What damages do “expansive soils” cause when not properly accommodated or remedied before building?
Microscopically, these clays are made up of plate-like particles that absorb moisture and can expand to more than 100 percent of the original size. This “swell pressure” between particles can push up and crack concrete slabs, driveways and walls that have less weight than the soil pressure. When these soils dry out, the reverse process occurs and shrinkage results. Damage to the improvements can be done as readily by the lifting as the collapsing.
