Evaluasi Massa Batuan Terowongan Eksplorasi Uranium Eko-Remaja, Kalan, Kalimantan Barat

Dhatu Kamajati; Heri Syaeful; Mirna Berliana Garwan

doi:10.55981/eksplorium.2016.3110

Evaluasi Massa Batuan Terowongan Eksplorasi Uranium Eko-Remaja, Kalan, Kalimantan Barat

Dhatu Kamajati, Heri Syaeful, Mirna Berliana Garwan

DOI: http://dx.doi.org/10.55981/eksplorium.2016.3110

Abstract

ABSTRAK

Terowongan eksplorasi uranium Eko Remaja, Kalan, Kalimantan Barat merupakan salah satu sarana penelitian cebakan uranium yang sangat penting. Terowongan ini dibangun tahun 1980 dengan panjang 618 meter dan menembus Bukit Eko di kedua sisinya. Batuan di terowongan ini relatif kompak, tetapi memiliki zona lemah di beberapa bagiannya. Penyanggaan merupakan metode yang digunakan untuk menanggulangi keruntuhan tanah dan batuan yang terjadi pada zona lemah di terowongan. Pemasangan penyangga yang selama ini dilakukan berdasarkan pola keruntuhan yang terjadi pada saat pembukaan terowongan tanpa melalui studi khusus menyangkut karakterisasi massa batuan dan kebutuhan sistem penyangga. Penelitian ini dilakukan untuk mengevaluasi tingkat keselamatan terowongan Eko-Remaja dan kesesuaian lokasi penyangga. Evaluasi dilakukan dengan membandingkan karakteristik massa batuan menggunakan metode Rock Mass Rating (RMR) antara lokasi penyangga batuan terpasang dan lokasi penyangga batuan tidak terpasang. Berdasarkan hasil analisis, nilai RMR pada lokasi terpasang penyangga diklasifikasikan ke dalam kelas IV atau batuan buruk. Sementara itu, di lokasi tidak terpasang penyangga batuan diklasifikasikan ke dalam kelas II atau batuan baik. Berdasarkan korelasi antara hasil perhitungan RMR dengan roof span terowongan Eko-Remaja disimpulkan bahwa posisi penyanggaan terowongan yang diwakili oleh lokasi pengamatan pada kedalaman 38 m, 73 m, dan 165 m sudah sesuai dengan sistem karakterisasi massa batuan menggunakan metode RMR.

ABSTRACT

Eko-Remaja uranium exploration tunnel, Kalan, West Kalimantan is one of the important facilities for uranium deposit research. The tunnel was built in 1980 with a length of 618 meters penetrating Eko Hill on both sides. The rock inside the tunnel is relatively compact, but it has weak zones in some area. Ground supporting is a method used to overcome the soil and rock collapses which occurred in the tunnel weak zones. Installation of ground supporting system throughout the recent time based on the soil collapse pattern, which occurred when the tunnel opened without any specific study related to rock mass characterization and the requirement of ground support system. This research conducted to evaluate the safety level of Eko-Remaja tunnel and the suitability of ground support location. The evaluation performed by comparing the rock mass characteristics using Rock Mass Rating (RMR) method between the installed rock support and uninstalled rock support locations. Based on the analysis result, RMR value on the installed ground support is classified as class IV or poor rock. Meanwhile, on uninstalled location, the rock is classified as class II or fair rock. Based on the correlation between RMR calculation result and Eko-Remaja tunnel roof span, it is concluded that tunnel ground supports position which are represented by observation location on 38 m, 73 m, and 165 m depth are suitable with rock mass characterization system using RMR method.

Keywords

evaluasi; massa; batuan; terowongan; penyanggaan; eksplorasi; uranium

Full Text:

PDF (Bahasa Indonesia)

References

[1] A. Zaenal, “Beton Cetak Bertulang sebagai Alternatif Pengganti Kayu Penyangga di Terowongan Eksplorasi U Eko Remaja Kal-Bar,” Prosiding Seminar Geologi Nuklir dan Sumberdaya Tambang, 2006.

