GPR survey for subsurface utility mapping at Ahmedabad
Scope of Work:
GPR survey execution for mapping underground utilities to design the underpass preventing the damage to the pre-existing assets.
Location:
Ahmedabad, Gujarat, India.
Client:
IIM Ahmedabad
Equipment:
GSSI SIR-3000 equipped with 200 MHz and 400 MHz antenna
Summary:
The GPR survey has been carried out at three locations of proposed underpasses under 132 Feet Ring Road as connection between new and old IIM campus for IIM Ahmedabad. The total area scanned is around 1500 m2 in 9 patches on road and 12 patches on service road and footpaths. The scope of work includes the mapping of all possible underground utilities upto the depth of around 6-7 m using non-destructive Ground Penetrating Radar technology. The purpose of the project is to plan the execution of proposed underpasses project and prevent the damage to the existing utilities during the construction phase of same. The purpose of the survey was to map all the underground utilities viz. cables, water lines, gas lines, sewer line etc. upto the depth of 5-6 m using non-destructive technology. The whole data is collected in nine patches, each of dimension approximately 10 m X 11 m. Numerous parallel profiles have been collected across the width as well as along the length at an spacing of 1 m. Over all around 16 utility service lines along the road could be interpreted on the basis of repeating impressions in various profiles of patches. Interpreted utilities are categorised in different quality levels as per ASCE-3802 to define the tentative confidence level.