Test sites
To cover the main typical soil conditions, five test sites were chosen.
Test sites with the following dominant soil were sought:
- normally consolidated medium plastic clay => Onsøy near Fredrikstad (1)
- normally consolidated low plastic silty clay, where time effects are expected to be most significant => Stjørdal, Mid Norway (2)
- stiff overconsolidated medium plastic clay => Cowden, UK
- loose sand => Larvik (3)
- medium dense sand => Mjøndalen (4)
Test piles
At each selected test site, six 50 (or 40) cm diameter steel piles, 15-25 m length are installed. All piles will be loaded in tension to simplify loading arrangements. The proposed load testing program for all sites will be as follows:
- Pile 1: Load testing after 1 month, 3 months and 6 months, 1 year, and 2 years
- Pile 2: Load testing after 3 months, 6 months, 1 year, and 2 years
- Pile 3: Load testing after 6 months, 1 year, and 2 years
- Pile 4: Load testing after 1 year and 2 years
- Pile 5: Load testing after 2 years
- Pile 6: After three months a constant load of approximately 60 % of the first failure load from Pile 1 will be applied to Pile 6. The pile will be tested after having experienced this load for 1 - 2 years.
The test sites in Norway
Site investigation program
The standard site investigation program carried out at each test site consists of:
- Rotary Pressure Soundings or Total Soundings
- 54 mm sampling to verify general ground conditions (if necessary)
- minimum 3 CPTU's to 25 meters
- 72/76 mm piston sampling to 25 m depth in one borehole
On soil samples retrieved by piston sampling, standard laboratory tests were performed as follows:
- routine tests all samples (water content, unit weight, organic content, Wp Wl, fall cone, UC, UU)
- mineralogy selected samples
- grain size selected samples
- 3 oedometer tests
- 3 Triaxial tests (CAUC, CAUE, CID)
- 3 DSS tests
