(1 北京科技大学土木与资源工程学院， 北京 100083； 2 河北省建筑科学研究院有限公司，石家庄 050021； 3 河北省固废建材化利用科学与技术重点实验室， 石家庄 050021)

摘要: 利用杭绍台高速公路隧道洞砟，制备凝灰岩型机制砂，分析了机制砂及石粉特性，研究其对砂浆、混凝土流动性与强度的影响，利用条形筛检测机制砂中片状颗粒，探究不同片状颗粒含量对砂浆与混凝土和易性的影响规律，并研究不同砂率对 C30 与 C35 混凝土性能的影响。 试验结果表明:凝灰岩型机制砂为硅质机制砂，表面的断键导致石粉易团聚，对亚甲蓝值不敏感，需水量大。 随着石粉与片状颗粒含量的增加，砂浆与混凝土的流动性与强度不断降低。 凝灰岩片状颗粒含量大于石灰岩片状颗粒含量对强度的影响程度，片状颗粒含量对低水胶比砂浆流动性及强度影响幅度大于高水胶比影响幅度。 考虑混凝土的工作性和抗压强度，机制砂中石粉含量宜小于 8%，片状颗粒含量宜小于 10%，选定 C30 的砂率为 43%，C35 的砂率为 41%。

关键词: 凝灰岩； 石灰岩； 机制砂； 和易性； 流动性； 石粉； 片状颗粒

中图分类号:TU525 文献标志码:A 文章编号:1002￣848X(2022)02￣0120￣07

DOI:10. 19701 / j.jzjg.LS201854

Study on workability and mechanical properties of tuff￣typed tunnel ballast machine￣made sand concrete

ZHANG Guangtian1，2，3， LIU Juanhong1， LIU Kun1， FU Shifeng2，3， LIU Dongji2，3

(1 College of Civil and Resources， University of Science and Technology Beijing， Beijing 100083， China； 2 Hebei

Academy of Building Research， Shijiazhuang 050021， China； 3 Hebei Province Science and Technology Key Laboratoryof Solid Waste for Building Materials， Shijiazhuang 050021， China)

Abstract: Using the tunnel ballast of Hangzhou shaotai expressway， tuff￣typed machine￣made sand was prepared. Thecharacteristics of machine￣made sand and stone powder were analyzed， and their effects on the fluidity and strength ofmortar and concrete were studied. Strip sieve was used to detect the flake particles in the machine￣made sand and explorethe influence of different flake particles contect on the workability of mortar and concrete， and the impact of different sandrates on concrete performance of C30 and C35 was studied. The test results show that the tuff￣typed machine￣made sand issiliceous machine￣made sand， and the broken bond on the surface causes the stone powder to easily agglomerate， and it isnot sensitive to the methylene blue value， and requires a large amount of water. As the content of stone powder and flakyparticles increases， the fluidity and strength of mortar and concrete continue to decrease. The influence of contect of flakeparticles of tuff on the strength is greater than that of contect of limestone flake particles， and the influence of contect offlake particles on the fluidity and strength of mortar with low water￣binder ratio is greater than that of high water￣binderratio. Considering the workability and compressive strength of concrete， the stone powder content in machine￣made sandshould be less than 8%， and the contect of flake particles should be less than 10%， and the selected C30 sand rate is43%， and the C35 sand rate is 41%.

Keywords: tuff； limestone； machine￣made sand； workability； flowability； stone powder； flake particle

∗国家自然科学基金面上项目(51678049)，国家自然科学基金重点项目(51834001)，河北省重点研发计划(19274104D)。

第一作者:张广田，博士，高级工程师，主要从事固废资源化利用、高品质砂石、尾矿资源化利用等方面研究，Email:syzx1206@163.com。

[引用本文] 张广田，刘娟红，刘昆，等. 凝灰岩型隧道洞砟机制砂混凝土和易性与力学性能研究[ J]. 建筑结构，2022，52(2):120￣126. ZHANG Guangtian， LIU Juanhong， LIU Kun， et al. Study on workability and mechanical propertiesof tuff￣typed tunnel ballast machine￣made sand concrete[J]. Building Structure，2022，52(2):120￣126.