Analisis Penentuan Optimum Intershot Delay Timing dengan Signature Hole Analysis Methode dan Penentuan Isian Bahan Peledak Maksimum Per Delay untuk Mengontrol Getaran Tanah Hasil Peledakan Overburden pada PT Dnx Indonesia Jobsite Adaro, Tabalong Kalimantan Selatan

Abstract

Abstract. The research activities were carried out in Pit-CT1 and Pit-N1 at PT DNX Indonesia jobsite adaro, Tabalong, South Kalimantan. Blasting activities carried out at PT Adaro Indonesia could potentially disrupt the environment and settlements (Bata Village and Pertamina Tank). So a control of ground vibration is very necessary to avoid environmental issues based on the Indonesian National Standard 7571: 2010. In accordance with these regulations, Pit-CT1 and Pit-N1 have a ground vibration standard stated in PVS (Peak Vector Sum) of 2 mm/s. The method used in ground vibration control is by the signature hole analysis method using electronic detonators.The signature hole method is a method that analyzes the waves produced by blasting one shot hole. These waves will be simulated at each blasting wave with the Signature hole Analysis (SHA). Based on the results of the Signature hole Analysis (SHA) simulation, the optimum configuration delay  for the Pit-CT1 location production blasting activity is at the Inter Hole 62 ms delay  and the Inter Row delay  is 37 ms, while for the Pit-N1 location production hole blasting activity at Inter Hole delay  88 ms and Inter Row delay  53 ms with decreasing ground vibration value (PVS) an average of 34.66%. From the results of the ground vibration data of five signature holes at each location and production hole ground vibration data, the equation of the relationship between PPV and the scaled distance (SD) is PPV = 2.675.4 x (SD)^-1,625 for Pit CT1-Ds. Bata locations and PPV = 1.471.2 x (SD)^-1,379 for Pit CT1-Pertamina Tank locations. Whereas Pit Blasting N1-Ds Bata locations are PPV = 3.330.4 x (SD)^-1.69 and Pit N1-Pertamina Tank locations is PPV = 3.500.2 x (SD)^-1.704. Based on the equation of the relationship formula between PPV and SD obtained, maximum instantaneous charge the blasting locations Pit CT1-Pertamina tank and Pit CT1-Ds. Bata can be increased by 20.98% and 37.02%. As for the blasting locations Pit N1–Pertamina Tank and Pit N1–Ds. Bata, maximum instantaneous charge can be increased by 17.84% and 30.01%.

Keywords: Ground Vibration, Peak Vector Sum (PVS), Signature hole Analysis (SHA).

 

Abstrak. Kegiatan penelitian dilakukan di Pit-CT1 dan Pit-N1 pada PT DNX Indonesia jobsite adaro, Tabalong, Kalimantan Selatan. Kegiatan peledakan yang dilakukan di PT Adaro Indonesia dapat berpotensi mengganggu lingkungan dan pemukiman penduduk (Desa Bata serta Tangki Pertamina). Maka suatu kontrol getaran tanah sangat perlu dilakukan untuk menghindari isu lingkungan berdasarkan Standar Nasional Indonesia 7571:2010. Sesuai peraturan tersebut, Pit-CT1 dan Pit-N1 memiliki standar getaran tanah yang dinyatakan dalam PVS (Peak Vector Sum) sebesar 2 mm/s. Metode yang digunakan dalam kontrol getaran tanah ini adalah dengan metode signature hole analysis menggunakan detonator elektronik. Metode signature hole adalah metode yang menganalisis gelombang yang dihasilkan dari peledakan satu lubang tembak. Gelombang tersebut akan disimulasikan pada tiap-tiap gelombang peledakan dengan signature hole analysis (SHA).  Berdasarkan hasil simulasi signature hole analysis (SHA) maka didapatkan delay  configurasi yang optimum untuk kegiatan peledakan lubang produksi lokasi Pit-CT1 adalah pada inter hole delay  62 ms dan Inter row delay   37 ms, sedangkan untuk kegiatan peledakan lubang produksi lokasi Pit-N1 pada inter hole delay  88 ms dan inter row delay  53 ms dengan penurunan nilai getaran tanah (PVS) rata-rata sebesar 34,66%. Dari hasil data getaran tanah lima lubang signature pada tiap lokasi dan data getaran tanah lubang produksi, didapatkan persamaan rumus hubungan antara PPV dan scaled distance (SD) yaitu PPV = 2.675,4 x (SD)^-1,625 untuk lokasi Pit CT1–Ds bata dan PPV = 1.471,2 x (SD)^-1,379 untuk lokasi Pit CT1–Tangki Pertamina. Sedangkan untuk Lokasi peledakan Pit N1 – Ds Bata yaitu PPV = 3.330,4 x (SD)^-1,69 dan lokasi Pit N1–Tangki Pertamina yaitu PPV = 3.500,2 x (SD)^-1,704. Berdasarkan persamaan rumus hubungan antara PPV dan SD yang didapat, isian bahan peledak maksimum per delay  lokasi peledakan Pit CT1–Tangki Pertamina dan Pit CT1–Ds. Bata dapat  ditingkatkan sebanyak 20,98% dan 37,02%. Sedangkan untuk lokasi peledakan Pit N1–Tangki Pertamina dan Pit N1–Ds. Bata, isian bahan peledak per delay  dapat ditingkatkan sebanyak 17,84% dan 30,01%.

Kata Kunci: Getaran Tanah, Peak Vector Sum (PVS), Signature hole Analysis (SHA).