EngineeringKhaga · Class 6-8
Baandh ke teen roop: gravity, mitti aur mehraab
Kabhi socha hai ki har baandh ek jaisa kyun nahi dikhta? Kuch seedhi concrete ki deewar, kuch mitti-pattharon ka chauda teela, aur kuch pahaadon ke beech mude hue dhanush jaise. Engineer kaise chunte hain?
Socho pehle… phir dekho jawab
Engineer teen sawaal poochhte hain: neeche ki zameen kaisi hai, aas-paas kya saamaan milta hai, aur ghaati kitni chaudi hai. Jawab se baandh ka roop tay hota hai — par teeno ka kaam ek: badhte paani ke dabaav ko surakshit jhelna.
Gravity dam: concrete ya patthar ki bhaari deewar jo apne wazan se khadi rehti hai; katav tikona — neeche chauda kyunki paani ka dabaav gehrai ke saath badhta hai. Udaharan: Sutlej par Bhakra, ek concrete gravity dam. Majboot chattan wali neev chahiye.
Embankment (mitti/patthar bhara) dam: mitti aur pattharon ka bahut chauda teela, beech mein paani rokne wali kam-risaav mitti ki parat (core). Naram neev par bhi ban sakta hai aur aas-paas ka saamaan lagta hai, par paani deewar ke upar se behne lage toh mitti kat sakti hai — isliye bada spillway zaroori.
Arch dam: patli, mudi hui deewar jo dhanush ki tarah paani ka dhakka dono taraf ki pahaadi chattanon par dhakel deti hai. Sankari, chattani ghaati mein kam concrete mein kaam ho jaata hai.
Teeno ke saath: spillway (zyada paani ka surakshit raasta), risaav ki nigraani, aur niyamit jaanch. Kadi: zameen jaanchi, phir saamaan dekha, phir roop chuna, isliye har baandh apni jagah ke hisaab se alag dikhta hai.
Humne kya kiya :- Teen tarah ke baandh ko zameen, saamaan aur ghaati ki chaudai se joda.
Isse kya hua :- Samjhe ki design ek shape ratna nahi, jagah ke hisaab se sahi chunav hai — par paani ke dabaav ka niyam sabke peeche ek hai.
Ghar pe try karo
Thaali mein gili mitti se ek chauda teela-baandh banao, aur ek gatte ki patti ko mod kar dhanush (arch) baandh banao, jiske dono sire do bhaari kitaabon se tike hon (patti ke peeche plastic ki thaili rakh do). Dono ke peeche dheere paani daalo. Table: kaunsa tika, kahan risaav hua. Paani paudhon ko.
Wow!
Arch dam patla hote hue bhi majboot hai, kyunki woh paani ka dhakka khud nahi sehta — mod ke zariye dono taraf ki chattanon ko saunp deta hai!
3 sawaal
- Kaunsa baandh apne bhaari wazan se paani ka dhakka jhelta hai?
Jawab dekho
Gravity dam. Gravity dam apne wazan se khada rehta hai; Bhakra (Sutlej) iska udaharan hai.
- Arch dam kis tarah ki jagah ke liye sabse theek hai?
Jawab dekho
Sankari, majboot chattani ghaati. Arch dam dhakka dono taraf ki chattanon ko deta hai, isliye sankari chattani ghaati chahiye.
- Mitti ke (embankment) baandh ke liye sabse bada khatra kya hai?
Jawab dekho
Deewar ke upar se paani behna, jisse mitti kat jaaye. Overtopping se mitti kat sakti hai; isliye bada spillway zaroori hai.
NCERT se jodo: NCERT Class 8 Science — liquid ka dabaav; Class 10 Geography — jal sansaadhan aur bahuuddeshiya pariyojanaayein (idea in words)