[2] Z. T. Bieniawski, Engineering Rock Mass Classification: A Complete Manual for Engineers and Geologists in Mining, Civil, and Petroleum Engineering. New York: John Wiley & Sons, Inc., 1989.

[3] F. Ferrari, T. Apuani, and G. P. Giani, “Rock Mass Rating Spatial Estimation by Geostatistical Analysis,” Int. J. Rock Mech. Min. Sci., vol. 70, pp. 162–176, 2014.

[4] S. S. D. P. Kanungo and S. Kumar, “Rock Mass Classification and Slope Stability Assessment of Road Cut Slopes in Garhwal Himalaya, India,” 2012.

[5] A. Benato and P. Oreste, “Prediction of Penetration Per Revolution in TBM Tunneling as A Function of Intact Rock and Rock Mass Characteristics,” Int. J. Rock Mech. Min. Sci., vol. 74, pp. 119–127, 2015.

[6] C. Chen and Y. Liu, “A Methodology for Evaluation and Classification of Rock Mass Quality on Tunnel Engineering,” vol. 22, pp. 377–387, 2007.

[7] S. Dochez, F. Laouafa, C. Franck, S. Guedon, M. Bost, and J. D. Amato, “Influence of Water on Rock Discontinuities and Stability of Rock Mass,” Procedia Earth Planet. Sci., vol. 7, pp. 219–222, 2013.

[8] H. Farhadian, H. Katibeh, P. Huggenberger, and C. Butscher, “Optimum Model Extent for Numerical Simulation of Tunnel Inflow in Fractured Rock,” Tunn. Undergr. Sp. Technol., vol. 60, pp. 21–29, 2016.

[9] L. Zhang, “Journal of Rock Mechanics and Geotechnical Engineering Determination and Applications of Rock Quality Designation (RQD),” vol. 8, pp. 389–397, 2016.

[10] A. Lowson, “Critical Assessment of RMR based Tunnel Design Practices: a Practical Engineer’s Approach,” in Rapid Excavation & Tunneling Conf., 2013.

[11] V. Nguyen and Q. Nguyen, “Analytical Solution for Estimating The Stand-Up Time of the Rock Mass Surrounding Tunnel,” Tunn. Undergr. Sp. Technol. Inc. Trenchless Technol. Res., vol. 47, pp. 10–15, 2015.

[12] S. R. Rahutomo, “Evaluasi Penyanggaan pada Terowongan Eksplorasi Tambang Uranium Eko-Remaja, Pusat Pengembangan Geologi Nuklir-BATAN, Kalimantan Barat,” Skripsi UPN “Veteran” Yogyakarta, 2013.

[13] N. Bilgin, H. Copur, and C. Balci, “Use of Schmidt Hammer with Special Reference to Strength Reduction Factor Related to Cleat Presence in A Coal Mine,” Int. J. Rock Mech. Min. Sci., vol. 84, pp. 25–33, 2016.

[14] R. Arwanto, “Respon Kuat Tekan Hammer Test dengan Compression Test pada Beton Normal dan Beton Paska Bakar,” Media Komun. Tek. Sipil, vol. 14, no. 1, pp. 85–94, 2006.

[15] H. S. Karyono, “Analisis Kontrol Tektonik pada Vein Mineralisasi di Bukit Eko, Kalan, Kalimantan Barat,” in Prosiding Pertemuan Ilmiah Tahunan ke-2 IAGI, 1991, pp. 115–128.

[16] I. Yilmaz and H. Sendir, “Correlation of Schmidt Hardness with Unconfined Compressive Strength and Young’s Modulus in Gypsum from Sivas (Turkey),” Eng. Geol., vol. 66, no. 3–4, pp. 211–219, 2002.

[17] H. Syaeful, “Analisis Karakteristik Massa Batuan di Sektor Lemajung, Kalan, Kalimantan Barat,” Eksplorium, vol. 36, no. 1, pp. 17–30, 2015.