PRIN.OF HIGHWAY ENGINEERING&TRAFFIC ANA.
7th Edition
ISBN: 9781119610526
Author: Mannering
Publisher: WILEY
expand_more
expand_more
format_list_bulleted
Concept explainers
Question
Chapter 8, Problem 27P
To determine
The user equilibrium flows and total hourly origin-destination demand after the capacity improvement.
Expert Solution & Answer
Want to see the full answer?
Check out a sample textbook solution
Students have asked these similar questions
8.21 Three routes connect an origin and destination with performance functions t₁ = 2 +0.5x₁,₂ = 1 + x2 and 13 = 4 + 0.2x, (with f's in minutes and x's in thousands of vehicles per hour). Determine user- equilibrium flows if the total origin-to-destination demand is (a) 5000 veh/h.
Two routes connect an origin-destination pair with performance functions t₁ = 5 + (x₁/2)² and t₂ = 7+ (x2/4)² (with t's in minutes and x's in thousands of vehicles per hour). It is known that at user equilibrium, 75% of the origin-destination demand takes route 1. What percentage would take route 1 if a system-optimal solution were achieved, and how much travel time would be saved?
3. Three routes connect an origin-destination pair with performance functions:
ti=20 +0.51
t₂ = 4+2x2
tε = 3 +0.2x²
with t in minutes and r in thousand vehicles per hour.
(a) Determine the User Equilibrium flow on each route if q = 4000veh/h.
(b) What is the minimum q (origin-destination demand) to ensure that all the three routes are used
under user equilibrium?
(c) Suppose that Route 1 is closed for repair. Find the system optimal flow on routes 2 and 3 and
compute the total travel times.
Chapter 8 Solutions
PRIN.OF HIGHWAY ENGINEERING&TRAFFIC ANA.
Ch. 8 - Prob. 1PCh. 8 - Prob. 2PCh. 8 - Prob. 3PCh. 8 - Prob. 4PCh. 8 - Prob. 5PCh. 8 - Prob. 6PCh. 8 - Prob. 7PCh. 8 - Prob. 8PCh. 8 - Prob. 9PCh. 8 - Prob. 10P
Ch. 8 - Prob. 11PCh. 8 - Prob. 12PCh. 8 - Prob. 13PCh. 8 - Prob. 14PCh. 8 - Prob. 15PCh. 8 - Prob. 16PCh. 8 - Prob. 17PCh. 8 - Prob. 18PCh. 8 - Prob. 19PCh. 8 - Prob. 20PCh. 8 - Prob. 21PCh. 8 - Prob. 22PCh. 8 - Prob. 23PCh. 8 - Prob. 24PCh. 8 - Prob. 25PCh. 8 - Prob. 26PCh. 8 - Prob. 27PCh. 8 - Prob. 28PCh. 8 - Prob. 29PCh. 8 - Prob. 30PCh. 8 - Prob. 31PCh. 8 - Prob. 32PCh. 8 - Prob. 33PCh. 8 - Prob. 34PCh. 8 - Prob. 35PCh. 8 - Prob. 36PCh. 8 - Prob. 37PCh. 8 - Prob. 38PCh. 8 - Prob. 39P
Knowledge Booster
Learn more about
Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, civil-engineering and related others by exploring similar questions and additional content below.Similar questions
- Three routes connect an origin to a destination with the following link performance functions: t_1 = 8 + 0.5 x_2 t_2 = 1 + 2x_2 t_3 = 3 + 0.75x_3 where t's in minutes and x's in thousands of vehicle per hour. If the peak-hour traffic demand is 4000 vehicles, determine the user equilibrium (UE) flows.arrow_forwardhree routes connect an origin and a destination with performance functions: ?1=8+0.5?1; ?2=1+2?2; and ?3=3+0.75?3; with the x’s being the traffic volume expressed in thousands of vehicles per hour and t’s being the travel time expressed in minutes. If the peak hour traffic demand is 3400 vehicles, determine user equilibrium traffic flows. [Hint: Note that one of the paths will not be used under the equilibrium conditionarrow_forward8.18 Two routes connect an origin and a destination. Routes 1 and 2 have performance functions t₁ = 2 + x₁ and t₂ = 1 + x2, where the 's are in minutes and the x's are in thousands of vehicles per hour. The travel times on the routes are known to be in user equilibrium. If an observation for route 1 finds that the gaps between 30% of the vehicles are less than 6 seconds, estimate the volume and average travel times for the two routes. (Hint: Assume a Poisson distribution of vehicle arrivals, as discussed in Chapter 5.)arrow_forward
