TVA Monograph No. 75, Chapter 9: Tests

The last chapter reports the tests that supported the designs. It begins with fill material tests, including the variation in the coefficient of internal friction at lower pressures, and notes that this may reflect differences in test samples and cohesion, which matter more at low pressure.

It also shows how the fill for the Hales Bar upstream cofferdam was handled: the designers used the Kentucky values for friction and unit weight and chose to remove fines by screening to get a free-draining fill, a process that may not be economical on large cofferdams but is worth checking with sieve analyses to estimate the saturation line in the cells.

The chapter closes with the test cell for the Kentucky cofferdam, which gave measurements of how a real cell behaved. Together with the field measurements covered in the WES manual, it gives a useful record of how theory compared with practice.