1.The vertical effective stress at a certain point in a loose sand is 1000lb/ft^2. If an earth quake were to occur, how much excess pore water pressure would need to develop at this point for liquefaction to occur? Show a numerical rationale for your answer.
2.Compute the 50 year flood discharge on a large creek in Northern Ohio if the total discharge area is 75 mi^2. The average soil infiltration is 0.5 in./hr; the main channel slope is 0.008. (The rain fall intensity is 14.)
3.A 2.5 hr long uniform rainfall resulted in runoff hydrograph that has the shape of an equilateral triangle. The base of the triangle is 64 hr; the peak flow is 535 cfs; the drainage area is 5.7 mi^2. Determine the corresponding unit hydrograph if the base flow for the channel is 10 cfs.
4.A 300-acre forested watershed in fair hydrologic condition located on the clayey flat coastal region of Southern California receives 4.0 in. of rain in a 24 hr period. Determine the corresponding flood peak of the runoff using the SCS curve number method.