How toanalysis pile raft foundation?

Answer 1

its a vast subject in pile foundation. If you have studied civil engineering you will get a clear picture of it. Ask any civil engg who is very close by to you. Its a very interesting subject.

Answer 2

The best foundation type depends on the particular soil conditions under your house. A raft foundation is well suited for potentially unstable soils, or soils that are highly compressible. The raft system reduces the pressure on underlying soils. To some extent, a pile foundation is used in similar conditions as a raft foundation. Piles need to be installed deep enough to extend to a resistant strata of material, such as gravel or bedrock. In some locations the depth of silt, sand or fine soil is too deep to make a pile foundation a practical consideration. A raft system may be the only practical solution. Another method commonly used in potentially unstable soils, is to put in a spread footing, which requires excavating to a particular depth below the site grade, and significantly wider than the footprint of the house, and backfill with compacted, structural gravel fill. Once in place, a conventional concrete foundation can be erected on the structural fill. A structural engineer should have collected and analyzed core drill samples, and/or conducted a load test on the soil. The engineer would then design a foundation based on the specific soil conditions and the structure. Ask the developer for the engineering report and structural design for the foundation system to confirm how the decision was made to use this foundation type. If the developer cannot produce this report and structural design, you may have a problem and grounds for possible litigation against the developer, depending on building permit requirements in your country.