This study will prepare an updated Tribal Long Range Transportation Plan and a strategic plan for improvements over five-, 10-, and 20-year periods, incorporating both roadway and multimodal needs. Some key focus areas of the Plan are road maintenance and safety programs, as well as improvement plans for bicycle, pedestrian, and transit systems. It also Identifies updates to the Tribal Transportation Inventory and functional classification systems will assist in expanding the level and types of funding available for transportation projects.

The 2009 Navajo Nation Long Range Transportation Plan is a twenty-year comprehensive plan developed and updated by the Navajo Division of Transportation in a five-year cycle. The plan identifies the Nation’s multi-modal transportation needs over the next 20 years and develops strategies to meet them. The plan provides long range planning policies and implementation strategies for the Navajo Indian Reservation Roads Program improvements. It is based on a comprehensive analysis of all pertinent factors and issues affecting the Navajo Nation’s existing and future transportation needs.

This report provides a simplified method to be used for evaluating the skin friction and tip resistance of axially loaded drilled shafts. A summary of literature and current practice was completed and then a comprehensive set of field and laboratory tests was performed. Several soil samples were collected from different sites from Arizona and surrounding states. Large scale direct shear apparatus was developed and used to determine the friction between soil and concrete. Finite element analyses were conducted on several prototype cases to determine effect of soil parameters such as dilation on the skin friction values. A step-by-step simplified approach was introduced to determine the skin and tip resistance of drilled shaft foundations in gravelly soils. An example application was presented to guide users in utilizing the simplified approach.