DIGGING FORCE ANALYSIS OF LOOSE MATERIAL USING LABORATORY-SCALE EXCAVATOR

• Main Author: Syaoqi Najib, M.
• Format: Theses
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/77157
• Institution: Institut Teknologi Bandung

An excavator is heavy equipment used for excavating materials in the civil construction projects and mining industries. Optimum excavation can reduce excavation costs and the negative effects of excavation activities on the equipment. The forces during excavation (digging force) may vary depending on the condition of the material, the digging position, and the diameter of the hydraulic cylinder. This research aims to study the required digging force to unload material by measuring hydraulic pump pressure on laboratory-scale excavator components (arm & tooth and with bucket volume ± 4 liters). The test was carried out on loose andesite materials from various attack angles (40°, 50°, 60°, 70°, and 80°). Calibration with a load cell is required to link the hydraulic pump pressure data with the force data shown by the load cell during the loading activities, assuming that the excavator’s acting force is equal to the force on the load cell. Data processing is carried out by linear regression method to correlate hydraulic pump pressure data with load cell calibration loading data. Another approach is used to calculate the force (resistive force) during excavation with the Fundamental Earth- Moving Equation and numerical simulation using PFC2D to predict the digging force. The results show that the ratio of experiment and analytical forces are in the same trend line, with ratio between the average force are 0.8 for initial digging 400, 1.14 for 500, 0.68 for 600, 1.18 for 700, and 0.96 for 800. Then the force ratio between experiment test and numerical simulations shows that at certain initial digging, the force still show relatively the same trendline, with the average force values at the initial angle of the 400 experiment test nail with the initial digging of 450 numerical is 0.84 and the initial angle of 800 experiment test with the digging of 900 numerical is 1.58. The specific energy of experiment test is directly proportional to the digging force, by the lowest specific energy is 0.03 MJ/m3 with an initial digging of 60°.