摘要
为评价包边土和土工格栅处置铁尾矿砂路基的效果,充分认识铁尾矿砂填筑路基的适用性,并提高其利用率,对4种工况的铁尾矿砂路基(6m填高)的沉降和稳定性进行有限元数值计算。4种工况分别为:无包边土,无土工格栅(工况Ⅰ);有包边土,无土工格栅(工况Ⅱ);有包边土,包边土与铁尾矿砂交接处铺设三向土工格栅(工况Ⅲ);有包边土,满面铺设三向土工格栅(工况Ⅳ)。研究结果表明:工况Ⅰ、Ⅱ、Ⅲ、Ⅳ的最大工后(600d)沉降分别为19.547、19.711、19.540、18.298cm;固结阶段路面顶面中央处的沉降以工况Ⅳ最小,工况Ⅱ最大;最大水平位移发生在坡脚下7~8m处,其次发生在土路肩边缘处,坡脚下水平位移向路基外侧发展,而土路肩处水平位移向路基内侧发展;工况Ⅳ潜在滑移面贯穿至基底5m深度处,工况Ⅰ潜在滑移面位于路基边坡上,其抵抗滑移的能力最差;同时满面铺设土工格栅和设置包边土对提高路基稳定性的效果最为明显,安全系数可提高0.9;铺设土工格栅可有效减小铁尾矿砂路基顶面边缘的侧向位移,对有效预防路基路面纵向开裂具有积极作用,但其不能有效减小基底侧向位移;黏土包边提高了铁尾矿砂路基的稳定性,但加大了路基的不均匀沉降;设置包边土和铺设土工格栅的处置措施对提高填方边坡稳定性效果比减小沉降效果明显。
In order to evaluate the effect of tailings subgrade, fully understand the a improve their utilization, settlement and subgrade （6 m embankment height） were wrapping soil and geogrid on the pplicability of iron ore tailings stability of four kinds of cases analyzed by finite element nume treatment of iron ore filling subgrade and of iron ore tailings rical method, which were as followed, no wrapping soil and no geogrid （case Ⅰ ） ; wrapping soil and no geogrid （case Ⅱ）; wrapping soil and three-way geogrid laid on the junction of wrapping soil and iron ore tailings （case Ⅲ） ; wrapping soil and three-way geogrid laid on all the wrapping soil and iron ore tailings （case Ⅳ）. The results show that the maximum settlement after construction （600 d） of case Ⅰ , Ⅱ , Ⅲ and Ⅳ are 19. 547, 19. 711, 19. 540 and 18. 298 em, respectively. The settlement of central place at the top of pavement are maximum in case I and minimum in case Ⅱ in the consolidation stage. The maximum horizontal displacement occurs at the foot of slope with 7 to 8 m, which is followed by the edge of the soil shoulder. Horizontal displacement at the foot of slope occurs towards to the outside of subgrade and that of soil shoulder towards to the inside of subgrade. Potential slip surface of case IV develops into the depth of 5 m of basement. The potential slip surface of case I is located on the slope of subgrade, and its ability of anti-slippage is the worst, and case IV can evidently improve the subgrade stability which safety factor can be increased by 0.9. Laying geogrid can effectively reduce the lateral displacement of surface edge on the top of subgrade of iron ore railings, which has a positive effect on the effective prevention of subgrade and pavement longitudinal cracking, but which can not effectively reduce the lateral displacement of the basement. Clay wrapping relatively improves the stability of iron ore tailings subgrade but increases the differential settlement of subgrade. Moreover, soil-wrapping
作者
牛玺荣
孙延芳
NIU Xi-rong;SUN Yan-fang(Department of Civil Engineering, Shanxi University, Taiyuan 030013, Shanxi, China;Key Laboratory of Highway Construction ＆ Maintenance Technology in Loess Regions of Ministry of Transport, Shanxi Transportation Research Institute, Taiyuan 030006, Shanxi, China;College of Architecture and Civil Engineering, Taiyuan University of Technology, Taiyuan 030024, Shanxi, China)
出处
《长安大学学报（自然科学版）》
EI
CAS
CSCD
北大核心
2018年第1期9-16,共8页
Journal of Chang’an University(Natural Science Edition)
基金
山西省自然科学基金项目(201701D121068)
山西省交通科研计划项目(16-1-7)
山西省交通建设科技项目(11-2-16)
黄土地区公路建设与养护技术交通行业重点实验室开放基金项目(KLTLR-Y12-9
KLTLR-Y14-17)
关键词
道路工程
铁尾矿砂
数值计算
沉降
稳定性
road engineering
iron ore tailing
numerical analysis
settlement
stability
