Repair, Evaluation, Maintenance, and Rehabilitation Research Program. Mathematical Analyses of Landside Seepage Berms.
Abstract
This report describes a study that extends solutions for mathematical analysis of seepage berms presented in 'Investigation of Underseepage and Its Control Lower Mississippi River Levees,' Technical Memorandum 3-424, Vol 1, October 1956, US Army Engineer Waterways Experiment Station. A plot of the required seepage berm width, B, versus the ratio of the permeability of the berm to the top blanket, K, for various safety factors indicates B is very sensitive to K for K < or = 1. When the uplift safety factor varies from 1.5 at the landside levee toe to 1.0 at the landside seepage berm toe, the berm width is only slightly greater than that for a uniform safety factor of 1.0. If the uplift safety factor is greater than 1.0 at the berm toe, then as the top blanket becomes thinner, the berm width becomes longer. Thus, other methods of underseepage control should be investigated to determine whether they may be more economical. When the seepage berm is impervious, the berm width is a maximum. When the seepage berm is infinitely pervious, the berm width is a minimum. Therefore, seepage berms should be constructed of the most pervious soils available (with adequate provisions for control of surface erosion and internal piping) in the interest of economy. Because of the great difficulty in determining the permeability of the foundation, top blanket, and seepage berm, the mathematical solutions presented in this report should be used only as a guide to good engineering judgement. A range of permeability values should be used rather than average values.
Document Details
- Document Type
- Technical Report
- Publication Date
- Sep 01, 1984
- Accession Number
- ADA150014
Entities
People
- R. A. Barron