Dear reader throughout last few posts we were discussing about collapsible soil. Collapsible soil is a problematic soil and foundation settlement is common and sudden in this type of soil. In south western portion of United States, we have faced many problems with this type of soil.
There have several methods to fight with collapsible soil. Of these, we are discussing here about flooding techniques. In this technique building footprint is flooded, alternatively wells can be provided to force water to penetrate through stratum of collapsible soil.
In some collapsible soil there have some amount of clay content or chemical binder that provide its strength initially when the soil get wet the binding property is diminished and soil get collapsed. In case of cohesionless collapsible soil, also water is the key agent that produce collapse in foundation soil.
In flooding techniques when wetting front passes through ground, this soil get densified until it reach equilibrium state. There have some precautions in using this technique like
-If there have adjacent structures that also supported on collapsible soil the flooding or water forcing techniques are not allowed as this may lead to damage to these structures.
-Before ensuring to be the site safe against collapse, subsurface exploration and extensive laboratory testing have to be performed to find out efficiency of this process.