EngineeringKhaga · Class 6-8
Expressway ka design: ginti se lane tak
Ek hi sadak par cycle, scooter, car aur truck chalte hain. Engineer kaise tay karte hain ki sadak kitni chaudi ho?
Socho pehle… phir dekho jawab
Woh sab gaadiyon ko ek common unit mein badalte hain — PCU (passenger car unit). NHAI ke naye niyam: 15,000 PCU tak 4 lane; 15,000-25,000 par 4 lane sadak, lekin pul jaise structures 6 lane ke; 25,000-40,000 par 6 lane.
PCU kyun? Ek truck ek car se zyada jagah aur zyada samay leta hai, toh use ek car ginna galat hoga. PCU mein sab gaadiyon ko 'kitni car ke barabar' mein badal ke kul traffic nikalte hain. Engineer yeh bhi ginte hain ki naya expressway bana toh doosri sadakon se kitna traffic idhar aayega aur kitna naya banega — aur yeh andaaza toll ke data se check hota hai.
Access control: expressway par koi chauraha (at-grade intersection) nahi — aana-jaana sirf ramp se. Chauraahe par alag-alag disha ki gaadiyon ke raaste katte hain, isliye use hata diya. Gaon ke khet na kat jaayein, isliye harvester aur bhare tractor ke liye 4.5 m ooncha underpass; bhari aabaadi wale hisson mein dono taraf service road aur naali-cum-footpath.
Aur: bina barrier wala toll (MLFF), kinaare par 1 m ki RCC deewar taaki koi sadak ki zameen par kabza na kare, aur beech ke divider mein drip irrigation ke saath ped.
Ghar pe try karo
School ke gate ke andar se, kisi bade ke saath, 5 minute traffic gino: cycle, scooter, car, bus/truck. Maano (sirf example ke liye) scooter = 0.5, car = 1, bus/truck = 3 PCU. Kul PCU nikalo aur ek ghante ka andaaza lagao.
Wow!
Naye niyam mein 4 lane sadak par bhi pul 6 lane ke ho sakte hain — kyunki sadak chaudi karna aasaan hai, pul chauda karna nahi.
3 sawaal
- 15,000 se 25,000 PCU ke liye naya niyam kya kehta hai?
Jawab dekho
4 lane sadak par 6 lane ke structures (jaise pul). Is range mein sadak 4 lane, par structures 6 lane ke.
- At-grade intersection ka matlab kya hai?
Jawab dekho
Sadak ke level par hi chauraha, jahan raaste katte hain. At-grade = usi level par; expressway par aisa chauraha nahi hoga.
- 4.5 m ooncha underpass kiske liye?
Jawab dekho
Harvester aur bhare tractor ke liye. Jahan harvester aur bhare tractor chalte hain, wahan 4.5 m underpass.
NCERT se jodo: NCERT Class 7 Geography (Our Environment) — human environment: transport aur communication