Pile Lateral Capacity using COM624 or LPile 1

[ohyeh]

Structural engineers asked us to provide lateral loads on pile foundation allowing 0.5" head deflection for the following condition:
1. Pinned;
2. Fixed at the underside of a foundation;
3. Pinned 1 ft above grade;
4. Fixed 1 ft above grade.

I believe 1 is free head condition with applied lateral and vertical load but without moment; 2 is fixed head condition with restrained rotation. But what is the difference btw 3&4? Please advise how to handle them in the softwares.

Thank you!

 

[Panars]

For conditions 1 and 2, I would put the pile top at the ground surface with the appropriate end condition as you stated. For conditions 3 and 4, I would use the same end conditions as 1 and 2, but I would put the top of the pile 1 foot above the surface of the soil.

In LPile, put 12 inches as the distance between the top of the pile and the top of ground for conditions 3 and 4.

 

[miecz]

Boundary Condition Types 1 and 3 can have an applied moment in addition to applied lateral and vertical loads.

 

[Panars]

miecz-

At the location of the pinned connection, there is no moment on the pile. For condition 3, there is no moment at the pinned connection, but there would be a moment in the pile at the ground surface. However, you don't need to input this moment into Lpile or COM624P, as it will calculate the moment for you given the loading at the top of the pile.

 

[miecz]

Panars-

For Boundary Condition Type 1, ohyeh's conditions 1 and 3, the user can input a moment at the top of the pile. For the type of work that I do, there is often a pole with a moment connection.

 

[Panars]

I agree that you could input a moment. But for a pinned connection, there wouldn't be a moment.