废弃混凝土再生微粉制备盾构注浆料及性能演变规律  

Preparation of Shield Grouting Material with Recycled Fine Powder from Waste Concrete and Its Performance Evolution

作　　者：郑圣飚 储玉婷 高鹏[1,2,3,4] 詹炳根[1,2,3,4] 王国陶 张青峰[6] 卢炳斗 ZHENG Shengbiao;CHU Yuting;GAO Peng;ZHAN Binggen;WANG Guotao;ZHANG Qingfeng;LU Bingdou(School of Civil and Hydraulic Engineering,Hefei University of Technology,Hefei 230009,China;Engineering Research Center of Low-Carbon Technology and Equipment for Cement-Based Materials,Ministry of Education,Hefei 230009,China;Anhui Engineering Research Center for Low-Carbon Technology of Cementitious Materials,Hefei 230009,China;Anhui Key Laboratory of Civil Engineering Structures and Materials,Hefei 230009,China;Hainan Hengbao Concrete Engineering Co.,Ltd.,Haikou 430048,China;Hefei University of Technology Design Institute(Group)Co.,Hefei 230009,China)

机构地区：[1]合肥工业大学土木与水利工程学院,合肥230009 [2]水泥基材料低碳技术与装备教育部工程研究中心,合肥230009 [3]安徽省水泥基材料低碳技术工程研究中心,合肥230009 [4]土木工程结构与材料安徽省重点实验室,合肥230009 [5]海南恒宝混凝土工程有限公司,海口430048 [6]合肥工业大学设计院(集团)有限公司,合肥230009

出　　处：《硅酸盐通报》2024年第12期4491-4500,共10页Bulletin of the Chinese Ceramic Society

基　　金：国家“十三·五”重点研发计划(2020YFC1909902);合肥工业大学设计院(集团)有限公司企业委托(W2023JSKF0404);中央高校基本科研业务费专项资金资助(JZ2023HGTB0256,PA2023GDSK0069)。

摘　　要：废弃混凝土解体产生的再生微粉(RFP)产量高,具有一定活性,有望部分替代水泥、粉煤灰和膨润土制备RFP盾构注浆料,然而RFP对盾构注浆料性能的影响规律尚不明确,难以实际应用。本文对RFP盾构注浆料的初始流动度、凝结时间、抗压强度和干燥收缩进行试验测定。结果表明:RFP替代水泥易造成浆体流变性能下降,当RFP替代水泥12.5%(质量分数,下同)时,盾构注浆料流动度为17.6 cm,不满足规范要求(21±3)cm;RFP替代膨润土易导致浆体工作性能降低,当RFP替代膨润土30%时,浆体泌水率为5.2%,且出现分层现象;RFP替代粉煤灰有利于提高浆体流动性能,当RFP替代粉煤灰30%时,浆体流动度增加16.5%,泌水率低,无分层现象。RFP“微集料”效应构筑刚性支撑骨架,能够降低浆体孔隙率,有效抑制干燥收缩。综合各方面性能,优选注浆料配比:水胶比0.31、胶砂比0.66、水泥27%、膨润土44.5%、粉煤灰9.4%、RFP 19.1%、减水剂0.3%。Recycled fine powder(RFP)produced by the disintegration of waste concrete has high yield and certain activity,which is expected to partially replace cement,fly ash and bentonite to prepare RFP shield grouting material.However,RFP influence on the performance of shield grouting material is not clear,which is difficult to guide engineering application.In this paper,the initial fluidity,setting time,compressive strength and drying shrinkage of RFP shield grouting material were tested.The results show that the RFP replacement of cement is easy to decrease the rheological properties of shield grouting material.When RFP replaces 12.5%(mass fraction,same below)cement,the fluidity of shield grouting material is 17.6 cm,which does not meet the specification requirements(21±3)cm.The replacement of bentonite by RFP results in the deterioration of slurry mance.When RFP replaces 30%bentonite,the shield grouting material bleeding rate is 5.2%,and the stratification phenomenon occurs.The replacement of fly ash by RFP is beneficial to improve the fluidity.When RFP replaces 30%fly ash,the fluidity of shield grouting material increases by 16.5%,the bleeding rate is low,and there is no stratification.The RFP‘micro-aggregate’effect builds a rigid support skeleton,which can reduce the porosity of shield grouting material and effectively inhibit drying shrinkage.Based on the performance of all aspects,the optimum slurry ratio is:water-binder ratio 0.31,cement-sand ratio 0.66,cement 27%,bentonite 44.5%,fly ash 9.4%,RFP 19.1%,water reducer 0.3%.

关 键 词：再生微粉 废弃混凝土 盾构注浆料 膨润土 干燥收缩 

分 类 号：TQ172.7[化学工程—水泥工业]