Knowledge of ground conditions is key

Inadequate ground surveys can result in erroneous choice of foundation engineering solutions, incorrect design of foundations, inappropriate and Dangerous implementation of ground work as well as damage to both neighbouring buildings and the new building itself. It can also lead to oversized and therefore unnecessarily costly foundations.

NGI
NGI acquired an advanced Sonic drilling rig in 2017. This is perfect for sampling in stiff soil conditions, such as moraine, and it provides continuous samples from the soil layers. The rig is the first of its kind in Norway, and has already been used for soil investigations along the planned railway Ringeriksbanen north-west of Oslo, environmental sampling of contaminated ground, as well as sampling down to 12 metres in an embankment dam which had leaks.
 

Combination of geophysical and traditional field surveys

Field surveys include field inspections with visual inspection of relevant areas, traditional ground surveys with drilling, sampling and probing, as well as geophysical surveys that provide ground data without any excavation or drilling at all. Geophysical surveys involve electrical methods, electromagnetism and seismic waves. This can detect vital geotechnical properties such as bedrock depth, soil stability and rock quality, as well as map reservoirs of water or oil, metal objects or sources of contamination.

If present-day geophysical technologies are integrated with traditional geophysical ground surveys, it is possible to produce very detailed, continuous and comprehensive models for application within numerous areas.

NGI
Pictures from AEM survey (left) to map the ground. Results from AEM survey along Intercity routes in the counties of Vestfold and Østfold (right)