Analisis potensial longsoran pada lereng elevasi 690 meter, PIT South Osela, Site Babakan, PT. J Resources Bolaang Mongondow
P PT J Resources menambang emas dengan sistem penambangan terbuka. Saat ini penambangan pada open pit south osela telah mencapai elevasi 675 meter. Perlu adanya analisis potensi longsoran pada lereng yang terbentuk agar operasional tambang tidak terganggu. Penelitian ini bertujuan mengukur seberapa besar potensi longsoran secara stereografis pada lereng elevasi 690 meter. Pun begitu untuk mengetahui jenis dari potensi longsoran yang kemudian dicari solusinya.Data primer dikumpulkan melalui window mapping, dimana semua struktur yang tersingkap pada permukaan lereng direcord (dengan satuan luasan) dan dibagi kedalam beberapa segmen. Panjang lereng yang diteliti ialah 180 meter, yang dibagi kedalam 18 segmen. Adapun standard window mapping menggunakan standard ISRM 1981 yang kemudian dikonversi menjadi klasifikasi massa batuan RMR Bieniawski.Data pemetaan diolah menggunakan analisa stereografis dengan software Dips dari Rocscience untuk memperoleh orientasi bidang lemah, kemudian ditinjau pada kriteria keruntuhan Hoek dan Brown untuk memperoleh sudut gesek dalam batuan dengan bantuan software Roclab dari Rocscience. Mengingat parameter analisa kinematik atau stereografis ialah orientasi lereng, orientasi bidang lemah dan sudut gesek dalam.Hasil penelitian menunjukkan 4 dari 18 segmen berpotensi longsoran diantaranya segmen G, segmen I, segmen J dan segmen Q. Di mana segmen G, segmen I dan segmen J berpotensi longsoran baji, sementara segmen Q berpotensi longsoran guling.
P PT J Resources mines gold with an open pit system. Currently, mining at the Open Pit South Osela has reached the elevation of 675 meter. It is necessary to analyze the avalanche potential on the slope that is formed so that mining operations are not disturbed. This study aims to measure how big is the avalanche potential stereographically on the slope of elevation 690 meter. Even so, to know the type of avalanche potential which then sought the solution.Primary data is collected through window mapping, where all the structures exposed on the slope surface are reconstructed (by unit area) and divided into several segments. The length of the slopes studied is 180 meters, which is divided into 18 segments. The standard window mapping using the ISRM standard 1981 which later converted into the rock mass classification of RMR Bieniawski.Mapping data is processed using stereographic analysis with Dips software from Rocscience to obtain discontinuities orientation, which previously reviewed on Hoek and Brown Failure Criterion to obtain friction angle in rocks with the help of Roclab software from Rocscience. Given the parameters of kinematic or stereographic analysis are the orientation of the slope, the orientation of the discontinuities and the internal friction angle.The results showed, 4 out of 18 segments are potentially avalanche, which are G Segment, I Segment, J Segment and Q Segment. Where, G Segment, I Segment and J Segment are potentially wedge fail, whereas toppling failure is potential to occur in Q Segment.