Stability Assessment and Optimization Design of Lakeside Open-Pit Slope considering Fluid-Solid Coupling Effect

Abstract

Chengmenshan copper mine, located at Jiujiang city in the Jiangxi Province, is a rarely lakeside open-pit mine in China. Since the open-pit is very close to Sai Lake, the seasonally changed water level and the distance between lake and slope have great influence to the stability of open-pit slope. Based on the drill data and geological sections, a numerical model of the slope is built. With the fluid-mechanical interaction associated, the stability of the slopes is numerically analyzed, in which different lake water levels and lake-slope distances are taken into consideration. The comparative analysis shows that a larger lake-slope distance can promise better slope stability and weaken the sensitivity of slope stability to water. The stability of slopes with different heights is analyzed to find that the stability weakens and the sensitivity is enhanced with the height increasing. To the most serious situation, the slope height and the lake water level being 238 m and 17.2 m, respectively, the value equals 1.18945 which is extremely closed to the allowable safety factor of 1.20 for slope design. According to the minimum for slope design, the minimum distance between lake and open-pit slope is found to be 60 m.

Slope geometry optimization considering groundwater drawdown scenarios at an open-pit phosphate mine, southeastern Brazil

“…While the friction angle values did not vary much, the values of the cohesion parameter were distributed between 10 and 100 kPa. The listed Mohr-Coulomb strength parameters were found to be slightly higher than weathered marls(Cooper et al 2019) and quaternary deposits(Fan et al 2015) of mines excavated in unconsolidated materials, but are similar to values used in modeling rainstorm-induced soil landslides in southeastern Brazil(Gomes et al 2017). These parameters were used next to assess the impact of different groundwater drawdown scenarios on the stability of the soil-mantled open-pit mine.…”

Stability Analysis of Mineral Structures using FLAC Software

“…Theoretical study and practical experience show that surface mine slopes typically experience four stages of drilling completion to collapse according to Mohr -Columb, shear criteria: elastic stage, nonlinear deformation stage, creep deformation stage, and decay stage. For rock slopes, this means a large reduction in stability [4]. Most numerical methods used to solve rock engineering problems can be categorized into three main groups: 1.…”

“…Itasca FLAC3D software has been widely used in the analysis of underground tunnels, open pit mines, and complex underground mines in terms of gravity, groundwater, and other factors. But there are some problems in building a complex numerical model using FLAC3D alone [4]. FLAC 3D is applied to create a model based on topography obtained from field measurements.…”

Stability Satisfied Design and Construction of Excavated Soil Dumps in a Soft Soil Region in China

“…The potential slide surfaces of the soil dump with different heap heights at a fixed slope gradient of 1:2.50 are shown in Figure 4A. The potential slide surface is determined by connecting the mutation points of the displacement in the slope (Fan et al, 2015), and the results are presented with dotted lines. It is seen that all the simulation cases indicate a typical circular arc failure mode of the soil dump.…”