Kajian Geoteknik Untuk Desain Pit Tambang Batugamping Di Daerah Karang Dawa, Kecamatan Margasari, Kabupaten Tegal, Jawa Tengah

Geotechnical Studies For The Design Of The Limestone Mine Pit In The Area Of The Reef Dawa, Kecamatan Tegal Regency Margasari, Central Java

Abstract

Location of research situated in the village Karangdawa, district Margasari, Tegal Regency,

Central Java. The location of the research is the exploration Licences PT.

Indocement Tunggal Prakarsa Tbk., with commodities limestone. This research is aimed at

mengetahuikualitas, batugampingserta reserves and resources geotechnical model based on

the geological model. Geotechnical models also determined based on the model of rockmass used

slope stability analysis as a model to design the mine pit. The methods used

in this research include field work in the form of observation of outcrops of rocks and

develop the sample, as well as laboratory analysis in the form of analysis of petrographic analysis and XRF

using the sample surface, analysis of physical and mechanical properties of the rock mass classification, as well as

rocks based on Geological Strenght Index (GSI) uses a secondary data in the form of core data

drilling. Analysis of the stability of slopes in this study using the method of limit equilibrium

(limit equilibrium method). Interpretation and correlation of data indicating that the drilling core location

stratigraphic research is composed by three units of rock: limestone, batulempung, as well as

sandstones. XRF analysis results and modeling geology suggests the quality of limestone meet

cement raw material standards as to the amount of 13,180,000 tons of limestone resources. The geometry of the slope resulting from the analysis of the stability of slopes of which are: single slope height of 10 meters,

the angle of slope of a single 80-degree slope, the slope of the overall 48 degrees, 50 degrees, 60 degrees, 54

degrees, the wide level of 8.31 meters. Limestone reserves estimation is determined only on the basis of

consideration of the mine pit design and ultimate pit limit which is limited by the territory of IUP. Backup

tertambang (mineable reserve) limestone amounted to 7,477,000 tonnes.