FIELD EXPERIMENT FOR UNDERGROUND PIPE IDENTIFICATION USING ELECTROMAGNETIC INDUCTION METHOD AND SUPPORTED BY GROUND PENETRATING RADAR METHOD

• Main Author: Rizky Gunawan, Al
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/77573
• Institution: Institut Teknologi Bandung

Underground pipe mapping is crucial to prevent pipe leakage issues caused by civil construction projects involving soil excavation. This mapping can be accomplished using geophysical methods. One of the most employed methods is ground-penetrating radar (GPR), which allows for accurate pipe detection. There are other geophysical methods theoretically viable for pipe detection but are seldom utilized, such as electromagnetic induction (EMI). This study aims to assess the effectiveness of the EMI method in pipe detection while utilizing GPR as complementary data. The research took place within the premises of the Tirtawening Dago Pakar Regional Water Company (Perusahaan Daerah Air Minum/PDAM) in Bandung City, West Java. In this area, a water pipe is buried at a depth of 1.5 meters with a diameter of 0.3 meters. The EMI method employed the EM38-MK2 instrument and covered a 16 × 13- meter area with 1-meter spacing. Meanwhile, the GPR method utilized a GSSI 270 MHz device, conducting measurements along 10 tracks, each 10 meters in length, with 1-meter spacing. EMI measurements were varied in terms of configuration, coil separation, instrument height, and instrument orientation. The conductivity map of the vertical dipole mode (VDM) configuration, 1-meter coil separation, 0-meter instrument height, and parallel instrument orientation showed a negative anomaly pattern that depicted the location and direction of the pipe. Mapping susceptibility in each mode could not provide information about the pipe's location and direction. Conductivity mapping using the EMI method indicated the location and direction of the pipe towards the northwest. The same results were also indicated by the hyperbolic patterns in the GPR radargram. The consistency between EMI and GPR data proves that the EMI method can be applied for pipe detection.