Is a Dam Abutment also a Foundation

[BigH]

Mates,

I am pulling out my hair (yes, I still have it) on a number of questions that keep arising on my latest project. This question conderns the definition of "dam foundation". There is a special requirement that the dam foundation be covered by one layer of 0-300 mm alluviul material whereas the bulk of the material to be placed will be 0-700 mm.

I consider the abutments of the Dam to be foundation as the dam rests on the abutment.

In other words, the foundation is not just the river bottom.

There are those here who believe that the abutment is not a "foundation".

Thougths?

 

[SlideRuleEra]

To me, if a foundation supports anything that is essential for resisting hydrostatic pressure from the impoundment... it is "dam foundation".

http://www.SlideRuleEra.net

 

[GeoPaveTraffic]

On the dam's that I've worked on, the abutments are considered foundations. In fact, I think you are more likely to have problems on the abutments than you are on the relatively flat bottom.

Mike Lambert

 

[jdonville]

Agree, the abutments can be relatively problematic.

 

[BigH]

All, abutments, for sure, can be problematic - both real and, in many cases simply perceived. The issue here is many, due to "wording" meaning (especially in translation) see abutment to be different from foundation. Semantics.

 

[jdonville]

The definition of "foundation" is 'where the structure is supported by the earth'.

 

[BigH]

True,but sometimes it is hard to convince someone who is rigid to the core; and they are taught, seemingly, that abutments are different from foundations. USSR training?

 

[jdonville]

You may want to ask, in a Socratic way, "OK, if the abutments are not foundations, then they must be self-supporting, right?"

 

[geotechguy1]

It sounds like you need to clarify with the designer what they actually meant.

In the context of dams I have always understood 'foundation' to mean 'the dirt or rock that the dam is sitting in'

Unfortunately this is one of a lengthy list of geotechnical terms where different people use them to mean different things in the context of different geotechnical structures and in different countries

 

[BigH]

Geotechguy - you are correct - it is not the designer but the interpretation, in construction, of the specifications. My view is that the abutments are "foundation" as the dam is sitting on them; the Tajikistan engineers didn't see it that way by definition. Foundation is not the same "word" as abutment. Oh well, I won!