Date of Award


Degree Type


Degree Name

Master of Science (MS)


Civil and Environmental Engineering

First Advisor

John Rice

Second Advisor

James A. Bay

Third Advisor

Gilberto Urroz


Piping is a form of internal erosion in which soil particles are eroded at a seepage exit location due to the forces imposed on the particles by seeping water. Laboratory testing was performed on a variety of soils in order to assess a correlation between unit weight, angle of internal friction, grain size, gradation, and void ratio and the critical hydraulic gradient at which piping initiates and progresses. A multi-variable regression analysis was used to form equations to predict critical hydraulic gradient based upon each of these soil parameters. Variations in the accuracy of these equations are thought to be due to the interlocking behavior of the angular soils tested compared to that of the more spherical soils as well as the loosening of the sample and change in void ratio as piping progresses.