露天矿山斜层状边坡削坡卸载爆破技术

Slope Cutting and Unloading Blasting Technology for Inclined Layered Slope in Open-pit Mine

为了改善尖山磷矿边坡削坡卸载爆破时因边坡自然裂隙、地质分层等非常复杂而无法取得理想效果的问题,根据磷矿边坡分层特点,结合预裂爆破和光面爆破2种技术的优点,将岩层间自然裂隙作为预裂缝实施边坡控制爆破,提出了临近边坡缓冲减振爆破技术。在临近开采平台临近永久边坡处布置2排缓冲孔和1排主爆孔,以自然裂隙为预裂缝,缓冲孔按照1/3的比例分段装药,中间填充1.5 m惰性充填料;主爆孔采用连续装药,逐孔起爆技术。该技术实施半年多,削坡后的边坡坡面光滑平整,有效保证了边坡安全,比常规预裂爆破节约了穿孔爆破费用和后期破碎费用近200万元,在加快边坡削坡卸载速度的同时,减小了对边坡的扰动和延缓了边坡的变化速率,有力保障了东采区边坡下方矿岩铲运持续进行,可为类似工程施工提供参考。

In order to improve the problem that the slope of Jianshan Phosphate Mine cannot achieve ideal effect due to the complicated natural fractures and geological stratification in slope cutting and unloading blasting,according to the stratification characteristics of phosphate rock slope,combining the advantages of pre-split blasting and smooth blasting,the natural crack between rock strata is used as pre-fracture to carry out controlled blasting of slope,and the vibration reduction blasting technology near the slope is put forward.Two rows of buffer holes and one row of main blasting holes are arranged near the permanent slope near the mining platform.Taking the natural cracks are as pre-cracks,the buffer holes are charged in sections according to 1/3 proportion,and 1.5 m inert filling is filled in the middle;the main blasting hole adopts continuous charging and hole by hole initiation technique.Since more than half a year of implementation,the slope surface after cutting is smooth and level,and the safety of the slope is ensured.Compared with the conventional pre-splitting blasting,the cost of nearly 2 million yuan perforation blasting and the cost of later crushing is saved.It not only speeds up the slope cutting unloading speed,but also reduces the disturbance to the slope and delays the change rate of the slope,which effectively guarantees the continuous mining and rock shoveling under the slope in the eastern mining area,and can provide reference for similar engineering construction.