Paramix mid-term meeting in Barcelona November 13, 2002 Status of Swedish test sections for cold in-situ stabilization
Test sections are located northwest of Umeå Stockholm The location of the test sections is approximately 650 kms north of Stockholm Gothenburg
Test road before stabilization The length of the test road is 1600 meters. The structural strength was measured before any measures using a FWD. Test road before stabilization
FWD measurement Example only This is an example from another section of a Swedish road. On the test sections sensors were located 0, 200, 300, 450, 600, 900 and 1200 mms from the center of the load plate.
Cores were taken in each lane and direction every 50 meters.
Average thickness 50 mm Thickness measured, composition analyzed (bitumen content and grading) and bitumen recovered and analyzed.
Unbound base .... Under the surfacing .... Samples og the unbound layer underneath the asphalt were taken and analyzed. Under the surfacing ....
Swedish test sections emulsion emulsion no emulsion Test 1 *added SA 16 SA 16 SA 16 100 mm new base emulsion emulsion no emulsion 50 mm AC 100 mm gravel base SA means soft asphalt wearing course (thickness 45 mm). On the first test section 50 mm new aggregate (4-32 mm) was added and mixed with the existing asphalt and 50 mm of existing gravel base. On the second section 50 mm new aggregate (0 – 32 mm) was added... In the second step emulsion was added up to about 4 % (residual binder content!) of the layer. The reference section has no emulsion added, only mixing was performed. A new base layer was added on top. This is the common Swedish way to reinforce a road of this type. 50 mm aggregate A* 50 mm AC 50 mm gravel base 50 mm aggregate B* 50 mm AC 50 mm gravel base Test 1 *added Test 2 Reference
In-situ cold stabilization steps Adding unbound material New wearing course Emulsion mixed in ”Dry” mixing Existing Steps from left to right... Dry mixing means only water added. After dry mixing the road is shaped by means of a grader and compacted.
Emulsion production unit The bitumen emulsion was produced in our own emulsion plant also located in Umeå, close to the laboratory.. Emulsion production unit
Bitumen grade used for the bitumen emulsion The bitumen grade chosen was 330/430. It is a relevant choice taking into account the climatic conditions, workability and compactability during execution of the work. Bitumen grade used for the bitumen emulsion
First milling after adding new aggregate
Shaping after mixing in emulsion...
Surface finish after compaction with two rollers (oneheavy pneumatic and one smooth vibratory)
Samples were taken one every 50 meter on each side of the road
Laboratory compaction was performed using a gyratory compactor with 150 mm perforated moulds (allows water to escape)
A total of 69 specimens were prepared using the same procedure A total of 69 specimens were prepared using the same procedure... Now waiting for curing sawing and any analysis necessary for those building models