IEEE 691-2001

The material presented in this design guide pertains to the design of foundations for conventional transmission line structures, which include lattice towers, single or multiple shaft poles, H-frame structures, and anchors for guyed structures. It discusses the mode of loads that those structures impose on their foundations and applicable foundation performance criteria. The design guide addresses subsurface investigations and the design of foundations, such as spread foundations (footings), drilled shafts, direct embedded poles, driven piles, and anchors. The full-scale load testing of the above-listed foundation types is also presented. This design guide does not include the structural design of the foundations nor the design of the structure. Citations [B5] and [B50] provide guidance for the design of lattice towers and tubular steel poles, respectively. The foundation engineer should have an understanding of the magnitudes and time-history of various loading conditions imposed on the foundations in order to provide a suitable foundation to support the transmission line structures under the actual loading conditions that may be reasonably expected in actual service.