Soldier Pile Wall (Braced Sheeting)
When analyzing braced sheeting (pile curtain, steel I-section or user input of A, I, E, G) the following approach is adopted to determine the earth pressures:
Up to the depth of the ditch, the pressures are determined with respect to 1 rm of the structure width. Below the ditch bottom, the earth pressures are multiplied by the coefficient of reduction k (the "Coefficient of pressure reduction below ditch bottom"). This coefficient can be input (in the frame "Geometry" as a parameter of the section of a structure) or automatically calculated.
If "Landfill of soil" above the ditch (frame "Excavation") is input, then the pressures within this section are computed with respect to the entire width of the wall (k = 1).
The coefficient of pressure reduction below ditch bottom k can be approximately determined (for very conservative design) according to:
where: | a | - | longitudinal spacing of soldier beams, or spacing between piles |
d | - | width of soldier beam, or diameter of the pile |
The real value of the coefficient k also depends on the soil type and space effect of earth pressure. Real values of this coefficient (based on experiments) are two to three times higher than values calculated with the help of the previous formula.
Braced sheeting - schematic view of retaining structure