考虑损伤累积效应的矿山边坡稳定性分析及加固方案研究

Study on the Stability Analysis and Reinforcement Scheme of Mine Slope Considering Damage Accumulation Effect

矿山开采过程中,爆破作为一种极其常用的手段,对周围岩体产生了不可逆转的损伤,一旦超过岩体的损伤极限,将会造成边坡失稳,导致严重的安全生产事故。通过声波测试技术,以声波波速为介质定义了损伤变量,用于描述岩石的损伤程度,对矿山爆破损伤累积效应进行了现场测试,基于现场实测结果建立了考虑累积效应的损伤模型。将该模型进行二次开发,导入FLAC数值模拟软件,对持续爆破条件下矿山边坡的稳定性进行了分析,并提出了加固方案。研究表明:(1)随着岩体经历爆破次数增加,内部损伤程度逐渐增加,最终以突变激增的形式达到完全破坏;(2)通过拟合试验过程中损伤变量与爆破次数、爆破装药量的关系,认为损伤变量的增长与爆破次数的指数关系成正比,同时与爆破装药量的0.5次方成正比;(3)对频繁爆破条件下的边坡稳定性控制方法进行了分析,所提加固方案有助于控制损伤累积导致的边坡失稳。

In the process of mining,blasting,as a very common means,produces irreversible damage to the surrounding rock mass.Once the damage limit of the rock mass is exceeded,the slope instability will be caused and serious safety accidents will be caused.Through acoustic testing technique,the damage variable is defined with acoustic wave velocity as the medium,which is used to describe the damage degree of rock.The cumulative effect of blasting damage is tested in the field,and a damage model considering the cumulative effect is established based on the field measured results.The model is developed and introduced into FLAC numerical simulation software,the stability of mine slope under continuous blasting is analyzed,and the reinforcement scheme is put forward.The results show that:①With the increase of blasting times,the internal damage degree of rock mass increases gradually,and finally reaches complete failure in the form of sudden surge;②By fitting the relationship between damage variable and blasting times and blasting charge in the test process,it is considered that the growth of damage variable is proportional to the exponential relationship of blasting times,and is proportional to the 0.5 square of blasting charge;③The stability control method of slope under frequent blasting is analyzed,and the proposed reinforcement scheme is helpful to control the slope instability caused by damage accumulation.