Steel piles are usually rotted H shapes or pipe piles. Wide-flange beams or I beams may also be used; However, the H-shape is especially proportioned to withstand the hard driving stress which the pile may be subjected.
Splices in steel plate are made in the same manner as in steel columns, i.e., by welding (most commonly) or by bolting. Except for small projects involving only a few piles, currently most splices are made with prefabricated (and patented) splices connectors. For H piles, web plates are prefabricated in the form of two channels back-to-back, of adequate length which fit snugly against the web and inside flange.
The splice is then welded to the web across the ends and the flanges are butt welded to complete the splice pipe pile splicers consists in a ledge ring with an inner dia slightly larger than the pipe outer dia. The two sections of pipe to joined rest against the inside ledge and an end weld is made around the pipe at both ends of the splice. Generally these splices will develop the strength of the pile in compression, tension, bending, and shear to satisfy most building code requirements.
When a pile must be spliced to develop adequate embedment length, all the necessary equipment should be standing by so that when the hammer is shut off the splice can be quickly made. If this is not done – and sometimes if it is done-the soil tends to set or "freeze" about the pile, and resumption of driving is difficult and sometimes requires changing hammers. These large driving stresses may cause considerable damage to the upper part of the pile. This is a phenomenon which is independent of pile materials.
No comments:
Post a Comment