Three primary factors in considering the loads on, and therefore the design of, underground conduits are: bedding conditions, trench configuration, and use of the "imperfect trench." Models of varied conditions are analyzed using a finite element program and the results compared to data obtained at instrumented sites of similar conditions. Presented herein are charts developed from these analyses which will facilitate future design of culverts. Also presented are recommendations for design criteria and construction procedures.

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The contents of this report reflect the views of the authors who are responsible for the facts and the accuracy of the data presented herein. The contents do not necessarily reflect the official views or policies of the Kentucky Transportation Cabinet, the Federal Highway Administration, nor the University of Kentucky. This report does not constitute a standard, specification, or regulation.