西安建筑科技大学学报(自然科学版)

库水位上升产生的浮力作用,将改变原来的水-边坡作用环境,不利于库区边坡稳定.结合茨哈峡4#倾倒体现场踏勘调研情况,根据倾倒体的环境地质条件,探讨了该库岸倾倒体的成因机制和演化过程.利用数值模拟方法,采用FLAC3D有限差分软件建立三维模型,运用强度折减理论对该库岸倾倒边坡的稳定性进行了计算分析,将边坡关键点处的位移是否突变和塑性区是否贯通作为边坡的失稳判据.结果表明:倾倒体的稳定性受库水位上升的影响较为明显; 倾倒体在天然状况下是稳定的,此时倾倒体的稳定系数为1.78; 随着库水位的上升,倾倒体安全系数逐渐降低,当库水位上升至2 990 m(水位355 m)时,倾倒体的稳定系数为最小,其值为1.12,小于边坡设计安全系数.为了确保安全,建议对该倾倒体采取监控措施.

The buoyancy caused by the rise of the reservoir water level will change the original environment of water-slope interaction, which is not conducive to the stability of the slope in the reservoir area. Based on the site investigation of the toppling mass in 4# toppling slope of Cihaxia Hydropower Station and the corresponding geological environment, the genetic mechanism and evolution process of the toppling mass at the bank of the reservoir were discussed. By using the numerical simulation method and the FLAC3D finite difference software, a three-dimensional model is established, and the stability of the toppling slope of the reservoir bank is calculated and analyzed by strength reduction theory. The displacement of the slope at the critical point and the consistency of the plastic zone is through are taken as the criterions for slope instability. The results show that:(1)and the consistency of the stability of toppling mass is obviously affected by the rise of the reservoir water level.(2)The toppling mass is naturally stable with the stability coefficient at 1.78.(3)With the increase in water level of the reservoir, the safety factor of toppling mass decreases gradually. When water level of reservoir rises to 2 990 m(Water level 355 m), the stability coefficient of the toppling mass is the smallest as 1.12, which is less than safety factor of slope as designed. To ensure safety, it is recommended to monitor such kind of toppling mass.

引言
1 工程概况
2 数值模型和计算参数
3 4#倾倒体三维结果分析
4 结论

图1 4#倾倒体地形地貌特征<br/>Fig.1 4#Dumping landform characteristic

图1 4#倾倒体地形地貌特征
Fig.1 4#Dumping landform characteristic

图2 4#倾倒体表部冲沟<br/>Fig.2 The surface gullies of 4# toppling slope

图2 4#倾倒体表部冲沟
Fig.2 The surface gullies of 4# toppling slope

图3 4#倾倒体三维地质概化模型<br/>Fig.3 3D generalization geological model of 4# dump

图3 4#倾倒体三维地质概化模型
Fig.3 3D generalization geological model of 4# dump

图4 三维计算模型及监测点示意图<br/>Fig.4 Three-dimensional calculation model and key schematic

图4 三维计算模型及监测点示意图
Fig.4 Three-dimensional calculation model and key schematic

图5 三维计算模型分离示意图<br/>Fig.5 Three dimensional calculation separation model

图5 三维计算模型分离示意图
Fig.5 Three dimensional calculation separation model

表1 结构面参数选取表<br/>Tab.1 Structural plane parameters selection table

表1 结构面参数选取表
Tab.1 Structural plane parameters selection table

表2 边坡岩体参数选取表<br/>Tab.1 Slope rock mass parameters selection table

表2 边坡岩体参数选取表
Tab.1 Slope rock mass parameters selection table

图6 各关键点位移速度与折减系数关系曲线<br/>Fig.3 Displacement speed of the key point and the reduction factor relationship curve

图6 各关键点位移速度与折减系数关系曲线
Fig.3 Displacement speed of the key point and the reduction factor relationship curve

图7 塑性区及剪应变增量与速度云图<br/>Fig.7 The plastic zone, the shear strain increment and velocity contours

图7 塑性区及剪应变增量与速度云图
Fig.7 The plastic zone, the shear strain increment and velocity contours

图8 各关键点位移速度与折减系数关系曲线<br/>Fig.8 Displacement speed of the keypoint and the reduction factor relationship curve

图8 各关键点位移速度与折减系数关系曲线
Fig.8 Displacement speed of the keypoint and the reduction factor relationship curve

图9 塑性区及剪应变增量与速度云图<br/>Fig.9 The plastic zone, the shear strain increment and velocity contours

图9 塑性区及剪应变增量与速度云图
Fig.9 The plastic zone, the shear strain increment and velocity contours

图10 各关键点位移速度与折减系数关系曲线<br/>Fig.10 Displacement speed of the key point and the reduction factor relationship curve

图10 各关键点位移速度与折减系数关系曲线
Fig.10 Displacement speed of the key point and the reduction factor relationship curve

图11 塑性区及剪应变增量与速度云图<br/>Fig.11 The plastic zone, the shear strain increment and velocity contours

图11 塑性区及剪应变增量与速度云图
Fig.11 The plastic zone, the shear strain increment and velocity contours

图12 各关键点位移速度与折减系数关系曲线<br/>Fig.12 Displacement speed of the key doint and the reduction factor relationship curve

图12 各关键点位移速度与折减系数关系曲线
Fig.12 Displacement speed of the key doint and the reduction factor relationship curve

图13 塑性区及剪应变增量与速度云图<br/>Fig.13 the plastic zone, the shear strain increment and velocity contours

图13 塑性区及剪应变增量与速度云图
Fig.13 the plastic zone, the shear strain increment and velocity contours

表3 各工况下安全系数汇总表<br/>Tab.3 The safety coefficient under the condition of the summary table

表3 各工况下安全系数汇总表
Tab.3 The safety coefficient under the condition of the summary table

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备注

引言

1 工程概况

2 数值模型和计算参数

3 4#倾倒体三维结果分析

4 结论

期刊信息