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The Equilibrium super elevation is given by
V2R
V2gR V in Km/hr
V2gR V in Km/hr
V2127R
None of the above
V2127R
Equilibrium superelevation is the rate of superelevation that exactly neutralizes the centrifugal force acting on a vehicle by utilizing the component of gravity. When the vehicle weight and centrifugal force are balanced by the banking of the road, the pressure on the inner and outer wheels remains equal.
Equilibrium superelevation is the rate of superelevation that exactly neutralizes the centrifugal force acting on a vehicle by utilizing the component of gravity. When the vehicle weight and centrifugal force are balanced by the banking of the road, the pressure on the inner and outer wheels remains equal.
e=gRv2тАЛ тАФ Equilibrium superelevation (v in m/s)
e=127RV2тАЛ тАФ Equilibrium superelevation (V in km/hr)
The principle relies on the lateral force balance on a curved path. The centrifugal force is given by P=gRWV2тАЛ. To counteract this, the component of gravity Wsin╬╕ acts to pull the vehicle inward. Equilibrium is achieved when the centrifugal force component Pcos╬╕ equals the gravitational component Wsin╬╕. Since ╬╕ is small, tan╬╕тЙИsin╬╕тЙИe. Substituting V in km/hr leads to the conversion factor of 127.
Equilibrium superelevation eliminates lateral friction demand.
It is calculated specifically for the design speed.
IRC specifies limits for e to ensure safety for slow and fast-moving vehicles.
The constant 127 is derived from g├Ч3.62тЙИ9.81├Ч12.96тЙИ127.
Uniform distribution of pressure on wheels
Enhanced comfort for passengers on curves
Can be problematic for slow-moving vehicles on steep slopes
Requires significant construction precision
Design of horizontal curves on highways
Railway track banking to maintain stability
Option B is mathematically incomplete as it lacks the numerical conversion constant when using km/hr.
Option A represents the radial acceleration formula RV2тАЛ without gravitational or unit constants.
C is correct тАФ The equilibrium superelevation formula for velocity in km/hr is given by e=127RV2тАЛ.
Always verify units when dealing with Highway Engineering formulas; V in km/hr always results in a conversion constant like 127, whereas v in m/s uses g (9.81).