摘要
对南方某药剂稳定化飞灰填埋场的钻孔试样(5个龄期、3处埋深)开展室内土工特性测试,包括颗粒级配、相对密度、水质量分数、持水量、渗透系数、压缩特性、抗剪强度等.试验结果表明:稳定化飞灰的平均粒径为0.8～3.1 mm,接近于粗砂或细砾;不均匀系数为4.56～10.33,曲率系数为0.32～0.43,属于级配不良;相对密度为1.68～2.56;水质量分数为16.6%～46.4%,持水量为23.9%～56.7%,具有吸水性能;渗透系数为9.1×10–5～4.5×10–3 cm/s,随着上覆应力的增大而减小;压缩系数为1.21～1.93 MPa–1,具有高压缩性;修正主压缩指数为0.13～0.18;内摩擦角为32.9°～34.2°,黏聚力为14.0～19.5 kPa,后者主要来源于稳定化飞灰的胶结特性;随着龄期的增长,稳定化飞灰的胶结结构逐渐弱化,导致稳定化飞灰的粒径和相对密度减小、持水量增大、渗透系数和抗剪强度降低.对比分析稳定化飞灰的工程特性与生活垃圾的差异,对稳定化飞灰填埋场的设计、运营和管理提出了相应的工程建议.
Laboratory tests were conducted to analyze the geotechnical properties of chemically stabilized municipal solid waste incineration (MSWI) fly ash. The borehole samples were obtained from a landfill in southern China, which covered five different fill ages and three different burial depths. The measurements involved grain-size distribution, relative density, water content, moisture retention capacity, permeability coefficient, compression property, shear strength, etc. The mean diameter was 0.8-3.1 mm, which was close to coarse sand or fine gravel. The non-uniform coefficient and curvature coefficient were 4.56-10.33 and 0.32-0.43, respectively. The stabilized fly ash was poorly graded. The relative density was 1.68-2.56. The moisture content and moisture retention capacity were 16.6%-46.4% and 23.9%-56.7%, respectively. There is water absorbing capacity for the stabilized fly ash. The permeability coefficient was 9.1×10^-5-4.5×10^–3 cm/s, which decreased with increasing stress. The primary compression ratio and compression coefficient were 0.13-0.18 and 1.21-1.93 MPa^–1, respectively. The stabilized fly ash has the property of high compressibility. The cohesive force and friction angle were 14.0-19.5 kPa and 32.9°-34.2°, respectively. The cohesion is mainly contributed by the cementing properties of the stabilized fly ash. The cementitious structure of the stabilized fly ash might be deteriorated with increasing fill age, which resulted in decreases in grain size, relative density, permeability coefficient and shear strength, and an increase in moisture retention capacity. The comparison analysis was conducted between the present results and the references' data for MSW. Engineering comments were proposed for the design, operation and management of the stabilized MSWI fly ash landfills.
作者
徐辉
缪建冬
陈萍
詹良通
罗小勇
XU Hui;MIAO Jian-dong;CHEN Ping;ZHAN Liang-tong;LUO Xiao-yong(School of Civil Engineering and Architecture, Zhejiang Sci-Tech University, Hangzhou 310018, China;MOE KeyLaboratory of Soft Soils and Geoenvironmental Engineering, Zhejiang University, Hangzhou 310058, China;Shanghai Municipal Engineering Design Institute (Group) Co., Ltd, Shanghai 200092, China)
出处
《浙江大学学报（工学版）》
EI
CAS
CSCD
北大核心
2019年第1期1-10,共10页
Journal of Zhejiang University：Engineering Science
基金
国家自然科学基金资助项目(5157081460
51708508)
住建部科技计划资助项目(2015R3002)
软弱土与环境土工教育部重点实验室(浙江大学)开放基金资助项目(2017P03)
关键词
稳定化飞灰
持水量
渗透性
压缩性
抗剪强度
stabilized municipal solid waste incineration fly ash
moisture retention capacity
permeability
compressibility
shear strength
