Caisson Foundation design using soils report

[bujaman]

I am fairly new to foundation design and have a question about where to start. I received a soils report from the client and need some help interpreting it. The number of STP blows goes from 16 at 9m depth to 27 at 10.5m, and then to 50 at 12m. If I am reading this correctly, this is where my foundation needs to be in order for there to be stability. Like I said, I am new at this, so any help interpreting this would be appreciated. I have attached the soils report as reference. Thanks in advance.

 

[PEinc]

Usually, the geotech is given column loads by the structural engineer. The geotech then recommends one or more types of foundations and where they should be founded. These recommendations consider allowable bearing capacity, total settlement, and differential settlement between foundations. You should be asking your geotech for the explanation and his recommendations. That's why they are hired.

You seemed to have hired a testing lab/driller who gave you a boring only - no geotech report, no engineering, no recommendations, no analyses, etc. Additionally, there is no P.E. seal on the boring report. A seal or stamp with just a company's name is worthless. You need a geotechnical engineer.

http://www.PeirceEngineering.com

 

[oldestguy]

I understand the policy of this WEB site is that we do not design anything. Therefore, do not expect that recommendations will be given for where to set the foundation or with what bearing pressure. PEinc has it right.

 

[GeoPaveTraffic]

As PEinc pointed out, what you have is a boring log; nothing else. Either you need to have enough knowledge and experience to design the foundation based on the log or you need to hire an engineer who does.

As a starting point, the type and depth of the foundation will depend on the type of structure being cosntructed, the loads of that structure, and the amount of settlement and/or deflection that the structure can withstand.

Good luck.

Mike Lambert

 

[hokie66]

Your project seems to be in Malaysia, and maybe a telecommunications tower. Other than the boring log, that is all we know. You need further discussion with your client as to the requirements for the tower. Some of these things require rigid controls over deflections, vibrations, etc., while others are not so critical. Your client may have other similar installations which can be used as a starter. Best to learn from local experience, rather than from people on the internet.