The practice job and how to run it
In practice you do a complete small job: understand it, prepare, build, check, and report. Our job is a farm road of 100 m, 3 m wide, with a side drain.
- Read the drawing and the needs.
- Set out the work on the ground.
- Count materials, people and cost.
- Build part by part.
- Check quality and safety all the time.
- Hand over with a short report and photos.
Setting out: pegs and string
Setting out means marking the plan on the ground. Drive pegs where the road edges and drain go, and tie a string between them tight and straight. Measure with a tape and check right angles (the 3-4-5 triangle works: sides 3 m, 4 m, 5 m make a right angle). A level or a clear water tube tells you the heights.
Earthwork and gravel layer
Work in parts of 20 m so you can finish, check, and move on. Shape the road bed with a slight slope (crown) so rain runs into the drain. Dig the drain so water flows away downhill. Press the soil. Spread gravel 0.15 m thick and press again with a roller or rammer.
Gravel volume = length × width × thickness = 100 × 3 × 0.15 = 45 m³ (a little more is ordered because loose stone shrinks when pressed).
People, days and cost
Suppose the whole job needs 40 worker-days (one person working one day = 1 worker-day).
- Days = worker-days ÷ number of workers. With 8 workers: 40 ÷ 8 = 5 days.
- Material cost = volume × price per m³. With gravel at ₹900 per m³: 45 × 900 = ₹40,500.
- Add labour, machine hire and a small allowance for waste for the total.
More workers finish sooner, but too many in a small space get in each other's way and can be unsafe.
Quality check
Check at every part, before moving on:
- Level and slope: with a level and a straight edge.
- Thickness: push a marked stick into the gravel layer.
- Compaction: the surface does not move or leave deep prints when walked on.
- Drain flow: pour water and see if it runs away.
Write the result in a log book. A part that fails is fixed first.
Safety on site
- Wear shoes, gloves and a hat or helmet.
- Keep cones or ribbon around the work.
- Keep children and animals away.
- Lift loads with a straight back, share heavy loads.
- Keep drinking water and shade for hot days.
- Keep tools in order. Stop work in heavy rain or lightning.
Try it: mini road in the garden
With a friend, mark a 5 m line with two sticks and a string. Dig a shallow strip 0.5 m wide, press it, spread a thin layer of small stones, and press again. Measure length, width and thickness, work out the volume, and write one safety rule you followed.
Key formulas and definitions
- Volume = length × width × thickness
- Days = total worker-days ÷ number of workers
- Material cost = volume × price per m³
- 3-4-5 triangle gives a right angle
- Order: Set out, Shape, Stone, Test, Secure
Worked examples
1. A road is 100 m long, 3 m wide, with a 0.15 m gravel layer. How much gravel?
100 × 3 × 0.15 = 45 m³.
2. The job needs 40 worker-days. How many days with 8 workers?
40 ÷ 8 = 5 days.
3. Gravel costs ₹900 per m³. What is the cost of 45 m³?
45 × 900 = ₹40,500.
4. A 60 m road, 2.5 m wide, with a 0.2 m layer. Volume?
60 × 2.5 × 0.2 = 30 m³.
5. A job needs 36 worker-days. You want it done in 4 days. How many workers?
36 ÷ 4 = 9 workers.
6. You measure 3 m, 4 m and 5 m on the ground and the corner is right-angled. Why?
Because 3² + 4² = 9 + 16 = 25 = 5². By Pythagoras the angle opposite the 5 m side is 90°.
Common mistakes
- Skipping setting out and building by eye, so the road bends.
- Ordering exactly the calculated gravel. Loose gravel shrinks when pressed, so a little extra is needed.
- Moving to the next part before checking the last one.
- Forgetting the drain. Water stays and softens the road.
- Mixing up worker-days and days: days = worker-days ÷ workers.