Simplified Lateral Load Design Equations and Applications for Embedded Wood Pole Structures

Abstract

Embedded wood pole foundations have been successfully used over many years for single-pole applications such as flag poles and utility poles. This type of construction has also been used for buildings for hundreds of years but predominantly for agricultural use. More recently, due to improved technology, construction utilizing embedded wood pole foundations for a wider range of buildings is becoming increasingly more popular due to its cost-effectiveness and simple approach. Wood poles embedded in concrete can be a potentially efficient way to build simple, rectangular-shaped structures that utilize a series of embedded wood poles as the main structural support elements. If designed and constructed correctly, these buildings can be a viable approach for agricultural, residential, and commercial structures. Simplified lateral load design equations for embedded wood pole foundations are presented in this study, along with practical applications for use in simple building structures, to help with design feasibility and increased awareness of the viability of embedded wood pole structures for multiple occupancy uses. The equations address both the constrained and nonconstrained condition as presented in current international standards. The simplified lateral load design equations presented in this study are intended to be an aid to assist future designers that might potentially consider wood pole embedded construction. It is also intended to provide ideas for the constructive use of this method, utilizing these equations, as well as help designers avoid the shortfalls and challenges that exist with the currently provided standard equations. Equations for both the constrained and nonconstrained embedded pole condition are presented, which can be entered into a spreadsheet to facilitate easily produced, supporting design calculations. The case study’s solutions provided in this study were calculated in a similar manner using a spreadsheet. Such a design tool will nicely complement other design resources required for the complete evaluation and analysis of a wood pole building with embedded pole foundations. This study only focuses on the lateral design of the supporting foundations. Other conditions of the design (e.g., vertical or gravity loads, among others) would also need to be considered/evaluated.