MINIMALISASI OVERBREAK DAN UNDERBREAK MELALUI PEMODELAN PREDIKTIF DAN OPTIMASI PELEDAKAN PT FREEPORT INDONESIA

Rochsyid Anggara; Bantar Tyas Suksmawati Rukmana; Rayhan Naufal Pratama; Jeffryson Munsaki Rumbewas

doi:10.30556/jtmb.Vol21.No3.2025.1719

Penulis

Rochsyid Anggara Prodi Teknik Pertambangan Universitas Pembangunan Nasional Veteran Yogyakarta
Bantar Tyas Suksmawati Rukmana
Rayhan Naufal Pratama
Jeffryson Munsaki Rumbewas

DOI:

https://doi.org/10.30556/jtmb.Vol21.No3.2025.1719

Kata Kunci:

overbreak, powder factor, prediksi, underbreak

Abstrak

Peledakan pada pengembangan bukaan tambang bawah tanah di Tambang Kucing Liar (KL) PT Freeport Indonesia (PTFI) berpotensi menimbulkan overbreak dan underbreak. Evaluasi peledakan di November 2024 menunjukkan bahwa pada beberapa heading, nilai deviasi geometri melebihi batas toleransi perusahaan sebesar 10%, sehingga diperlukan optimasi parameter peledakan. Penelitian ini bertujuan untuk mengendalikan overbreak–underbreak melalui pengembangan model prediktif berbasis parameter geoteknik dan peledakan. Analisis dilakukan menggunakan Multiple Regression Analysis (MRA) terhadap 53 data peledakan dengan variabel Rock Mass Classification (Q-Value), Perimeter Powder Factor (PPF), dan Confinement Factor (C). Kebaruan penelitian ini terletak pada integrasi model regresi multivariat berbasis data operasional dengan simulasi Monte Carlo untuk menghasilkan optimasi parameter peledakan secara probabilistik dan aplikatif. Model regresi selanjutnya digunakan dalam simulasi Monte Carlo sebanyak 5.000 iterasi. Hasil menunjukkan bahwa overbreak dipengaruhi secara signifikan oleh Q-Value, PPF dan C (R² = 0,693), sedangkan underbreak didominasi oleh Q-Value (R² = 0,470). Simulasi Monte Carlo menghasilkan nilai rata-rata overbreak sebesar 7,41% dan underbreak sebesar 5,37%, keduanya berada di bawah batas toleransi perusahaan.

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