L-pile deflection to depth chart 1

[stillfan1]

I have a reinforced drilled concrete pile that is free at the head and embedded into sandstone for 16 ft. When I view the Pile deflection to depth chart it is giving me a negative deflection of 2.4 in how is that possible with rock. I have attached the image. I would have suspected it to respond more in a fixes manner at the rock level. See attached image. Any thoughts?

 

[azcats]

Looks very rigid. I'd expect some curvature differences along the length of the shaft.

What diameter pier?

But you're right that does look 'off' - you'd expect the point of rotation to be in the rock layer. I guess we'd need to evaluate the input data and or geotech info to offer much real advice.

What do the shear and moment graphs look like?

 

[PEinc]

Too conservative with the rock strength properties?

http://www.PeirceEngineering.com

 

[WARose]

Looks like some sort of error to me. And that is on multiple levels: you'd think the lines would have more curve to them. (Assuming we are talking about soil surrounding the pile....which is why someone would use L-Pile in the first place)

And if the rock is displacing that much.....you need a deeper socket.

Modeling sockets can get tricky in L-Pile.....sometimes you get a "shear spike".

 

[r13]

Agree with WARose's comments. Ask more experienced person for modeling mistakes, the property does not seem right.

 

[Settingsun]

Have you used the strong rock model? It has a brittle failure point which causes progressive failure of the rock down the pile and is not realistic.

Post the plot of ground reaction vs depth, and the rock p-y curve.