Laterally loaded pile analysis
Laterally loaded pile analysis
(OP)
I am analysing the lateral capacity of steel pipe mono pile. The pile is in a marine environment and loaded at (Elev. +9 MLW), the ground elev. is at (Elev. -19 MLW), the pile tip is at (Elev. -120 MLW). The pile O.D. is 5 feet. I have couple of software: FB multi pier and Lpile which I see both are capable to analyze a single pile. I have couple of questions:
- Which software is more aproperiate for the analysis?
- Both programs require input for subgrade modulus (lb/in^3)for the clay soil (soft, stiff, or V.stiff). Is there any approximate values for the subgrade modulus for each of the above soil types?
Thanks
- Which software is more aproperiate for the analysis?
- Both programs require input for subgrade modulus (lb/in^3)for the clay soil (soft, stiff, or V.stiff). Is there any approximate values for the subgrade modulus for each of the above soil types?
Thanks





RE: Laterally loaded pile analysis
0.5 kgf/cm3 soft soils
4.0 kgf/cm3 firm soils
12.0 kgf/cm3 very stiff soils
Source is Albert Fuents, RC Buildings book, which does not indicate (but must be) being ks30 values (1 ft square plate)
I have also found that to mimick the actual (probabilistic) behaviour for ordinary buildings in non extremely problematic soils, and with mats, the ks30 without any scaling for foundation size may give a better approximation than applying the scaling. Have no clear idea on how this will relate or how to be considered unto your pile intent.
RE: Laterally loaded pile analysis
Why bother analysing this pile with a high level computer package when you are going to approximate (guess) the subgrade modulus? Or maybe you are waiting for the geotechnical report and just want to get something happening
Arguing with an engineer is like wrestling with a pig in mud. After a while you realize that them like it
RE: Laterally loaded pile analysis
Computer analysis assuming elastic-linear deformations of soil does give the engineer an 'answer' of the lateral displacement at the pile-head. I have never seen anyone in my office check the displacement at the pile-head except for myself, mainly because of the lack of useful soil-structure information that is provided by geotechnical engineers in my part of the world. I have found the geotechnical engineers in Australia to be lacking technical knowledge. I had a geotechnical engineer say to me the other day that a particular rock had a 350kPa (50psi) allowable bearing capacity or a 2250kPa (325psi) ultimate bearing capacity. That is a factor of safety of 6.5...
RE: Laterally loaded pile analysis
asixth- but is your observation applies if the pile is 5' diameter
Thanks everybody
RE: Laterally loaded pile analysis
RE: Laterally loaded pile analysis
My post wasn't the most helpful in answering your question. I don't think results would vary because of the size of the pile because the soil reaction is taken over a rectangular area so the results should be linear. I.e. larger piles, more soil resistance.
I am going to work now so I will post so information on soil subgrade modulus that my local DOT sent to me.
RE: Laterally loaded pile analysis
RE: Laterally loaded pile analysis
8100 KN/m3 for Soft Clay
27000 for medium stiff clay
136000 for stiff clay
271000 for very stiff clay
540000 for hard clay
the above values are reduced for cyclic loading applications:
----- KN/m3 for soft and medium stiff clay
54000 for stiff clay
108000 for very stiff clay
215000 for hard clay
Hope that helps.
RE: Laterally loaded pile analysis
RE: Laterally loaded pile analysis
RE: Laterally loaded pile analysis
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