Offshore Pile lateral load 1

[SomeQuestion]

Hello, I want to ask about the Reese and Matlock method of lateral load, it uses some coefficients (Ay,As,Am,Av,Ap. and By, Bs, Bm , Bv,Bp) in a formula containing the shear and moment applied to find either slope, deflection, soil reaction ,moment at a certain depth. So I am trying to use it for an offshore pile, to find the maximum deflection at top of the pile, or moment at top, basicaly under the platform directly.. So for this level for which z is negative, (above sealevel), the coefficients A and B cannot be found in the table, because we are looking for deflection above the ground, and all depth in table are positive. Is there a certain way to solve this issue. Also any help about finding the actual ultimate lateral capacity or moment of the pile to compare it with respective loading found by this method, is welcome.

 

[CarlB]

The Reese-Matlock method models pile behavior over just the embedded portion. The horizontal load on the "stickup" is converted to a lateral load & moment applied at the ground level. To determine stresses in the above-ground portion, you would model that separately. For instance you could model it as a free-standing column, fixed at a distance below ground, at the "point of fixity". That point is usually 5 to 10 pile diameters, or the point of zero deflection. A more accurate model may be to analyze the portion above the groundline, fixed at the groundline but with an initial deflection & slope as determined from Reese-Matlock.