A flexible pavement is constructed with 5 inches of hot mix asphalt wearing surface (material coefficient = 0.4), 10 inches of granular base (material coefficient 0.11 and resilient modulus = 22,500 psi), and 12 inches of granular subbase (material coefficient = 0.09 and resilient modulus = 12,500 psi). The subgrade has a resilient modulus of 5,000 psi. The drainage coefficients are 0.9 and 0.8 for the base and subbase, respectively. The reliability factor is 90%, the overall standard deviation is 0.45, P; = 4.5 and P= 2.5. Determine the maximum 18,000 lb ESAL applications that can be carried safely by this pavement structure. %3D %3D %3D %3D %3D

A flexible pavement is constructed with 5 inches of hot mix asphalt wearing surface (material coefficient = 0.4), 10 inches of granular base (material coefficient 0.11 and resilient modulus = 22,500 psi), and 12 inches of granular subbase (material coefficient = 0.09 and resilient modulus = 12,500 psi). The subgrade has a resilient modulus of 5,000 psi. The drainage coefficients are 0.9 and 0.8 for the base and subbase, respectively. The reliability factor is 90%, the overall standard deviation is 0.45, P; = 4.5 and P= 2.5. Determine the maximum 18,000 lb ESAL applications that can be carried safely by this pavement structure. %3D %3D %3D %3D %3D

Structural Analysis

6th Edition

ISBN:9781337630931

Author:KASSIMALI, Aslam.

Publisher:KASSIMALI, Aslam.

Chapter2: Loads On Structures

Section: Chapter Questions

Problem 1P

See similar textbooks

Similar questions

How sensitive are the critical pavement responses to (a) increased tire pressure, (b) increased subgrade strength, (c) Poisson’s ratio changes, (d) lime stabilization of top 6 in. of subgrade, (e) asphalt or cement stabilization of base layer, etc
07. Determine Structural Number and terminal serviceability index value of flexible pavement. Given B and G, value for 32-kip tandem-axle loads. B= 0,4 G= -0.22
17. In the Asphalt Institute flexible pavement design approach, Where are the critical stress and strain locations checked?a. Top of the asphalt concrete layerb. Middle of the asphalt concrete layerc. Bottom of the asphalt concrete layerd. Bottom of the asphalt concrete layer and top of the subgrade
A pavement consists of 5 inches of asphalt underlain by a crushed stone based course. There is no sub base. The asphalt has an elastic modulus of 350,000 psi at room temperature and the base course has a CBR of 70. Determine the thickness of the crushed stone base needed to reach an SN of 2.85. Assume the base course is saturated 5% of the time and drains within a day.
12. Refer to Figure II-1 attached. A flexible pavement is to be evaluated according to the AASHTO 1972 design guide. The existing pavement has a weighted structural number=3.4, a regional factor=2.0, and a soil support value=4.5. What would be the approximated number of daily equivalent 18-kip axles to be allowed on this road for a 20-year analysis period?a. 10b. 33c. 100d. 1490
A rigid pavement is designed with an 11-inch slab thickness, 90% Rellability (ZR = -1.282), Es = 4 million psi, modulus of rupture of 600 psi, modulus of subgrade reaction of 150 lb/in?, a 2.8 load transfer coefficient, initial PSI = 4.8, final PSI of 2.5, overall standard deviation of 0.35, and a drainage coefficient of 0.80. The pavement has a 20-year design life. The pavement has three lanes in one direction (PDL = 0.80) and is conservatively designed for trucks that have one 20,000-lb single axle load (1.58), one 26,000-lb tandem axle (0.619), and one 34,000-b triple axle (0.593). What is the daily estimated truck traffic on the three lanes? logia (APSI) S,C¢(D@7% – 1.132) 3.0 [1.62410x10 |(D + 1)*46 | log10 (W) = Zg5, + 7.35 (log,0( D + 1)) – 0.06 +: +(4.22 - 0.327SI) log10 1+ 18.42 215.63/ De75 - 0.25
2. You are asked to design a new flexible pavement structure for an existing road that will be totally replaced. You are provided with the following borehole results: a) Existing (Old) HMA - 135 mm b) Existing (Old) Granular A Base - 170 mm c) Existing (Old) Granular B Subbase - 340 mm d) Gravelly Silty Sand (Till) Subgrade (25 % 5-75 um) What is the current GBE for the existing pavement structure? What is the GBE for the same pavement structure when it was newly constructed?
1. During the AASHO road test, ONLY flexible pavements were constructed and tested.a. Trueb. False2. The AASHO present serviceability rating (PSR) was considered an objective quantity used to establish the performance of highway pavement in terms of applied traffic.a. Trueb. False3. The AASHTO present serviceability index (PSI) correlates the PSR to actual pavement performance in terms of applied traffic, and select distresses.a. Trueb. False4. There is only one AASHTO PSI equation that applies to both flexible and rigid pavements.a. Trueb. False5. The AASHTO PSI scale ranges from:a. 0-5b. 0-10c. 0-100d. None of the above
B. A rigid pavement with a 10-inch slab thickness, 90 percent reliability, E. = 4 million lb/in², 600 lb/in² modulus of rupture, 150 lb/in³ modulus of subgrade reaction, a 2.8 load transfer coefficient, initial PSI of 4.8, final PSI of 2.5, overall standard deviation of 0.35, and a drainage coefficient of 0.8 is designed. The pavement's design life is 20 years. The three-lane road is built for vehicles with one 20,000-pound single axle, one 26,000-pound tandem axle, and one 34,000-pound triple axle. Calculate the projected daily truck traffic on the three lanes.
Select one for each of the following: 1. Tire pressure affects the: a) pavement thickness b) quality of surface course 2. Tie bars in rigid pavements are at: a) expansion joints 3. The fundamental factor in selection of pavement type is a) climatic condition b) type and intensity of traffic c) subgrade and drainage condition d) cost 4. Present Serviceability Index (PSI) depends on a) slope variance 5. Using subbase course in rigid pavement is for: a) resist unlimited loading b) more economical c) drainage purpose d) no reinforcement used c) number of layers d) pavement type b) contraction joints c) warping joints d) longitudinal joints b) rutting c) cracking d) all of them