A common mistake in San Bernardino is assuming the ground is uniform across the city. The alluvial fans from the San Bernardino Mountains and the older clay basins near the Santa Ana River behave completely differently. Many contractors skip a proper settlement analysis and end up with cracked slabs or misaligned footings within months. We perform settlement analysis in San Bernardino using consolidation tests and oedometer data to predict both immediate and long-term deformation. Before placing any foundation load, we recommend a consolidation test to measure preconsolidation pressure and compression index.
In San Bernardino, ignoring the preconsolidation stress of old clay basins can lead to differential settlements exceeding 25 mm within two years.