Hydrocompression Settlement of Deep Fills

Abstract

TWO subdivisions in southern California constructed on compacted‐sandy‐clay fills up to 100 ft thick experienced settlement damage several years after construction. These fills were designed and constructed using the same procedures that had been used successfully in the area for many earlier developments. Field investigation showed that the water content in the fill had increased considerably after construction. This increase in water content could have been caused by rainfall, by irrigation of lawns and plants, and by infiltration of ground water into the fill from the underlying natural formations. Laboratory tests on compacted samples were used to measure compression due to wetting, and a simple analytical technique was used to calculate the magnitudes of the settlements that would result from wetting. The calculated settlements effectively bounded the measured field settlements.