Wind turbine shallow foundation reinforcement

[Sjotroll]

Hello!
Me and my colleague are designing a circular shallow foundation for 100 m high wind turbines. We've already done all the stability checks, and are now in the process of designing the required reinforcement. We already did some calculations and found the required reinforcement in the bottom and top zones which will be places radially and circularly around the foundation, and stirrups for shear force. But seeing other projects and examples of wind turbine foundations there should be much more reinforcement than we calculated. We understand that much of it is there for "constructive" reasons and can't really be calculated, but we were hoping to find some guidelines and rules for reinforcing such a foundations completely (i.e. choosing all the required reinforcement, and not just the statically required reinforcement). There may also be other specific statically required reinforcement, such as the cages under the shaft for which we also didn't find any guidelines.
Does anyone here have experience in designing such structures, and do you know of any literature/standards/handbooks etc. which cover in depth the reinforcement of wind turbine foundations?

I also posted this question in the foundation design forum, but maybe many of you structural engineers who know more about reinforcement do not check that forum in the geotechnical engineering section, so I'm also posting this here. Hope there isn't a problem with posting the same thing on different forums.

Thanks in advance.

 

[oldestguy]

Erase one of the posts. Only one allowed here. No more than one needed for us. Why don't you post a cross section of your pressure diagram. Do you go so far as to have a triangular pressure distribution? Edit: Also do a search, preferably via ASCE. This one came up for me: "Foundation Soil Response to Wind Turbine Generator Loading"

 

[r13]

How you modelled the foundation system, and how you derived internal shear and moment? Please describe the method used in the analysis. Drawing will help.

 

[NepEIT]

IF you are designing Foundation for Wind Turbine refer to DNV/RISO standards.
When I design the turbine foundation I generally model the structure in FEA software like SAP2000.
Get the internal stress and design accordingly.
For Wind Turbine foundations Fatigue is another important criteria. Those extra reinforcement you are talking about might be for fatigue.