Laboratory Testing on Geosynthetics of Reinforced Foundation Ground

conference paper

English

The paper describes results of experimental observation of axial strain mobilization process in geogrids used as reinforcement of soil base layers or foundation subsoil layers situated generally on a main body of weak and soft soil which are vertically loaded by a static pressure concentrated on a part of their top surface. The experiments were carried out in the form of conventional static foundation load tests on two Test Models different in geometrical arrangement, type of foundation, soils and loading scheme. In both Test Models an instrumented geogrid was installed between an upper thin layer of a strong and stiff soil and a lower thick layer of a week and compressible soil. The geogrid instrumentation was based on strain gauges installed on five locations of the geogrid central rib and in the 2nd Test Model on pressure transducers placed in the soil mass below the reinforcement in the same plan locations as the strain gauges. Before constructing the Test Models a suitable method of strain gauges installation on polypropylene geogrid had to be successfully resolved. The loading phase was carried out either according to the appropriate Czech Technical Standard or by statically increasing the foundation bearing pressure until onset of soil failure. Foundation settlement, reinforcement axial strain and soil normal vertical stress (Second Test Model only) were recorded as a function of the applied soil-foundation stress. The main observation result was that only small axial strains and hence normal forces mobilized at ultimate vertical loads.

Geosynthetics, subsoil, laboratory testing,

MIČA, L.; UHRIN, M.; VESELÝ, J.

1. 3. 2004

DGGT a TUM-ZG

Mnichov

3-00-013305-4

Geotechnical Engineering with Geosynthetics

745

748

4