Numerical analysis on settlement and stability of iron ore tailings subgrade(PDF)
长安大学学报（自然科学版）[ISSN:1006-6977/CN:61-1281/TN]
- Issue:
- 2018年01期
- Page:
- 9-16
- Research Field:
- 道路工程
- Publishing date:
Info
- Title:
- Numerical analysis on settlement and stability of iron ore tailings subgrade
- Author(s):
- NIU Xi-rong; SUN Yan-fang
- 1. Department of Civil Engineering, Shanxi University, Taiyuan 030013, Shanxi, China; 2. Key Laboratory of Highway Construction & Maintenance Technology in Loess Regions of Ministry of Transport, Shanxi Transportation Research Institute, Taiyuan 030006, Shanxi, China; 3. College of Architecture and Civil Engineering, Taiyuan University of Technology, Taiyuan 030024, Shanxi, China
- Keywords:
- road engineering; iron ore tailing; numerical analysis; settlement; stability
- PACS:
- U418.5
- DOI:
- -
- Abstract:
- In order to evaluate the effect of wrapping soil and geogrid on the treatment of iron ore tailings subgrade, fully understand the applicability of iron ore tailings filling subgrade and improve their utilization, settlement and stability of four kinds of cases of iron ore tailings subgrade (6 m embankment height) were analyzed by finite element numerical 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 cm, 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 tailings, 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 and geogrid-laying measures are more effective to improve the subgrade stability than to reduce the subgrade settlement.
Last Update: 2018-02-05