Traffic and Highway Engineering - With Mindtap
5th Edition
ISBN: 9781305360990
Author: Garber
Publisher: CENGAGE L
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Question
Chapter 21, Problem 4P
To determine
The suitable sketch showing the relationship between pavement condition and of time for service life.
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Check out a sample textbook solutionStudents have asked these similar questions
Assume that the overall pavement evaluation of Interstate highways in a district consists of four categories: Surface distress index = 75, drainage index = 80, roughness index = 85, and structural index = 90. For all indices, 100 represents the best condition. Calculate the overall pavement index (OPI) of the interstate highways in this district, if the relative weights of different indices are 0.20, 0.25, 0.28, and 0.27, respectively.
Q. 4
a) Why should the effective structural capacity of an existing pavement earmarked for
rehabilitation to extend its service life be evaluated?
b) The following expression is associated with the use of the Falling Weight Deflectometer
(FWD) on pavements earmarked for rehabilitation.
1.5pa
d, =
Mg
MR
%3D
E,
i.
What is the structural transformation required to make the use of the above expression
possible?
Which parameters in the expression relate to the transformation?
I1.
Identify the parameters in the expression which are obtained from the FWD test and briefly
III.
describe how the setup of the test enables those parameters to be obtained. [You may use
any relevant expression(s) or equation(s) to support your explanation.]
● Example
A pavement is subjected to the single-axle loads shown in the table below. Determine the ESAL
for a design period of 20 years using AASHTO EALF and assuming a growth rate of 4%
Solution
Axle
load
(kip)
12
14
16
18
Number
per day
200.0
117.4
84.5
61.4
Axle load
(kip)
20
22
24
26
Number
per day
ESAL= (ADT), (T) (T) (365) (G) (D) (L)
47.2
21.4
129
6.1
Axle load
(kip)
28
30
32
34
Number
per day
2.9
1.2
2100
0.7
0.3
Chapter 21 Solutions
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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
- Q1) If the traffic using the pavement grows at an annual rate of 4 present ,determine the design ESAL for 20 years, if ESAL for one year =78900?arrow_forwardSubject : Transportation Engineering Give me both a and b right solutions A 5 tonne wheel load is applied on a pavement and generates a surface deflection of 0.15 mm. (a) If the equivalent radius of tyre contact is 100 mm and Poisson’s ratio is 0.3, what is the pavement’s modulus of elasticity? (b) If the pavement is 125 mm thick, what is the vertical stress at the top of the subgrade?arrow_forwardProblem No. 1A flexible pavement for an urban interstate highway is to be designed using the AASHTO method to carry a design ESAL of 3 x 106. It is estimated that it takes about a week for water to be drained from within the pavement and the pavement structure will be exposed to moisture levels approaching saturation for 30% of the time. The following additional information is available: Elastic modulus of asphalt concrete = 450,000 psiResilient modulus of base material = 35,000 psiResilient modulus of subbase material = 15,000 psiCBR of subgrade material = 8arrow_forward
- Discuss various tests used for the quality of aggregate used in flexible pavements.arrow_forward2. Draw typical pavement deterioration curves for two types of pavements (A and B). Pavements A and B's lifespan are 20 and 40 years until they reach a failure threshold. The cost of constructing shorter life span pavement (A) is 5 million dollars per mile whereas the pavement with longer life span (B) costs 10 million dollars per mile. You have the option of using overlays to extend the life span of a pavement which may cost 1.5 million dollars per mile with expected lifetime of 10 years. When you consider total costs (assume no inflation), which pavement type would you choose?arrow_forward50 KPa is equivalent to: O A) 5x 10^6 N/m^2 O B) 5 x 10^5 N/m^2 O0 5 x 10^3 N/m^2 O D) 5 x 10^4 N/m^2 Concrete is required for a plain concrete pavement to be constructed in Southern Alberta. The pavement will be exposed to freezing, thawing, and deicers. If aggregates with a nominal maximum size of 20 mm are used, what is the minimum cement content per cubic meter of concrete as per the CSA Standard? OA) 320 kg O B) 335 kg OO 390 kg OD) 420 kg During Lab 5, the relative density of a coarse aggregate sample was determined. The sample of coarse aggregate was towel dryed to represent this moisture state: O A) OD B) Wet OC SSD O D) Air Dry When performing the slump test, each layer of concrete is rodded times as per CSA specifications: OA) 20 O B) 25 OO 30 O D) 12arrow_forward
- Q:Discuss various tests used for the quality of aggregate used in flexible pavements.arrow_forwardCompute the modulus of elasticity of pavement if the modulus of elasticity of subgrade is 15MPa with a stiffness factor of 0.50.arrow_forwardDesign a pavement for a rural interstate highway. The expected design ESAL is 13x106. The pavement structure is to consist of asphalt concrete with an elastic modulus of 400000psi, a granular base with an elastic modulus of 26000psi, and a granular subbase with an elastic modulus of 12000psi. The elastic modulus of the subgrade is 8000psi. It is estimated that it will take a week for water to drain from the pavement and that the pavement will be saturated about 15% of the time. Assume that a reliability level o about 90% is required and that the initial serviceability index is 4.2 and the final serviceability index is 2.5.arrow_forward
- Q11. The first step in the process of pavement management is to: a) establishing project priorities b) secure data about the condition of each pavement section in the system. c) establishing options d) forecasting performance e) none of the answers Q12. A 8000 lb is placed on a two tires of a locked-wheel trailer. At a speed of 52 mil/h, 800 lb is required to move the device. The surface type assuming that treaded tires were used is: a) smooth b) fine-textured, rounded c) fine - textured, gritty d) coarse - textured, rounded e) coarse - textured, grittyarrow_forwardThe AADTT of a 2-way (2-lane each way) highway is 10,000. The directional distribution may vary between 45 and 55% depending on season. The lane distribution may vary between 60 and 75%. The driving lane always carries more loads compared to the passing lane. The growth factor for the pavement is 3.5%. Based on the above information, calculate the design AADTT for the driving lane if the pavement service life is 20 years.arrow_forwardDESIGN OF A RIGID PAVEMENT Give a summary of rigid pavement design procedure by AASHTO method (1993), and describe the variables used in the method. Explain the CBR test; how to conduct the test and its purposes. Where are the usages of test results in practical applications? Explain its advantages and disadvantages. Determine the thickness of a rigid pavement (thickness of concrete slab) by using the data provided below: DATA PROVIDED: Cumulative 18kips ESAL = 5.000.000 Overall standard deviation = 0.3 Reliability = 95% Design serviceability loose =1.7 Drainage coefficient = 1 Load transfer coefficient = 3.2 Mean concrete modulus of rupture = 650 psi Elastic modulus of the concrete to be used = 5.000.000psi Results of CBR test on subgrade material in the laboratory (Table 1): 10. Standard force-penetration data.arrow_forward
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