Study Of The Characteristics And Treatment Of Unstable Slopes In The West Foot Of DongYue Mountain In Guyuan City,NingXia

Dongyuan montain is located in Qinghe tonw in Yuanzhou district of Guyuan,the west margin of Dongyue montain is closed to urban area of Guyuan city. It is thetransition zone of loess hilly and valley plain. The special topograpy and geomorphyconditions, fragile geological environment, and intense human engineering activitiesaccelerat the loess slope′s instability.8unstable slopes are observed in15km2in the west margin of Dongyuemontain, this kind of high and steep slopes of soil with poor stability are all caused byhuman engineering activity, not only threaten the safety of surrounding, but also takebad effect to the image of the city.In order to treat the unstable slopes in this area, in the present study, thetreatment of w3unstable slope was taken as an example. Based on previous workinformation, understanding the basic situation of geological disasters in the studyarea，we carry out field investigation work to master the topography, geomorphology,strata and human engineering activities in the study area. After a comprehensiveunderstanding of the characteristic of deformation of geological disasters, andanalyzing the forming conditions, we preliminary assess the dangers and the damagedegree of disasters.Through1:500topographic survey, exploration drilling and testing analysis, etc,synthesize geology situation of research area, then select the control measures ascutting slope measures combine with bioremediation.In the cutting slope grade design, preliminary design platform is2m wide,platform height is5m, slope ratio is1:2.0, horizontal steps is10m. According to theproposed parameters, using Lizheng software to analyze the slope stability. In order toimprove the precision of calculation, the horizontal plane of the slope body wasdivided into12sections. The results show that the safety coefficient can meet therequirements, and the selected parameter is reasonable. While taking chioce ofplanting trees, insist on the principle of matching species with the site, combine withthe experience of locally grown to compatible with the surrounding greening effect. Select pinus and tabulaeformis as macrophanerophytes, sainfoin as herbaceous plant.Through management, can greatly improve the stability of the slope body and security,achieve the effect of security protection to residents, road, grain depot and others.The increase of the vegetation coverage can effectively improve the geologicalenvironment conditions.After governance, steep slope evolved into ladder-like gentle slope with lowerslope angle, planting trees and grass on the ladder-like gentle slope can reduce thewater loss and soil erosion, can solid soil and protect slope, can also improve thestability of the slope, avoid adding other slope protection engineering. Overall, thiskind measure has low construction difficulty, small investment, with strongpracticability and maneuverability.Acording to the experience of the W3unstable slope′s governance, the other7unstable slopes can be considered the same governance measures in future. As highand steep soil slopes are most popular in research area, the study could provide areference for treatment to unstable slopes in similar areas.