Improvement to bearing capacity
In the construction of heavily trafficked areas such as parking lots, a stable subgrade with sufficient bearing capacity is required. When installed between the subsoil and the base course, Secugrid® Q geogrids, made from high strength, extruded monolithic flat bars, with welded junctions, are particularly well suited for this application.
The coarse grained cover soil interlocks with the Secugrid® Q geogrid (grid apertures ≥ 28 mm) creating a bond. This immediate interlock provides a horizontal force transfer which increases the bearing capacity of the soil due to the high force absorption of Secugrid® – even under low elongation. The required bearing capacity can be achieved without additional expensive soil exchange, and in some cases, the base course thickness can be reduced.
Secutex® separation and filter nonwoven geotextiles are used to prevent the migration of fine particles into the base course. The design approaches for the nonwoven are described in further detail under the chapters “Filtration with geotextiles” and “Separation with geotextiles”. To facilitate the installation and create shear strength transfer, Secugrid® and Secutex® components are pre-manufactured into a bonded composite product – Combigrid®. On extremely soft subgrade, the bearing capacity can be markedly improved by using multiple layers of Secugrid® geogrids.