1. ?Consolidation / time problem
0 to 20 ft??????? Clay, cv = 5 ft2/yr, calculated total settlement = 1.00 inches
20 to 30 ft????? Pervious sand
30 to 60 ft????? Clay, cv = 10 ft2/yr, calculated total settlement = 0.75 inches
60 ft + ????????? Very impervious shale.
On a single (arithmetic) graph, plot the settlement vs. time curves for the upper clay, lower clay, and their combined settlement. Pay attention to the lengths of drainage paths, and use appropriate scales.
For each layer, calculate the times for (say) 20, 40, 60, 80 and 90 percent consolidation.
Calculate the settlement for each layer at each time as S(t) = Sfinal x Uavg
Choose a scale that best fits the ?most? of the data, and plot the two curves. Then add them graphically. As this is settlement, the S axis is drawn positive downward.
To simplify grading, also report the approximate settlements of each layer, and the total settlement, at t = 20 years.