Perancangan Desain Timbunan Batubara dan Pengaruhnya Terhadap Kestabilan Lereng di Sekitar ROM 4 Site DMP PT Cipta Kridatama

Abstract

The increase in coal production every month at PT Cipta Kridatama Dizamatra Powerindo site results in the need for additional ROMs to accommodate the coal production produced. ROM 4 as a new ROM has not yet known the bearing capacity of ROM base soil, maximum height of embankment, and slope stability analysis. Therefore, it is necessary to conduct a geotechnical study on the bearing capacity of the base soil and slope stability around ROM 4. This study aims to design a coal stockpile design, analyze the slope stability around ROM 4, compare FK values between static, dynamic, before, and after loading conditions. The methods used in the slope stability analysis are Bishop, Janbu, Morgenstern-Price, and Spencer methods. The test data used are coal content weight data of 1.10 g/cm3 and soil bearing capacity of 109 kPa or CBR of 40%. The results showed that the optimal design of ROM 4 coal embankment based on its soil bearing capacity has a maximum height of 17 m, an embankment slope angle of 36°, and a capacity of 511,594.44 tons. The FK value of the slope around ROM 4 both before and after loading under static conditions is greater than 1.3 and dynamic conditions are greater than 1.1. The method that produces the smallest FK value is Janbu. Comparison of FK values of each LEM method, in static conditions is greater than dynamic conditions. While the comparison of FK values before loading is greater than after loading. The FK value of the slope around ROM 4 is declared safe because it is in accordance with the standards set by the Minister of Energy and Mineral Resources Decree No. 1827/K/30/MEM/2018.