Implementasi Shotcrete pada Heading Terowongan Batuan Lemah di Underground Kencana
Bibliographic record
Abstract
Abstrak. PT Nusa Halmahera Minerals merupakan salah satu perusahaan penambangan di wilayah Kabupaten Maluku Utara, yang melakukan penambangan bijih emas dengan metode underhand cut and fill dan sublevel stoping. Sistem penyangga menjadi sebuah komponen penting dalam metode penambangan tersebut agar proses penambangan dapat berjalan sesuai dengan rencana. Shortcrete merupakan salah satu sistem penyangga yang sering digunakan pada penambangan bawah tanah. Penelitian membahas tentang analisis kebutuhan shortcrete yang diperlukan untuk menyangga massa batuan disekitar lubang bukaan bawah tanah dengan kategori lemah. Proses analisis dilakukan dengan menggunakan metode klasifikasi Q-System, Bieniawski dan juga pengukuran data deformasi aktual di lapangan. Melalui bantuan pemodelan software di dapatkan model kestabilan dari masing-masing klasifikasi. Setelah didapatkan model kestabilan selanjutnya di tentukan jenis-jenis kebutuhan penyangga yang akan digunakan. Berdasarkan rekomendasi Bieniawski (1989) dibutuhkan kombinasi shotcrete dan wire mesh yang diaplikasikan pada dinding dengan ketebalan 9cm di area Section 1 dan 3, 5cm pada Section 2, sedangkan menurut Q-System penggunaan shotcrete dengan ketebalan 9cm. Hasil rekomendasi pada area heading memiliki nilai aman, dengan faktor keamanan sebesar 1,9 untuk Bieniawski dan Q-System, serta 1,6 untuk kondisi aktual. Hasil validasi alat geotechnic monitoring lidar menunjukkan bahwa pergerakan pada area left Wall dan left shoulder yaitu 9,135 mm dan 10,845mm sehingga digolongkan ke dalam kriteria relatif stabil. Abstract. PT Nusa Halmahera Minerals is a mining company in North Maluku Regency that mines gold ore using underhand cut and fill and sublevel stoping methods. Support systems are a crucial component of these mining methods, ensuring the process runs according to plan. Shortcrete is one support system frequently used in underground mining. This study analyzes the need for shortcrete to support the rock mass around weak underground openings. The analysis was conducted using the Q-System classification method and Bieniawski's method, along with actual field deformation data measurements. Through software modeling, stability models were obtained for each classification. Once the stability models were obtained, the types of support required were determined. Based on Bieniawski's (1989) recommendations, a combination of shotcrete and wire mesh was applied to the Walls with a thickness of 9 cm in Sections 1 and 3, and 5 cm in Section 2. The Q-System recommended using shotcrete with a thickness of 9 cm. The recommended heading results are considered safe, with a safety factor of 1.9 for Bieniawski and Q-System, and 1.6 for the actual conditions. Validation of the lidar geotechnical monitoring tool shows that the movement in the left Wall and left shoulder areas is 9,135 mm and 10,845 mm, respectively, thus categorizing them as relatively stable.
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How this classification was reachedexpand
Full frame distilled prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. Learned from the 10,348 direct Codex labels and 10,348 direct Gemma labels. Candidate is the union of thresholded teacher heads; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels or direct frontier model labels.
Codex and Gemma teacher scores by category
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.001 | 0.000 |
| Meta-epidemiology (narrow) | 0.001 | 0.001 |
| Meta-epidemiology (broad) | 0.001 | 0.001 |
| Bibliometrics | 0.001 | 0.001 |
| Science and technology studies | 0.001 | 0.000 |
| Scholarly communication | 0.001 | 0.001 |
| Open science | 0.001 | 0.000 |
| Research integrity | 0.000 | 0.001 |
| Insufficient payload (model declined to judge) | 0.000 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one teacher head, not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".