A raft foundation of 30 m $$\times$$ 25 m is proposed to be constructed at a depth of 8 m in a sand layer. A 25 m thick saturated clay layer exists 2 m below the base of the raft foundation. Below the clay layer, a dense sand layer exists at the site. A 25 mm thick undisturbed sample was collected from the mid-depth of the clay layer and tested in a laboratory oedometer under double drainage condition. It was found that the soil sample had undergone 50% consolidation settlement in 10 minutes. The time (in days) required for 25% consolidation settlement of the raft foundation will be ___________. (round off to the nearest integer)
A two-hour duration storm event with uniform excess rainfall of 3 cm occurred on a watershed. The ordinates of streamflow hydrograph resulting from this event are given in the table.
| Time (hours) | 0 | 1 | 2 | 3 | 4 | 5 | 6 | 7 |
|---|---|---|---|---|---|---|---|---|
| Streamflow (m$$^3$$/s) | 10 | 16 | 34 | 40 | 31 | 25 | 16 | 10 |
Considering a constant baseflow of 10 m3/s, the peak flow ordinate (in m3/s) of one-hour unit hydrograph for the watershed is ____________. (in integer)
During a particular stage of the growth of a crop, the consumptive use of water is 2.8 mm/day. The amount of water available in the soil is 50% of the maximum depth of available water in the root zone. Consider the maximum root zone depth of the crop as 80 mm and the irrigation efficiency as 70%. The interval between irrigation (in days) will be ___________. (round off to the nearest integer)
In the context of cross-damage structures, the correct statement(s) regarding the relative positions of a natural drain (stream/river) and an irrigation canal, is/are