Bothnia line, AGF in Clayey Soils; a Review of the Thawing Temporary Stabilisation and Hydraulic Sealing through F

Important results from the project

The objectives were largely met Soil samples could be taken from different depths and analyzed. Field investigations of the ground could be carried out. Geodetic measurements could be carried out, and it was determined that the settlements amounted to 1.8 m. One objective could not be carried out: registration of total pressure on the tunnel roof from the tunnel level, partly because the instrument broke, and partly because it was difficult to get permission to go down into the train tunnel.

Expected long term effects

The purpose of the development project has been, i.e., to follow up on the forecasts that were developed in a laboratory environment, to see if these can form the basis for correct settlement forecasts. The answer to this question is that the forecasts in the lab do not correspond to actual settlement. In addition, the purpose is to investigate whether the thawed soil has retained its changed properties that it obtained in the freeze-thaw tests in the laboratory environment. The answer is yes.

Approach and implementation

Review of previous projects and results. Meetings with reference group. Planning of * field measurements * lab experiments Participation in seminars organized by TrV FoI-portfölj, BIG. The activities were right. The schedule was lagging, unexpected problems arose in the field. The area had to be cleared. Too much snow, too little ice, great water depth, built piers that were torn apart the next winter. Then had to rent a rubber boat and dry suit to be able to measure.