锡矿山锑矿围岩分级及锚喷支护实践研究

Study on the classification of surrounding rock and the technology of support by rockbolt and shotcrete in Xikuangshan antimony mine

锡矿山锑矿田矿床赋存于硅化灰岩中,呈缓倾斜似层状产出,上盘不稳固,矿体与下盘稳固,应用空场法回采矿体,嗣后一次充填处理采空区的两步回采方法。以往巷道采用料石或混凝土支护,采场顶板留0.8～1.2m的矿石护顶。为了节省巷道支护费用,加快支护速度,提高采场开采回采率,根据矿床围岩的岩体结构、岩性以及开挖体的大小、几何形态、开挖方式把围岩分成五级,针对不同级别的围岩选择合适的锚喷支护类型和设计参数。生产实践表明,采用锚杆喷射混凝土支护巷道较料石支护节省40%的费用,同时提高了掘进速度;采场采用锚杆喷射混凝土支护替代矿石护顶层,可提高开采回采率5%以上。取得了较好的安全技术和经济效果。

The deposit of the Xikuangshan antimony ore field lies in the silicified limestone and is output in a gently inclined way,layer by layer.Its hanging side is not solid and the ore body is firmed with the heading side.The ore body is firstly processed by applying the open-stope method and subsequently the two-step processing method is adopted for filling and handling the mined-out area.In the past,the laneway was usually supported with dressed stones or concrete and an ore canopy guard of 0.8～1.2mthickness was reserved in the stope roof.In order to save the laneway support expense,to accelerate the support speed and to increase the rate of mining recovery under the stope,the surrounding rocks have been classified into five levels according to the different rock structures/characters of the surrounding rocks of the deposit,the sizes/geometrical morphologies of the excavation bodies,as well as the excavation methods.The suitable boltshotcrete support types and design parameters shall be selected for different levels of surrounding rocks.The production practice shows that the application of the bolt-shotcrete support laneway,compared with that of the dressed-stone support laneway,will save 40% of expenditures and improve the advance rate;the replacement of the ore canopy guard with the bolt-shotcrete support under the stope will increase the rate of mining recovery by 5%.And better safety technologies and economic effects have been obtained at the same time.