Enhancement of Raft Foundation Using Micro Pile Technique
Raft foundations are one of the shallow foundation techniques used for carrying high loads of the building especially on compressible soil formations with high differential and total settlements. In this paper, a case study of a high rise building having non-eccentric loads is established using raft foundation. There was compressible soil stratum starting from 8.0 m down to 12.5 m underneath the raft foundation. Due to the non-eccentric loads of the building and the compressible soil layer which caused the increase in the tilting of the building with time. According to the continuous of the building movement, enhancement method should be used to overcome this moving. Micro pile technique was designed and established at the tilting sides of the building. A new raft foundation was added at the top of the old foundation to insure connect of the executed micro piles with the old raft foundation. Measurements of the tilting or the movement of the building were continued before and during execution of the micro pile technique. Observations showed a good enhancement in the behavior of the foundation system after using the new system of micro piles as there was no more tilting in the building or the differential settlements.
The authors would like to thank Prof. Dr. Adel Hammam (Geo-institute) and Eng. Hayel M. El-Naggar for their collaboration and assistance during performing of the present study. Special appreciated to the contractor company staff executing the micro piles for their help and patient.
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