GICPs is one of the ASC's suggested options for reinforcement of sandy soil with loose relative density to moderate and clays and silty with relative consistency of soft to medium in order to increase the bearing capacity and stiffness modulus, reduce settlement and retrofitting at the liquefaction. A Gravel Impact Compaction Pier consider as a reinforcing soil and not a foundation element or a deep foundation. Technology and construction of Gravel Impact Compaction Piers system which is known as GICPs in format of 3 indoor inventions over the years of 2014_2016 by research and development unit of this high-tech company registered in patent offices of Iran. These inventions won first place in several festivals and country patents. Here of, implementation of the two national projects located in Bushehr port from Iran in order to retrofitting soil against liquefaction and conducted extensive researches in this field, lead detoxify defects. The construction method of GICPs rely on implementation of 4 main steps; (step 1) excavation and pass the dense layer or rock fill, if needed, (step 2) once or twice hammering the special shuttle into the loose soil, casing installation and pouring gravel materials into the pipe and then removing it, (step 3) hammering the ended pile with conical shape into gravel pier frequently and feeding gravel to the end of pier, (step 4) hammering the top of piers and between them with short tamper and Implementation of wide gravel berm on the ground.

Benefits:

Some of the features and technical and economic advantages of GICPs are as follows:

- No drilling at the location of the piers in the weak soil layer using by water jet, compressed air or mechanical auger and no need to remove and transportation of the soils inside the well to out of the workplace.

_Possibility to construction in the submerged conditions like coastal land below the sea tidal level.

_The possibility of implementing GICPs in loose granular and liquefiable soil layers under hard soil and rockfill layers.

_Increasing the density of the soil around the piers in several stages until reaching the desired density and not relying on the piers drainage property for against liquefaction during an earthquake.

_Implementing GICPs only with using conventional mechanical shovels.

_No contamination in workshops and the environment.

_High speed and low cost in implementing piers.

_The possibility of implementing piers as groups and step by step.

_Floating performance of GICPs and bear the load without relying on strong layer at the end of pier.

_Fast retrofitting loose sand against liquefaction in manufacturing GICPs.

_Ease of implementation method, the possibility of making equipment in each area and no need for heavy and large equipment.

Applications:

_Increase the bearing capacity and reduce settlement on soft and compressible soil beds under the foundation of residential, office, commercial, industrial, military, sports and etc. buildings.

_Increase the bearing capacity and reduce settlement on soft and compressible soil beds under the foundation of tanks, chemical and petroleum products.

_Settlement control of embankment road and access ramp of bridges.

_Natural slope stabilization.

_Prevent settlement and failure of culvert under the roads.

_Increase the bearing capacity and reduce settlement on soft and compressible soil beds under the railway track.

_Reduction of the liquefaction potential in the active seismic areas.

_Reinforcing the soft and compressible soil beds under the concrete slabs in industrial and coastal projects.

_Settlement reduction and failure control of soft soil beds under the retaining walls. 

_ Reinforcing the soil beds under the strip and mat foundations and storage containers.