An infinite slope is made up of cohesionless soil with seepage parallel to and up to the sloping surface. The angle of slope is 30° with respect to the horizontal ground surface. The unit weights of the saturated soil and water are 20 kN/m3 and 10 kN/m3, respectively.
The minimum angle of shearing resistance of the soil (in degrees) for the critically stable condition of the slope is ________________ (rounded off to the nearest integer).
A soil sample was consolidated at a cell pressure of 20 kPa and a back pressure of 10 kPa for 24 hours during a consolidated undrained (CU) triaxial test. The cell pressure was increased to 30 kPa on the next day and it resulted in the development of pore water pressure of 1 kPa. The soil sample failed when the axial stress was gradually increased to 50 kPa. The pore water pressure at failure was recorded as 21 kPa. The value of Skempton's pore pressure parameter B for the soil sample is ________________ (rounded off to 2 decimal places).
The ordinates of a 1-hour unit hydrograph (UH) are given below.
| Time (hours) | 0 | 1 | 2 | 3 | 4 | 5 |
|---|---|---|---|---|---|---|
| Ordinates of 1-hour UH (m3/s) | 0 | 13 | 50 | 80 | 95 | 85 |
| Time (hours) | 6 | 7 | 8 | 9 | 10 | 11 |
|---|---|---|---|---|---|---|
| Ordinates of 1-hour UH (m3/s) | 55 | 35 | 15 | 10 | 3 | 0 |
These ordinates are used to derive a 3-hour UH. The peak discharge (in m3/s) for the derived 3-hour UH is ___________ (rounded off to the nearest integer).
A spillway has unit discharge of 7.5 m3/s/m. The flow depth at the downstream horizontal apron is 0.5 m. The tail water depth (in meters) required to form a hydraulic jump is ___________ (rounded off to 2 decimal places).