The existing posted speed limit on a section of highway is 55 mi/h and studies have shown that the current 85th percentile speed is 65 mi/h. If the poster speed limit is to be increased to the current 85th percentile speed, what should he the increase in the radius of a curve that is just adequate for the existing posted speed limit? Assume superelevation rate of 0.08 for the existing curve and for the redesigned curve.?

For the Greenshields model, the mean free flow speed on a highway facility lane equals 75 mph near zero density, and the jam density is observed to be about 160 veh/mi. Plot the q-k-u curves in proper order. Write down the speed-density, flow-speed, and flow-density equations. Find out the maximum flow, and also mark it on your diagrams. Compute speeds and densities corresponding to a flow of 2,880 veh/h, describing traffic conditions from a driver’s point of view. Calculate average headways, gaps, clearance, and spacing at CASE 1: maximum flow and at CASE 2: jam density. (Suppose the average vehicle length is 17ft)

A traffic stream is moving at a steady state when entering a mountain grade. Upon entering the grade, the speed, density and flow are 72 km/h, 25 veh/km and 1800 veh/hr respectively. On the grade, a truck drops to a speed of 15 km/h causing traffic to bunch up to a density of 85 veh/km. When the truck pulls over, traffic accelerates to the maximum flow until steady state flow conditions resume. Calculate (a) the flow of traffic behind the truck on the mountain grade (b) the jam density and free flow speed for this road (c) the density and speed when traffic resumes a steady state flow (d) the maximum flow

A developer has applied for a construction permit to build a supermarket at the southeast cornerof an intersection that is formed by a four-lane divided highway in the east-west direction and atwo-lane road in the north-south direction. Traffic on the two-lane road is controlled by a stop signat the intersection. The speed limit on the four-lane highway is 88 km/h. using the sight trianglerequirements at the intersection (Case B1), determine whether permission should be given for theconstruction if the following conditions exist. Provide a diagram for your solution.Major road lane width = 3.6 mMinor road lane width = 3.3 mMedian lane = 2.8 mDesign vehicle is a passenger carApproach grade = 2%Maximum feasible distance building from the center of the nearest lane of four-lane road = 5.4 mMaximum feasible distance building from the center of the nearest lane of two-lane road = 16.5 m

A temporary diversion has been constructed on a highway of -3% gradient due to major repairs that are being undertaken. Determine the speed limit that should be imposed on the diversion if drivers can see the sign inform ing them of the diversion at a distance of 400 ft from the diversion and the posted speed limit on the highway is 60 mph.