Melbourne's climate swings between drought and intense storms, which directly impacts subgrade moisture and the long-term performance of reinforced soil structures. We have seen geogrids specified without accounting for these cycles, leading to differential settlement within two years. A proper geogrid specification must consider the design life, ultimate tensile strength, and creep reduction factors under sustained load. To start, we always verify the subgrade bearing capacity with a plate load test before selecting the grid type. This step avoids mismatches between the geogrid stiffness and the actual ground conditions we find across Melbourne's clay and silt profiles.
A geogrid specified without creep reduction factors for Melbourne's clay subgrades can lose half its design strength within a decade.