hinge. The spring stiffness was determined by dividing the section moment by the

calculated rotation at each load increment.









 27'









 3 @6'


Figure 7-4. Visual analysis model pile bent system (load case 2)

 Once the rotations at specific loads were determined, a static lateral load was

applied to the pile bent system that produced the target moment at the plastic hinge

locations. The rotational stiffness of the plastic hinge locations was then modified to

much the rotations for the specific load. The required stiffness of the rotational springs

was calculated by dividing the moment by the target rotation at each load increment. The

lateral displacement for each static load increment was recorded and the load-

displacement curves of the pile bent system plotted for each type of pile.

Results for Load Case 1

 Both the cast in place glass square (CPGS) and round (CPGR) piles were used. One

pile bent for each of the two shapes was analyzed as well as three pile bents using

prestressed concrete piles. In the first of the prestressed pile bents, piles from the St.