摘要
为研究海水侵蚀作用下充填材料的服役性能,对试样进行单轴抗压强度和低场核磁测试,研究了质量分数为5%的SO_(4)^(2-)和质量分数为3.5%的Cl^(-)侵蚀下充填材料的变化规律,揭示不同侵蚀离子对石灰石尾矿基充填材料力学性能的影响。试验结果表明:Cl^(-)和SO_(4)^(2-)对石灰石尾矿基充填材料抗压强度具有提升作用,随着Cl^(-)和SO_(4)^(2-)质量分数的增加,充填材料孔径及孔隙率均呈现减小的趋势,结石体中少害孔的个数随着养护龄期的增加而逐渐增多,多害孔的个数减少。在侵蚀条件下SO_(4)^(2-)和Cl^(-)对充填材料中硅铝质组分的水化反应具有促进作用,C-S-A-H凝胶和N-C-S-A-H凝胶增多,生成的水化产物充填了孔隙,使结构更加密实;同时SO_(4)^(2-)可与水化产物C-S-A-H凝胶发生反应,生成钙矾石,充实孔隙,使孔隙率减小。研究成果对滨海岩溶充填工程服役性能评价具有一定指导作用。
In order to study the service performance of filling materials under the action of seawater erosion,the uniaxial compre ssive strength and low-field nuclear magnetic analysis tests were carried out on the samples.The changes law of backfill materials when mass fraction of SO_(4)^(2-) was 5%and mass fraction of Cl^(-) was 3.5%erosion were studied,and the action mechanism of different erosive ions on the physical performance of limestone tailings backfill reinforcement was revealed.The test results showed that Cl^(-) and SO_(4)^(2-) had an improvement effect on the compressive strength of limestone tailings backfilling materials.With the increase of mass fraction of Cl^(-) and SO_(4)^(2-),the pore size and porosity of the filling material showed a decreasing trend,and the number of less harmful pores in the stone body gradually increased and the number of more harmful pores decreased with the increase of the maintenance age.Under the condition of erosion,SO_(4)^(2-) and Cl^(-) could promote the hydration reaction of silicon-aluminum components in the filling materials.C-S-A-H gel and N-C-S-A-H gel increase,and the hydration products generated fill the pores,making the structure more dense.At the same time,SO_(4)^(2-) could react with the hydration product C-S-A-H gel to produce ettringite and enrich the pores,thus reducing the porosity.The research results had certain guiding significance for long-term service safety evaluation of filling materials in coastal karst.
作者
周勇
李召峰
左志武
王川
林春金
张新
姚望
ZHOU Yong;LI Zhaofeng;ZUO Zhiwu;WANG Chuan;LIN Chunjin;ZHANG Xin;YAO Wang(Shandong High Speed Group Co.,Ltd.,Jinan 250101,Shandong,China;Shangdong Hi-speed Company Limited,Jinan 250014,Shandong,China;Geotechnical and Structural Engineering Research Center,Shandong University,Jinan 250061,Shandong,China)
出处
《山东大学学报（工学版）》
CAS
CSCD
北大核心
2022年第1期103-110,共8页
Journal of Shandong University（Engineering Science）
基金
山东省自然科学基金重点资助项目(ZR2020KE006)
山东省重大科技创新工程资助项目(2020CXGC011405)
山东省重点研发计划资助项目(GG201809260007)
国家自然科学基金面上资助项目(52178338)。
关键词
滨海岩溶
石灰石尾矿基充填材料
离子侵蚀
力学性能
微观结构
coastal karst
limestone tailing based filling materials
ion erosion
mechanical properties
microstructure
