The E24 profile slope analyzed belongs to a series of excavated slopes of the Haizhou Opencast Coal Mine. It seems to be divided into Downslope Part and Upslope Part. Its profile comprises two noticeable coal seams, c...The E24 profile slope analyzed belongs to a series of excavated slopes of the Haizhou Opencast Coal Mine. It seems to be divided into Downslope Part and Upslope Part. Its profile comprises two noticeable coal seams, called the 8# and 9# weak layers, considered as the potential failure surfaces. In consideration of the actual configuration as in the perspective of any modification, assessing the stability of this slope with various profile forms under given conditions, and assessing the risk of instability and quantifying the influence of earthworks or other modifications to the stability of this slope, have constituted the primordial objectives carried out. From assumed potential failure surfaces, any specific profiles and specified slip surfaces are defined. A factor of safety (FoS) is computed for each specified slip surface; the smallest FoS found corresponds to the least favorable slip surface. The safety factor values obtained are compared to the suggested safety factor. Limit equilibrium methods of vertical slices implemented in Slope/W, computer program for slope stability analyses, have been adopted to perform the E24 slope stability analysis. The safety factor values computed with 9# weak layer are lower than for 8#; the factors of safety obtained with Sarma's method are the smallest; more, without groundwater (long term) overall values are greater than those determined under groundwater condition (short term). The lowest safety factor value is found for a profile depending on an adopted earthwork sequence. The E24 profile slope stability analysis shows the instability risk for the deepest weak layer, and also shows the short and long term stability of this slope for the envisaged earth movements. However it demonstrates the existence of instability risk for any earthwork firstly affecting the downslope part.展开更多
植被重建是治理排土场边坡水土流失最直接也是最有效的生物措施,研究不同植被重建模式下土壤有机碳（SOC）和全氮（TN）含量的空间分布规律是筛选适宜排土场边坡生长的植被模式的重要条件。选取内蒙古黑岱沟露天煤矿治理15年的排土场边...植被重建是治理排土场边坡水土流失最直接也是最有效的生物措施,研究不同植被重建模式下土壤有机碳（SOC）和全氮（TN）含量的空间分布规律是筛选适宜排土场边坡生长的植被模式的重要条件。选取内蒙古黑岱沟露天煤矿治理15年的排土场边坡中4种植被重建模式（自然恢复地、草地、灌木林、乔木林）,采集270个土壤剖面（0~100 cm）样品,研究不同重建模式下SOC储量的变化。结果表明：（1）植被重建模式显著影响剖面SOC、TN含量及分布（p〈0.05）,0~10 cm和10~20 cm SOC、TN均呈草地〉灌木〉乔木〉自然恢复地,20 cm以下各土层SOC、TN虽然也表现相似的特征,但差异随土层深度增加越来越小。（2）剖面SOC密度和储量表现为原地貌区〉治理排土场〉新建排土场。经15年植被重建后,排土场边坡表现出巨大的固碳能力,1 m深度的林地和草地碳储量分别增加了5.38、11.85 t hm^-2,但仅原地貌水平的1/2和3/5。（3）林地和草地的固碳速率分别为35.87、79.01 g m^-2a^-1,草地的固碳速率是林地的2.2倍,从土壤固碳及水土流失防治的角度考虑,建议矿区排土场边坡植被重建优先选择草地,其次灌木。展开更多
基金Project of NSFC (No. 40472136)Scientific Research Foundation for the Returned Overseas Chinese Scholar, State Education Ministry(No. 120413133)985 Project of Jilin University (No. 105213200500007)
文摘The E24 profile slope analyzed belongs to a series of excavated slopes of the Haizhou Opencast Coal Mine. It seems to be divided into Downslope Part and Upslope Part. Its profile comprises two noticeable coal seams, called the 8# and 9# weak layers, considered as the potential failure surfaces. In consideration of the actual configuration as in the perspective of any modification, assessing the stability of this slope with various profile forms under given conditions, and assessing the risk of instability and quantifying the influence of earthworks or other modifications to the stability of this slope, have constituted the primordial objectives carried out. From assumed potential failure surfaces, any specific profiles and specified slip surfaces are defined. A factor of safety (FoS) is computed for each specified slip surface; the smallest FoS found corresponds to the least favorable slip surface. The safety factor values obtained are compared to the suggested safety factor. Limit equilibrium methods of vertical slices implemented in Slope/W, computer program for slope stability analyses, have been adopted to perform the E24 slope stability analysis. The safety factor values computed with 9# weak layer are lower than for 8#; the factors of safety obtained with Sarma's method are the smallest; more, without groundwater (long term) overall values are greater than those determined under groundwater condition (short term). The lowest safety factor value is found for a profile depending on an adopted earthwork sequence. The E24 profile slope stability analysis shows the instability risk for the deepest weak layer, and also shows the short and long term stability of this slope for the envisaged earth movements. However it demonstrates the existence of instability risk for any earthwork firstly affecting the downslope part.
文摘植被重建是治理排土场边坡水土流失最直接也是最有效的生物措施,研究不同植被重建模式下土壤有机碳（SOC）和全氮（TN）含量的空间分布规律是筛选适宜排土场边坡生长的植被模式的重要条件。选取内蒙古黑岱沟露天煤矿治理15年的排土场边坡中4种植被重建模式（自然恢复地、草地、灌木林、乔木林）,采集270个土壤剖面（0~100 cm）样品,研究不同重建模式下SOC储量的变化。结果表明：（1）植被重建模式显著影响剖面SOC、TN含量及分布（p〈0.05）,0~10 cm和10~20 cm SOC、TN均呈草地〉灌木〉乔木〉自然恢复地,20 cm以下各土层SOC、TN虽然也表现相似的特征,但差异随土层深度增加越来越小。（2）剖面SOC密度和储量表现为原地貌区〉治理排土场〉新建排土场。经15年植被重建后,排土场边坡表现出巨大的固碳能力,1 m深度的林地和草地碳储量分别增加了5.38、11.85 t hm^-2,但仅原地貌水平的1/2和3/5。（3）林地和草地的固碳速率分别为35.87、79.01 g m^-2a^-1,草地的固碳速率是林地的2.2倍,从土壤固碳及水土流失防治的角度考虑,建议矿区排土场边坡植被重建优先选择草地,其次灌木。
