Construction over soft foundation soil is something that cannot be avoided in modern times due to lack of available space for construction. There are three limiting factors related to the construction over weak foundation soils:

The rate of construction has to be closely controlled. Soft soils are compressible resulting in large consolidation settlements. It may restrict the geometry to which the embankment may be built. The embankment fill may slide on the underlying soft soil

These problems can be mitigated by the construction of a basal platform to spread, span or dissipate the construction loads, downwards into the ground. The basic functions performed by a basal platform like geogrids, geotextiles include:

Accommodates higher loads Reduces differential settlements & maintenance cost Reduces platform thickness and thus saving on vehicle movements and quarrying Strengthens the platform construction Reduces project duration and hence cost.

1. Basal Reinforcement for Soft Ground:  The presence of soft or wet ground beneath an embankment can cause settlement problems. A platform of granular material, reinforced with geosynthetics, can limit differential settlement by providing a more competent foundation for the embankment besides increasing the rate of constructions substantially. Geogrid and geotextile reinforcement can allow construction in areas previously considered out-of-bounds for building infrastructure upon due to soft ground.
   
   
2. Piled Embankments: Piling is one of the most common techniques for transferring loads from the embankment to the firm stratum to mitigate the problems related to soft foundation soils. Consequently the soft foundation soil has no direct impact on the performance of the embankment. A recent development of the piled embankment technique is to provide geosynthetic reinforcement spanning in catenary between the pile caps. This permits the spacing of piles to be increased and size of pile caps to be reduced. In addition, the geosynthetic reinforcement counteracts the horizontal thrust of the embankment fill, as a result of which the raking piles can be eliminated.
   
3. Over Voids:  Sudden settlement of the ground due to naturally occurring voids, old mine workings, Underground River in or ground pumping are difficult to predict and expensive to repair once they have occurred. The use of geosynthetic reinforcement beneath infrastructure in these areas can prevent catastrophic collapse.