【摘要】：大紅山淺部熔巖鐵礦位于礦區(qū)曼崗河以東,礦體埋藏較淺,適合采用沿岸坡露天開采。設計的采場坡頂線標高為1165m,坡底線標高為730m,垂直高度430米。通過對比類似露采礦山的開采經驗設定開采臺階坡面角為65°,邊坡的最終坡角為46°。采場現(xiàn)已開采至910平臺,為保證安全生產提高開采效益,需對采場邊坡進行穩(wěn)定性評估,在此基礎上進行開挖坡角的優(yōu)化,以提高礦山經濟利益。本文以巖體質量為基礎,在此基礎上根據(jù)CSMR法對邊坡的穩(wěn)定性進行定性評估,依據(jù)兩條典型剖面的地層分布情況,利用有限元強度折減軟件——Midas GTS NX模擬了邊坡在各開采階段的穩(wěn)定穩(wěn)定性系數(shù),對比兩條剖面最終的穩(wěn)定性系數(shù),取最小值作為采場邊坡的安全性系數(shù)。取得的主要成果和認識如下:1、根據(jù)邊坡巖體的巖性特征將采場巖體劃分為四個工程巖組:松散巖組、半堅硬沉積巖組、堅硬變質巖組、堅硬侵入巖組;將采場邊坡分為倆個區(qū)段,950平臺之上的片巖邊坡區(qū)段;950平臺之下的熔巖邊坡區(qū)段。2、統(tǒng)計分析采場主要巖體的節(jié)理裂隙,得出片巖邊坡巖體主要發(fā)育有四組優(yōu)勢結構面,其中J3節(jié)理不利于邊坡的穩(wěn)定;熔巖邊坡區(qū)段巖體發(fā)育倆組優(yōu)勢結構面,與邊坡呈反向分布,有利于邊坡的穩(wěn)定。3、依據(jù)采場巖體RMR評分值判斷采場巖體除砂巖外均為好巖體。采用CSMR法對采場邊坡的穩(wěn)定性進行分級,求得的最小CSMR值為61.9,據(jù)此將邊坡穩(wěn)定性等級定為ⅡI級穩(wěn)定,邊坡出現(xiàn)局部的掉塊以點狀加固為主。4、采用Hoek-Brown準則求取巖體力學強度參數(shù),利用有限元強度折減軟件——Midas GTS NX求取邊坡在各開采階段的穩(wěn)定性系數(shù)。5、根據(jù)潛在滑移面云圖知采場邊坡潛在滑移面為弧形,隨著開采深度的增加潛在滑移面下移,穩(wěn)定系數(shù)減小,采場的最終穩(wěn)定性系數(shù)介于1.34-1.44之間。6、對A36號剖面進行放大臺階坡面角模擬,求得的最終邊坡的穩(wěn)定性系數(shù)為1.21,滿足礦山安全生產,因此在采場的未開采區(qū)可以根據(jù)礦石的分布情況采取放大臺階坡面角的方式進行開采以提高開采效益。
[Abstract]:Dayongshan shallow lava iron deposit is located in the east of Mangang River, and the orebody is shallow buried, so it is suitable for open-pit mining along the coast slope. The elevation of the slope top line is 1165 m, the bottom line elevation is 730 m, and the vertical height is 430 m. By comparing the mining experience of similar open mining mines, the slope angle of mining step is 65 擄and the final slope angle of slope is 46 擄. The stope has been mined to 910 platform. In order to ensure safe production and improve mining efficiency, it is necessary to evaluate the stability of stope slope, and on this basis to optimize the excavation slope angle in order to improve the economic benefits of the mine. Based on the quality of rock mass, the stability of slope is evaluated qualitatively by CSMR method, and the stratigraphic distribution of two typical sections is analyzed. Using the finite element strength reduction software Midas GTS NX, the stability coefficient of the slope in each mining stage is simulated, the final stability coefficient of the two sections is compared, and the minimum value is taken as the safety coefficient of the stope slope. According to the lithologic characteristics of the slope rock mass, the stope rock mass is divided into four engineering rock groups: loose rock group, semi-hard sedimentary rock group, hard metamorphic rock group, hard intrusive rock group; The stope slope is divided into two sections, the schist slope section above the platform of Kui 950, and the section of lava slope below the platform of platform No. 950. By statistical analysis of the joints and fractures of the main rock mass in the stope, it is concluded that there are four groups of dominant structural planes mainly developed in the schist slope rock mass. J3 joints are not conducive to the stability of the slope, and two groups of dominant structural planes are developed in the section of the lava slope, which is opposite to the slope, which is favorable to the stability of the slope. According to the RMR score of the stope rock mass, it is judged that the stope rock mass is a good rock mass except sandstone. The stability of stope slope is classified by CSMR method, and the minimum CSMR value is 61.9. According to this, the slope stability grade is classified as 鈪，

本文編號：2210803