Over the past several years, Arizona policymakers have debated a number of immigration-related crime control policies. These discussions have ranged from arguments over the wisdom of granting local law enforcement agencies the authority to arrest and prosecute illegal aliens, to enacting legislation that sanctions employers for hiring illegal aliens. The perception that illegal aliens are responsible for a disproportionate amount of crime and violence in the state is at the root of many of these policy discussions. This report examines the connection between illegal aliens and crime in Maricopa County, Arizona, using data from the Arizona Arrestee Reporting Information Network.

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.