地应力影响下立井爆破扩掘岩石块度形态  

Rock Size Shape of Vertical Shaft Blasting Excavation under theInfluence of in-situ Stress

作　　者：郭子洋 唐海 袁刚 马谕杰 张肖雨 黄靖龙[2] GUO Zi-yang;TANG Hai;YUAN Gang;MA Yu-jie;ZHANG Xiao-yu;HUANG Jing-long(School of Resources,Environment and Safety Engineering,Hunan University of Science and Technology,Xiangtan 411201,China;Engineering Research Center of Advanced Mining Equipment,Ministry of Education,Hunan University of Science and Technology,Xiangtan 411201,China)

机构地区：[1]湖南科技大学资源环境与安全工程学院,湘潭411201 [2]湖南科技大学深海深地矿产资源开发技术与装备教育部工程研究中心,湘潭411201

出　　处：《科学技术与工程》2024年第30期12909-12919,共11页Science Technology and Engineering

基　　金：湖南省教育厅资助科研项目(20A196)。

摘　　要：为获取不同地应力下的爆破岩石块度信息,避免在立井正向爆破扩掘中出现爆后岩石块度过大的现象,通过有限元ANSYS/LS-DYNA建立了立井计算模型,研究了岩石碎片面积分布规律,分析了不同类型裂隙面的形成效果;最后对岩体应力状态进行分析,判定对应裂隙面的形成效果,明确大块岩石的形成位置,并在此基础上提出爆破方案设计建议。结果表明:随着地应力的不断增加,碎片面积分布区间变广,主要分布区间由0~300 cm^(2)逐渐向300~900 cm^(2)过渡,且爆后岩块向不规则体发展;当地应力超过5 MPa时,爆破会产生1500~1800 cm^(2)的碎片,接近允许最大碎片面积1736 cm^(2),产生的爆破岩石块可能堵塞导井;靠近设计开挖面的岩体底部其垂向应力较大,水平裂隙面形成受阻,爆破易产生大块岩石;靠近开挖岩体上表面处的岩体其垂向应力较小,容易形成水平裂隙面。可见,在设计立井爆破扩掘方案时,应考虑在靠近设计开挖面岩体的底部加强装药,并按照从扩掘岩体上部至下部的顺序,依次起爆相同装药高度的炸药,改变岩体应力状态,减小爆后岩石块度,避免爆生岩块堵塞导井。In order to obtain the information of blasting rock size under different geostresses and avoid the phenomenon of excessive rock size after blasting in vertical shaft forward blasting expansion,a vertical shaft calculation model was established by ANSYS/LS-DYNA,the distribution law of rock debris area was studied,and the formation effects of different types of fracture surfaces were analyzed.Finally,the stress state of the rock mass was analyzed,the formation effect of the corresponding fracture surface was determined,and the formation position of the large rock was clarified.On this basis,the blasting scheme design suggestions were put forward.The results show that with the continuous increase of in-situ stress,the distribution interval of debris area becomes wider,and the main distribution interval gradually transitions from 0~300 cm^(2) to 300~900 cm^(2),and the rock block develops to an irregular body after blasting.When the local stress exceeds 5 MPa,the blasting will produce 1500~1800 cm^(2) debris,which is close to the allowed maximum debris area of 1736 cm^(2),and the generated blasting rocks may block the pilot well.The vertical stress at the bottom of the rock mass close to the design excavation surface is large,the formation of horizontal fracture surface is blocked,and the blasting is easy to produce large rocks.The vertical stress of the rock mass near the upper surface of the excavated rock mass is small,and the horizontal fracture surface is easy to form.It is concluded that when designing the scheme of vertical shaft blasting expansion,it should be considered to strengthen the charge at the bottom of the rock mass close to the design excavation surface,and according to the order from the upper to the lower part of the expanded rock mass,detonate the explosives of the same charge height in turn,change the stress state of the rock mass,reduce the rock mass degree after blasting,and avoid the blockage of the pilot well by the exploded rock block.

关 键 词：扩掘爆破 岩石块度 导井 地应力 数值模拟 

分 类 号：TD235[矿业工程—矿井建设]