University of Natural Resources and Life Sciences, Vienna (BOKU) - Research portal
Gewählte Master / Diploma Thesis:
Paul Hellmeier
(2010):
Bodenverbesserung - Untersuchungen an expandierendem Polyurethan Hartschaum.
Master / Diploma Thesis - Institut für Geotechnik (IGT),
BOKU-Universität für Bodenkultur,
pp 136.
UB BOKU
obvsg
- Abstract:
- This thesis deals with various options for soil stabilization. The aim is to increase the bearing capacity of shallow foundations. In particular, a grouting technique is investigated with a two-component polyurethane grout (GeoPlus). The grout is injected into the soil and polymerized under volume expansion. The strong expansion effect of GeoPlus causes compression of the surrounding soil in the vicinity of injection. Some large scale tests in three representative soils (cohesive and cohesionless soil) are carried out and documented technically. The improvement of the mechanical behavior of soil through grouting is investigated by an extensive testing program, which includes the penetration resistance by dynamic probing, the measurement of density and water content with a nuclear gauge, the static and dynamic plate loading tests. The large scale tests are carried out under clearly defined and reproducible conditions (soil density, water content, etc.). The tests show that the mechanical behaviour of the investigated soils is significantly improved by the expanding grout GeoPlus. In cohesive soils (clay and loess) the grout is mainly formed in thin horizontal layers. In gravel, the grouting led to a conglomerate soil structure with remarkable increase in the ultimate bearing capacity. Finally, the applicability of this method is shown by the repairing work on a building, which was damaged by settlement. The width of cracks was halved by grouting. In addition, the building was raised by about 7 mm with no visible damage to the walls.
- Beurteilende(r): Wu Wei