Drift ratio (Deta)

Displacement ကို height နဲ႕စားထားတာကို Drift ratio လို႕ေခၚတယ္



Story drift ratio
Story drift ကို story height နဲ႕စားထားကိုေျပာတာ
ပထမ Story နဲ႕ ကပ္လ်ပ္ story မွာရွိေနတဲ့ ျခားနားခ်က္ကို သူတို႕ႏွစ္ခုရဲ႕ height နဲ႕စားထားတာကို
ေျပာတာ။ (D2-D1)/(h)

Dxe and Dx ဆိုျပီးႏွစ္ခုရွိတယ္ တစ္ခုက Elastic ျဖစ္ျပီး တစ္ခုက inelastic ျဖစ္တယ္။
Dxe*cd/I
where I is important factor
Important factor ဆိုတာ လူေနထိုင္မူေပၚမူတည္ျပီး သက္မွတ္ထားတဲ့ factor ေတြကိုေျပာတာ
Cd က deflection amplification factor လို႕ေခၚတယ္ ASCE and IBC မွာရွိတဲ့ တန္ဖိုးေတြနဲ႕တြက္နုိင္။

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