JAWAHARLAL NEHRU TECHNOLOGICAL UNIVERSITY HYDERABAD B.Tech III Year II Semester IRRIGATION AND DRAINAGE ENGINEERING Previous Question Paper (April - 2018 - R15)

Define duty and write relationship among the duty, delta and base period.

Write classification of irrigation projects.

Define the irrigation scheduling.

What are the limitations in check basin method of irrigation?

Define weir and write the generalized equations for weirs.

Write about RBC flume.

Write the Hooghodut’s assumptions in deriving the spacing of drains.

Explain about the different outlets for sub surface drainage systems.

Define the leaching requirement.

Write about the soil amendments for reclamation of alkali soils.

If wheat requires about 7.5 cm of water after every 28 days, base period for wheat is 140 days, then find out the value of delta of wheat.

Explain about the soil moisture measurement by electrical resistance method.

Define the terms Field capacity, Permanent wilting point and Capillary water.

Write the procedure for measurement of infiltration by cylinder infiltrometer.

Explain about the Pressure plate technique method for soil moisture measurement.

Undisturbed soil sample was collected from a field two days after irrigation, when the soil moisture was near field capacity. The inside dimensions of the core sampler were 7.5 cm diameter and 15 cm deep. Weight of the core sampling cylinder with moist soil was 2.76 kg and the weight with oven dry soil was 2.61 kg. The weight of the core sampling cylinder was 1.56 kg. Determine the water depth in centimeters per metre depth of the soil.

Determine the infiltration depth in furrows by inflow-outflow method.

An irrigation stream of 27 lps is diverted to a check basin size 12 m × 10 m. The water holding capacity of the soil is 14%. The average soil moisture content in the crop root zone prior to applying water is 6.5%. How long should the irrigation stream be applied to the basin to replenish the root zone moisture to its field capacity, assuming no loss due to deep percolation. The average depth of crop root zone is 1.2 m. the apparent specific gravity of the root zone soil is 1.50.

Compute the gross depth of water application, the total number of irrigations and the irrigation interval of tomatoes of 5 months growing period in loamy soils. The irrigation water need of tomatoes for the whole growing period, estimated month wise is 720 mm (from table net depth of irrigation for tomatoes in loamy soils is 40 mm).

What is quarter-time rule, as applied to check basin irrigation.

The following data were obtained in determining the soil moisture content at successive depths in the root zone prior to applying irrigation water. The bulky density of the soil in the root zone was 1.50 gm/cc. The available moisture holding capacity of the soil was 17.8 cm/m depth. Determine i) the moisture content at different depths in the root zone, ii) moisture content in the root zone at the time of irrigation, iii) net depth of water to be applied to bring the moisture content to the field capacity, iv) gross irrigation requirement at an estimated field irrigation efficiency of 70 percent.

Explain about the underground pipeline structures.

Design an irrigation channel to carry 45 cumec of discharge by Kennedy’s method. The channel is to be laid out at slope of 1 in 4000. The critical velocity ratio (CVR) of the soil is 1.1. Use Cutter’s co-efficient n= 0.023. Assuming side slopes of the channel is 0.5:1.

Explain about standard test for irrigation pipes.

Write design procedure of Irrigation Channels by Kennedy’s Theory.

Derive the equation for hydraulic conductivity by inverse auger-hole method.

A watershed of 1500 hectares is discharging through a drain at an average rate of 2.5 m³/s. Calculate the drainage co-efficient, if the drainage coefficient is 3 cm, what would be discharge through the drain?

Explain about the different layouts of the subsurface drainage with neat sketches.

Determine the increase in drainage coefficient, if the rate of open ditch constructed for draining the watershed area of 1500 ha land, is increased from 5 to 10 m³/s.

Derive Ellipse equation for spacing of tile drains under steady state conditions with neat sketch.

Determine the soil load on a 300 mm clay drain tile installed at a depth of 250 cm in a trench of 50 cm wide assuming that the maximum weight of saturated top soil in the back fill is 1500 kg/m³. Calculate the design load using a safety factor of 1.5. What quality tile drain is required to withstand the design load if ordinary bedding conditions are provided?

Derive Ernst equation with neat sketch for steady state flow.

Determine the depth of irrigation water which would change a 20 cm depth of loamy soil root zone into saline conditions if the EC of irrigation water is 1.0 dS/m. Apparent specific gravity of the soil is 1.3 gm/cc and saturation percentage is 40%?