Traffic and Highway Engineering
5th Edition
ISBN: 9781305156241
Author: Garber, Nicholas J.
Publisher: Cengage Learning
expand_more
expand_more
format_list_bulleted
Question
Chapter 3, Problem 25P
To determine
(a)
The required minimum ramp radius of the expressway for the given conditions.
To determine
(b)
The required length of the ramp.
Expert Solution & Answer
Trending nowThis is a popular solution!
Students have asked these similar questions
A section of highway has a speed-flow relationship of the form q = au2 + bu. It is known that at capacity (which is 3100 veh/h) the space-mean speed of traffic is 28 mi/h. Determine the speed when the flow is 1500 veh/h and the free-flow speed.
A freeway is being designed to carry a heavy volume of 5000 veh/h on a regular weekday in rolling terrain. If the PHF is 0.9 and the traffic consists of 90% passenger cars and 10% trucks, determine the number of 12-ft lanes required in each direction if the highway is to operate at level of service C. The free-flow speed is 70 mi/h, there is no lateral obstruction, and interchanges are 3 mi apart.
Briefly describe the traffic characteristics associated with each of the levels of service for basic freeway sections.
Chapter 3 Solutions
Traffic and Highway Engineering
Knowledge Booster
Similar questions
- A section in SCTEX has a flow density relationship of q = 75k - 2.7k² where q is the flow and k is the density. what is the space mean speed if the density of the expressway is 15 veh/kmarrow_forwardEight lane urban freeway is on level terrain with lane width of 12 ft, right shoulder lateral clearance of 4 ft, and 12 ramps over the 6-mi analysis segment. The traffic stream consists of unfamiliar road users. Peak hour volume for a directional weekday of 3200 vehicles is observed with 900 vehicles arriving in the most congested 15-min period. If the traffic stream has 20% large trucks and 20% buses and 15% recreational vehicles, determine the density in pc/mi/In. Round your answer to 3 decimal places. Exclude the unit in the answer box.arrow_forwardProblem Determine the level of service? for six lanes undivided level highway. The width of lane, shoulder on the right side, and shoulder on the left side are 10 ft, 2 ft, and 2 ft respectively. The directional hour volume is 3500 Veh/h. The traffic composition includes 15% trucks and 1% RVs. The peak hour factor is 0.80. Unfamiliar drivers use the road that has 10 access points per mile. The design speed is 55 mi/h. Discuss possible modifications to upgrade the level of service? (Verify your answer)arrow_forward
- Q3. A new section of a freeway is to be designed with a free-flow-speed of 65 mph along of 0.75 mile on 5% upgrade. The expected traffic volume is 4200 v/hr. The traffic composition is 15% trucks, 5% recreational vehicles, and 10% buses. The peak hourly factor is 0.9, the unfamiliar driver factor is 0.95. If the design requirement is to target a level of service (B). how many lanes must be provided to satisfy the design requirement?arrow_forwardA divided multilane highway in a recreational area has four lanes (two lanes in each direction) and is on rolling terrain. The highway has 10-ft lanes with a 6-ft right-side shoulder and a 3-ft left-side shoulder. The posted speed is 50 mi/h. Previously, there were 4 access points per mile, but recent development has increased the number of access points to 12 per mile. Before development, the peak-hour factor was 0.95, and the directional hourly volume was 2200 vehicles with 13% heavy vehicles. After development, the directional hourly volume is 2600 vehicles with the same vehicle percentages and peak-hour factor. What is the LOS before and after the development?arrow_forwardAn existing urban freeway with 4 lanes in each direction has the following characteristics. Traffic data: Peak hour volume (in the peak direction): Trucks: PHF = 0.93 Geometric data: Lane width: Shoulder width: Total ramp density: Terrain: rolling 11 ft 6 ft 1.8 ramps per mile Determine the LOS in the peak hour. (Assume commuter traffic and assume no RVs.) LOS A LOS B LOS C LOS D LOS E LOS F mean speed density 7,010 veh/h 10% of peak hour volume Show the demand flow rate (in pc/h/In), mean speed (in mi/h), and density (in pc/mi/ln) for the given conditions. demand flow rate pc/h/In mi/h pc/mi/Inarrow_forward
- An undivided multilane highway segment has the following characteristics: • Six lanes (three lanes in each direction); Lane width of 11 ft; • Speed limit of 45 mph; Right shoulders is 4 ft wide; • There are approximately 25 access points over a 2-mile section of this roadway, in each direction. Calculate the FFS at this highway section and then determine the level of service (LOS) when the flow rate is 1100 pc/h/In. (Write the answer for the LOS in the box below).arrow_forwardOne segment of a Class I two-lane highway is on rolling terrain and has an hourly volume of 950 veh/h (total for both directions), a directional traffic split of 70/30, and PHF = 0.85, and the traffic stream contains 6% large trucks, 3% buses, and 6% recreational vehicles.arrow_forwardA 5% upgrade on a six-lane freeway (three lanes in each direction) is 1.25 mi long. On this segment of freeway, the directional peak-hour volume is 3800 vehicles with 2% large trucks and 4% buses (no recreational vehicles), the peak- hour factor is 0.90, and all drivers are regular users. The lanes are 12 ft wide, there are no lateral obstructions within 10 ft of the roadway, and the total ramp density is 1.0 ramps per mile. A bus strike will eliminate all bus traffic, but it is estimated that for each bus removed from the roadway, seven additional passenger cars will be added as travelers seek other means of travel. a.) What is density, before the bus strike? b.) What is the volume-to-capacity ratio, before the bus strike? c.) What is the level of service of the upgrade segment before the bus strike? d.) What is density, after the bus strike? e.) What is the volume-to-capacity ratio, after the bus strike? f.) What is the level of service of the upgrade segment after the bus strike?arrow_forward
- During the peak hour, an urban freeway segment has a traffic flow of 6,000 veh/h, with 4,000 vehicles with one occupant and 2,000 vehicles with two occupants. The freeway has five lanes, four of which are unrestricted opening to all vehicles regardless of vehicle occupancy and one lane that is restricted for use by vehicles with two occupants. Link performance functions for the length of this freeway segment are tu = 30+ 0.5vu for the unrestricted lanes and tr = 20+2vr for the restricted lane, where t’s are in minutes and v’s are in 1,000 vehicles. Solve for the distribution of traffic among the lanes using the SO principle and compare the savings in person hours relative to a UE solution, assuming that the compliance is perfect and that no single-occupant vehicles use the restricted lanes.arrow_forward55 mph roadway with two northbound through lanes (both are 11 feet in width) through an intersection. Beyond the intersection, the lanes merge into one lane. Please calculate the merge taper AND the distance the sign must be place AHEAD or upstream of the beginning of the merge. Pls hand written solutionarrow_forwardDetermine the total stopping distance (ft) for a road with speed limit of 79mph and grade of -2.5%arrow_forward
arrow_back_ios
SEE MORE QUESTIONS
arrow_forward_ios
Recommended textbooks for you
Traffic and Highway EngineeringCivil EngineeringISBN:9781305156241Author:Garber, Nicholas J.Publisher:Cengage Learning
Traffic and Highway Engineering
Civil Engineering
ISBN:9781305156241
Author:Garber, Nicholas J.
Publisher:Cengage Learning