Effect Analysis of the Selection Method for Calculating Time of Concentration and Rainfall Plans for The Design of Open Channels in Open Pit Mining.
Tedy Agung Cahyadi(a) , Angelina Metta(b), Sudaryanto(a), Charles Andrianto(c), Suyono(a), Eddy Winarno(a)
(a) Lecturer of Universitas Pembangunan Nasional Yogyakarta, Indonesia. Jl. SWK 104, Condongcatur, Depok, Kecamatan Depok, Ngropoh, Condongcatur, Kec. Depok, Kabupaten Sleman, Daerah Istimewa Yogyakarta 55283
(b) Student of Universitas Pembangunan Nasional Yogyakarta, Indonesia. Jl. SWK 104, Condongcatur, Depok, Kecamatan Depok, Ngropoh, Condongcatur, Kec. Depok, Kabupaten Sleman, Daerah Istimewa Yogyakarta 55283
(c) Senior Hydrogeology engineer PT. ANTAM UBPN Pomalaa, Kolaka, Sulawesi Utara
Abstract
In designing the dimensions of the open channel in open pit mining, there are factors that should be considered including rainfall intensity, runoff coefficient, and catchment area. These three main factors will determine the amount of runoff water entering the pit and affect the dimensions of the open channels that are expected to handle the runoff water discharge. This research aims to analyse the effect of selection method for calculating time of concentration and rainfall plans for the dimensions of the drainage that are needed to handle the runoff water. This research uses primary data from direct observation on the field and secondary data based on rainfall data from BMKG station. Izzard, William, and field observation method are used to determine the time of concentration, while maximum, average, and minimum method are used to determine the rainfall plans. Both factors are greatly influence the value of rainfall intensity. The results of this research are open channel (drainage) dimensions which are calculated based on rainfall intensity which is first calculated using the analysis of several methods. It is expected that the results are appropriate and in accordance with the needs of the mine openings so that mining operations can run smoothly.
Keywords: Open Channel, Time of Concentration, Rainfall plans, Rainfall Intensity, drainage system, Izzard Method, Williams Method
Topic: International Symposium of Civil, Environmental, and Infrastructure Engineering