PROBABILISTIC ANALYSIS OF SCATTERING EFFECTS OF NONEL DETONATOR IGNITION TIME TO OPTIMIZE EXPLOSIVES LOADS WITH MINIMUM EXPLOSIVE VIBRATION IN UNDERGROUND MINES

• Main Author: Elisabeth Paulina Thenu, Paly
• Format: Theses
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/78336
• Institution: Institut Teknologi Bandung

PT Aneka Tambang Tbk Unit Bisnis Pertambangan Emas (UBPE) Pongkor uses NONEL initiation system in drilling and blasting operation. Error of initiation time using the NONEL system is inevitable and may lead to the possibility of several blast holes detonate simultaneously. This may result a high vibration magnitude. This study aims to observe the deviation time of detonation process using the NONEL system in underground blast operation and its relationship to the blast induces vibration. The detonator used was first divided into two segments namely detonator number 9-19 having long delay and 0-8 with short delay. Determination of the scattering percentage is carried out through three wave directions (longitudinal, transverse and vertical) and the peak vector sum (PVS) value. The study found that the detonator numbers of 9-19 produces a scattering percentage of 6.63%-6.86% while using detonators 0-8 produces a scattering percentage of 9.62%-15.69%. Scattering percentage was then used to see the range of possible detonation times for each segment. The results of probability analysis show that there is a possibility of overlapping detonation times for detonator numbers 11-14 and 4-7. Modification of explosive charge was carried out to predict the minimum vibration due to the possibility of overlapping detonation times. The predicted PPV were statistically compared to the measured PPV using root mean square error (RMSE).