Experimental Study on Performance of Intensively Weathered Mica Schist Stabilized by the Combination of CLFD and Tailings Slag

LI Yong-jing; WEN Cheng-zhang; WANG Song; CHENG Yao-hui; HAO Wen-jie

doi:10.11988/ckyyb.20220784

PDF(5012 KB)

Journal of Changjiang River Scientific Research Institute ›› 2023, Vol. 40 ›› Issue (12) : 88-95. DOI: 10.11988/ckyyb.20220784

Rock-Soil Engineering

Experimental Study on Performance of Intensively Weathered Mica Schist Stabilized by the Combination of CLFD and Tailings Slag

LI Yong-jing^1,2, WEN Cheng-zhang¹, WANG Song¹, CHENG Yao-hui¹, HAO Wen-jie¹

Author information +

History +

Abstract

To address the low strength issue of mica schist, we propose a new type of powder curing agent (CLFD) consisting of cement, lime, fly ash, and desulfurized gypsum to enhance subgrade soil in association with tailings slag (TS). Mechanical and durability properties of solidified soil with varying amount of curing agent and curing age were investigated through indoor mechanical tests. By adopting X-ray diffraction analysis and scanning electron microscope test, the mechanism of strength formation in solidified soil was revealed. Results suggest that soil samples solidified with CLFD-TS exhibit significant improvements in mechanical properties, water stability, and dry-wet cycle resistance. A mixing ratio of curing agent no less than 6% when immersed in water for 9 days meets specification requirements in terms of bearing ratio and modulus of resilience. Microscopic analysis shows the presence of C-S-H, C-A-H gel, AFt, and CaSO₄ crystals in the solidified soil, which enhance soil properties by cementing and filling soil particles. Early strength of CLFD-TS-solidified soil comes from the physical skeleton gradation improvement provided by tailings slag and the hydration effect of cement components. Late strength is provided by the pozzolanic effect of the curing agent. Finally, a micro mechanism model of CLFD-TS-solidified soil is proposed to provide a theoretical basis for similar studies.

Key words

road engineering / mica schist strongly weathered soil / CLFD curing agent / mechanical property / curing mechanism

Cite this article

EndNote

Ris (Procite)

Bibtex

Download Citations

LI Yong-jing, WEN Cheng-zhang, WANG Song, CHENG Yao-hui, HAO Wen-jie. Experimental Study on Performance of Intensively Weathered Mica Schist Stabilized by the Combination of CLFD and Tailings Slag[J]. Journal of Changjiang River Scientific Research Institute. 2023, 40(12): 88-95 https://doi.org/10.11988/ckyyb.20220784

References

[1] 中国发改环资(2021)381号.关于“十四五”大宗固体废弃物综合利用的指导意见[EB/OL].[2021-03-18]. https://www.ndrc.gov.cn/xxgk/zcfb/tz/202103/t20210324_1270286.html.
[2] WANG D, ZHU J, WANG R. Assessment of Magnesium Potassium Phosphate Cement for Waste Sludge Solidification: Macro- and Micro-Analysis[J]. Journal of Cleaner Production, 2021, 294: 126365.
[3] GE Z, YUAN H, SUN R, et al. Use of Green Calcium Sulphoaluminate Cement to Prepare Foamed Concrete for Road Embankment: A Feasibility Study[J]. Construction and Building Materials, 2020, 237: 117791.
[4] WU S, YAO Y, YAO X, et al. Co-preparation of Calcium Sulfoaluminate Cement and Sulfuric Acid through Mass Utilization of Industrial By-product Gypsum[J]. Journal of Cleaner Production, 2020, 265: 121801.
[5] WEN P, WANG C, SONG L, et al. Durability and Sustainability of Cement-Stabilized Materials Based on Utilization of Waste Materials: A Literature Review[J]. Sustainability, 2021, 13(21): 11610.
[6] 米吉福, 汪浩, 刘晶冰, 等. 土壤固化剂的研究及应用进展[J]. 材料导报, 2017, 31(增刊1): 388-391, 401.
[7] 力乙鹏,李婷.土壤固化剂的固化机理与研究进展[J].材料导报,2020, 34(增刊2): 273-1277,1298.
[8] 纪小平, 代聪, 崔志飞, 等. 固化剂稳定磷石膏路基填料的工程特性研究[J]. 中国公路学报, 2021, 34(10): 225-233.
[9] 朱志铎, 郝建新, 周礼红. 固化粉质土应力应变特性试验研究[J]. 岩土力学, 2008, 29(8): 2199-2202.
[10]刘松玉, 张涛, 蔡国军. 工业废弃木质素固化改良粉土路基技术与应用研究[J]. 中国公路学报, 2018, 31(3): 1-11.
[11]陈锐, 郝若愚, 李笛, 等. 碱激发材料固化低液限粉黏土路用性能及抗冻融特性研究[J]. 工程地质学报, 2022, 30(2): 327-337.
[12]WU D, CHEN K, ZHANG Z, et al. Influence of some Additives on the Properties of OPC Solidified Sandy Silt[J]. Applied Sciences, 2021, 11(16): 7252.
[13]KAMPALA A, JITSANGIAM P, PIMRAKSA K, et al. An Investigation of Sulfate Effects on Compaction Characteristics and Strength Development of Cement-Treated Sulfate Bearing Clay Subgrade[J]. Road Materials and Pavement Design, 2020, 22(10): 1-14.
[14]LANG L, SONG C, XUE L, et al. Effectiveness of Waste Steel Slag Powder on the Strength Development and Associated Micro-mechanisms of Cement-Stabilized Dredged Sludge[J]. Construction and Building Materials, 2020, 240: 117975.
[15]LIU L, ZHOU A, DENG Y, et al. Strength Performance of Cement/Slag-based Stabilized Soft Clays[J]. Construction and Building Materials, 2019, 211: 909-918.
[16]REN C,WANG W,LI G. Preparation of High-performance Cementitious Materials from Industrial Solid Waste[J]. Construction and Building Materials,2017,152:39-47.
[17]雷俊安, 杨俊. 二灰稳定三峡库区风化砂三轴试验研究[J]. 长江科学院院报, 2019, 36(3): 133-138.
[18]周小文, 罗兴财. 全风化花岗岩与花岗岩残积土的判别及物理力学性质对比[J]. 长江科学院院报, 2022, 39(4): 1-7.
[19]孙仁娟, 方晨, 高发亮, 等. 基于固弃物的固化土路用性能及固化机理研究[J]. 中国公路学报, 2021, 34(10): 216-224.
[20]陈瑞敏, 简文彬, 张小芳, 等. CSFG-FR协同作用改良淤泥固化土性能试验研究[J]. 岩土力学, 2022, 43(4): 1020-1030.
[21]王子帅,王东星.工业废渣-水泥协同固化土抗硫酸盐侵蚀性能[J].岩土工程学报,2022,44(11):2035-2042.
[22]JTG 3430—2020,公路土工试验规程[S]. 北京: 人民交通出版社, 2020.
[23]郭万里, 朱俊高, 温彦锋. 对粗粒料4种级配缩尺方法的统一解释[J]. 岩土工程学报, 2016, 38(8): 1473-1480.
[24]JTG E51—2009,公路工程无机结合料稳定材料试验规程[S]. 北京: 人民交通出版社, 2009.
[25]JTG D50—2017,公路沥青路面设计规范[S]. 北京: 人民交通出版社, 2017.
[26]JTG D30—2015,公路路基设计规范[S]. 北京: 人民交通出版社, 2015.