TVA Cuts Deep Slot in Dam, Ends Cracking Problem

by Thomas J. Abraham, (M.ASCE), Head Civ. Engr. (Hydro Design); Tennessee Valley Auth., Knoxville, Tenn.,
Richard C. Sloan, (M.ASCE), Sen. Civ. Engr.; Tennessee Valley Auth., Knoxville, Tenn.,


Serial Information: Civil Engineering—ASCE, 1978, Vol. 48, Issue 1, Pg. 66-70


Document Type: Feature article

Abstract:

In 1972, cracking in the concrete dam at TVA's Fontana project embarked TVA on a four-year program of investigation, analysis and repair. Thermal expansion in the downstream face of the dam caused a longitudinal thrust that cracked the curved blocks near the left abutment. To retard cracking while a permanent solution could be devised, TVA sprayed reservoir water on the dam face to cool the concrete, pressure-grouted the crack and installed post-tensioned cable tendons to keep the crack from opening further. The final solution was to cut a vertical slot 100-ft deep across the dam to interrupt the longitudinal thrust. The slot was cut by drilling overlapping holes into the top and downstream face of the dam. Two flexible rubber seals prevented the water from entering the slot. Frequent monitoring of the dam shows the slot has solved the cracking problem.



Subject Headings: Cracking | Concrete dams | Cables | Dams | Thrust | Water pressure | Thermal properties

Services: Buy this book/Buy this article

 

Return to search