Question

Assume we have one road section which has 3 lanes in both directions. If the Sf for both direction is 75 mph, and Dj for both direction is 200 veh/mi/ln. Estimate the S0, D0 (veh/mi/ln) and maximum Vm (veh/hr) for either direction.

Answer 1

Answer:

i) 3750 veh/hr/ln

ii) 100 veh/mi/In

iii) 37.5 mph

Explanation:

number of lanes = 3

sf for both directions = 75 mph  ( free mean speed )

Dj for both directions = 200 veh/mi/In

Calculate the value of  S0, D0 (veh/mi/ln) and maximum Vm (veh/hr)

For either direction we will consider the total volume = 3 lanes

value of Dj = 3 lanes * 200 = 600 veh/mi/

i) value of SO

=  ( Dj * sf ) / 4 = ( 600 * 75 ) / 4 = 11250 veh/hr  = 3750 veh/hr/lane

ii) Value of DO

DO = Dj / 2 = 200 /2 = 100 veh/mi/In

iii) Value of Vm

= sf /2 = 75 / 2 = 37.5 mph