- 8.25 Two routes connect an origin and destination with performance functions t₁ = 5 + 3x₁ and t₂ = 7+ X2, with t's in minutes and x's in thousands of vehicles per hour. Total origin-destination demand is 7000 vehicles in the peak hour. What are user- equilibrium and system-optimal route flows and total travel times?arrow_forwardTwo routes connect an origin and destination with performance function t; = aj + (xj/cj)2 (with t's in minutes and x's in thousands of vehicles per hour). It is known that at user equilibrium, 65% of the origin-destination demand takes route 1. How many vehicles (in thousands) will take route 1 if system optimal equilibrium is archived? Route 1 Route 2 a 7 2 3arrow_forwardTwo routes connect a city and suburb. During the peak-hour morning commute, a total of 5000 vehicles travel from the suburb to the city. Route 1 has a 50km/hr speed limit and 5km in length, Route 2 has a 55km/hr speed limit and 4 km in length. Studies show that the total travel time on route 1 increases 2 mins for every extra 500 vehicles added. Mins of travel time on route 2 increase with the square of the no. of vehicles expressed in 000’s. Determine user equilibrium travel times.arrow_forward
- 8.5 If small express buses leave the origin described in Example 8.5 and all are filled to their capacity of 20 travelers, how many work-trip vehicles leave from origin to destination in Example 8.5 during the peak hour?arrow_forward4. Three routes connect and origin and a destination with performance functions t₁ = 8 + x₁, t₂ = 1 + 2x₂, and t3 = 1 + 0.5x3 (with x's in thousands of vehicles per hour and t's in minutes). If the peak-hour traffic demand is 3400 vehicles, determine user- equilibrium traffic flows on each route. [Ans: x₂ = 0.68]arrow_forwardto no congestion on the road further downstream of the railway grade crossing. QUESTION 5: Consider trip distribution within 5 zones in an area. The total trip production from zone 1 is 1000. The travel times from zone 1 to zones 2, 3, 4 and 5 are 5, 10, 20, and 30 minutes, respectively. The trip attraction to zones 2, 3, 4 and 5 are 50, 200, 75, and 450, respectively. Assume that the number of trips produced from zone 1 to zones 2, 3, 4 and 5 is inversely proportional to the inter-zonal travel time. (a) Estimate the number of trips from zone 1 to zones 2, 3, 4 and 5 using the gravity model. (b) Assume that the future trip production from zone I will increase to 1,250 and the future trip attraction to zones 2, 3, 4 and 5 will increase to 100, 225, 100, and 600, respectively. Predict the number of trips from zone 1 to zones 2, 3, 4 and 5. The inter-zonal travel times remain the same. (c) Compare the number of trips from zone 1 to each destination zone between (a) and (b). Identify the…arrow_forward
- Suppose that the projected road vehicle traffic flow in a corridor is 5000 vehicle-trips per hour in one direction. The average perceived user cost functions of the two major highways (Route 1 and Route 2 in the corridor are as follows (in dollars): Route 1: Ci =1 +8(qı/5000) Route 2: C2 = 1+10(q2/2500) Where: qi and q2 are the traffic flows on Route 1 and Route 2 respectively. Calculate the volume of traffic during the peak hour on each route, if users were free to choose their own routes.arrow_forwardThe daily counts of the current traffic volume for a rural highway for one week of May 2000 are as shown in the following table: Sat. Sun. Mon. Tues. Wed. Thur. Fri. Day Daily volume 12000 12500 10500 11500 9500 9000 8500 The traffic is composed of 70% passenger car, 20% bus, 10% truck. The percent of future traffic to current traffic is predicted to be 180% up to May 2020. Determine the required number of lanes for this highway if the lane capacity is 1300 pc/hr.arrow_forwardExample: A busy travel corridor connecting a suburb with the city center is served by two routes having a typical travel time function, t =a + b(q/c), where t is the time in minutes, q is the vehicular flow in veh/hr, and c is the capacity of the route in veh/hr. The existing characteristics of the two routes is as follows: Route a b c 1 34 3000 2 4 2 4000 (a) If the existing peak-hour demand is 5000 veh/hr, what is the traffic distribution on the two routes? (b) If repair work on Route 1 reduces its capacity to 2000 veh/hr, what is likely to be the traffic distribution on the two routes for the duration of the repairs? (c) It is anticipated that after the repairs are completed on Route 1, its capacity will be 4200 veh/hr. How will this affect the distribution.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