缓岩石边坡爆破施工技术在陆域形成工程中的应用

Blasting construction technology of gentle rock slope for land formation

一般的硬质岩石边坡倾角较大,或者为垂直边坡。边坡开挖有预裂爆破和光面爆破等形式,炮孔中心线与边坡线重合,施工较为简便。但对于软岩或风化程度较高的岩石边坡,为保证边坡的稳定,边坡倾角较小,要做到炮孔中心线与边坡线重合,施工不方便,难度较大。因此,对软岩、风化程度较高的缓岩石边坡,采用阶梯式垂直炮孔加孔底柔性垫层弱松动控制爆破的施工方法。该方法易于定位,钻孔效率高,工期较短,成本低。设置柔性垫层的目的是既将上部岩石破碎又不造成下部边坡的破坏。惠州港荃湾煤炭码头工程采取阶梯式垂直钻孔加孔底柔性垫层的爆破方法,成功开挖了73 000 m^2的边坡。

Usually,the slope of the hard rock is steep,or even vertical.The slope excavation method is pre-split blasting or smooth blasting.The center line of the borehole coincides with the slope line,and the construction is relatively simple.But for the soft rock or weathered rock slope,to ensure the stability of slope,the slope angle is smaller.It is difficult to make the center line of the borehole coincides with the slope line,so it is difficult to construct.For the soft rock or weathered rock,the construction method of controlled blasting with staged vertical borehole and flexible cushion is adopted,which is characterized by easy positioning,efficient drilling,short construction period and low cost.The purpose of setting flexible cushion on the bottom is to crush the upper rock without damaging the lower slope.By the method,73 000 m 2 slope of Quanwan coal wharf project in Huizhou Port was successfully excavated.