泌水率减小,结石率增大,稳定性提高;相比使用天然河砂,使用锡尾矿砂、硫铁尾矿砂、锂尾矿砂时盾构注浆料的28 d抗压强度分别提高了14.62%、0.84%、-25.21%;掺早强剂时注浆料的3 d抗压强度分别提高了52.78%、55.56%、28.33%。盾构注浆料水化产物主要为水化硅酸钙凝胶和少量针状钙矾石;硫铝酸盐类早强剂的掺入可进一步减少孔隙,增加钙矾石生成量,提高早期强度。
The effects of three types of tailings sand(tin,pyrite,and lithium)replacing river sand on the workability,stability,and mechanical properties of shield grouting materials were studied.The change law in the performance of tailings-based grouting materials under the influence of early strength agents was investigated and the the microscopic mechanism was analyzed by SEM.Research has shown that tailings sand reduces the fluidity,consistency,and setting time of shield grouting materials,lowers its workability,reduces its bleeding rate,increases its stone formation rate,and improves its stability.Compared with natural river sand,the 28 day compressive strength of shield grouting materials using tin tailings sand,pyrite tailings sand,and lithium tailings sand increased by 14.62%,0.84%,and-25.21%,respectively.Compared to natural river sand,when using tin tailings sand,sulfur iron tailings sand,and lithium tailings sand,the 3-day compressive strength of grouting materials with early strength agent increased by 52.78%,55.56%,and 28.33%,respectively.The hydration products of shield grouting materials are mainly hydrated calcium silicate gel and a small amount of needle like ettringite.The incorporation of sulfoaluminate early strength agents can further reduce pores,increase the formation of ettringite,and improve early strength.
作者
郭泓婕
邱文俊
舒本安
杨腾宇
GUO Hongjie;QIU Wenjun;SHU Ben'an;YANG Tengyu(The Hong Kong Polytechnic University,Kowloon 999077,China;Foshan Transportation Science and Technology Co.Ltd.,Foshan 528000,China)
出处
《新型建筑材料》
2024年第9期10-14,共5页
New Building Materials
基金
湖北工业大学河湖智慧健康感知与生态修复教育部重点实验室开放研究基金(HGKFYBP20)
长沙理工大学公路养护技术国家工程研究中心开放基金资助项目(kfj230202)。
关键词
尾矿砂
盾构注浆料
早强剂
强度
tailings sand
shield grouting material
early strength agents
strength
