The moment in the cross-section for the applied curvature distribution was
determined by summing moments about the neutral axis.
The moment due to the self weight of the pile was determined by assuming a
trapezoidal distribution (see Fig. 6-43) of the weight due to the fact that the pile was
tapered and the wall thickness variable through the length. Based on the uniform
distribution of weight assumed the total weight of the pile (W) was equal to:
W= L.w +0.5.L.(w2 W1) (6-1)
The magnitude of the uniform weight w2 was related to the magnitude of weight wl
in terms of the cross-sectional areas of the tip and butt sections. The magnitude of w2 was
equal to the following:
Ab
2 =-.W1 (6-2)
A
where Ab was the area of the butt and A, was the area of the tip of the pile.
35,
L = 38'
Figure 6-43. Self weight distribution of spun cast piles
The expression in Eq. 6-2 was substituted into Eq. 6-1 and the magnitude of wl was
calculated. Then w2 was calculated by substituting the magnitude of wi into Eq. 6-2.
Once both wi and w2 were known the moment due to self weight at the south load point
was calculated using static analysis. The self weight moment was calculated at the south
load point because the specimens failed at that point.