开采引起上覆公路地表沉降与变形的数值分析

Numerical analysis of deformation and ground surface settlement of overlying road caused by exploiting

由于开采的需要,某矿群已从露天转入地下开采,在其开采境界内上部有一条乡镇公路穿过,为最大限度地回收资源和保证上部公路的安全运行,通过岩体宏观结构调查分析、取样、室内岩石力学试验和工程类比,综合确定岩体力学参数;并采用三维有限元对三种不同的开采方案引起公路地表的沉降高度进行了卸荷模拟和数值计算,模拟计算结果表明:随着开采高度的增加,公路地表沉降高度呈非线性增加,开采高度越高,其地表沉降高度越大,开采高度采超过1300水平时,上部围岩将处于不稳定状态,影响公路的安全运行。通过工业试验,开采高度定为1300水平时,其沉降高度在15 cm以内,能够保证上覆公路的安全运行。

3#ore cluster is striped mining turn into underground due to exploiting requirement;and the parameters of rock mass mechanics are determined by way of rock structure investigation,sampling,indoor rock mechanics experiment and engineering analogy its aim to reclaiming resource mostly and guaranteeing 3#ore cluster overlying rural road safety operation;then unloading simulation with 3D finite elements is applied based on three exploiting scheme methods;the simulation results are as fellows:the settlement height of road ground surface is increased nonlinearly with increasing height of exploitation;and the more exploiting height,the more settlement height;the height of settlement is 7cm,20 cm,50 cm and 135 cm when exploitation horizon is 1288,1300,1310 and 1320 correspondingly.The stabilization of rock mass would be damaged when exploiting horizon is more than 1300.The settlement height is less than 15 cm by commercial test while exploiting horizon in 1300,which could be guaranteed safety of road operation.The method of applying with synthesis analysis of rock mass mechanics parameters and unloading simulation to analyze rock mass stabilization is effective and feasible by commercial test.