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A rigid pavement is on a highway with two lanes in one direction, and the pavement is conservatively designed. The pavement has an 11-inch slab with a modulus of elasticity of 5,000.000 lb/in2 and a concrete modulus of rupture of 700 lb/in2, and it is on a soil with a CBR of 25. The design drainage coefficient is 1.0, the overall standard deviation is 0.3, and the load transfer coefficient is 3.0. The pavement was designed to last 20 years (initial PSI of 4.7 and a final PSI of 2.5) with 95% reliability carrying trucks with one 18-kip single axle and one 28-kip tandem axle. However, after the pavement was designed, one more lane was added in the design direction (conservative design still used), and the weight limits on the trucks were increased to a 20-kip single and a 34-kip tandem axle (the slab thickness was unchanged from the original two-lane design with lighter trucks). If climate change has caused the drainage coefficient to drop to 0.8, how long will the pavement last with the new loading and the additional lane (same volume of truck traffic? For thickness, please round-off to the nearest ¼ inch if necessary.

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- I will dislike and report if once again i will get wrong answerarrow_forwardA flexible pavement is constructed with 3 inches of hot-mix asphalt (HMA) wearingsurface, 6 inches of emulsion/aggregate-bituminous base, and 6 inches of crushedstone subbase. The subgrade has a soil resilient modulus of 8,000 lb/in2 , and M2 andM3 are equal to 1.0 for the materials in the pavement structure. The overall standarddeviation is 0.5, the initial PSI is 4.5, and the TSI is 2.5. The daily traffic has 1080 20-kipsingle axles, 400 24-kip single axles, and 680 40-kip tandem axles. How many yearswould you estimate this pavement would last (how long before its PSI drops below aTSI of 2.5) if you wanted to be 90% confident that your estimate was not too high,and if you wanted to be 99% confident that your estimate was not too high?arrow_forwardA flexible pavement is to be designed to last 10 years. The initial PSI is 4.2 and the TSI (the final PSI) is determined to be 2.5. The subgrade has a soil resilient modulus of 15,000 lb/in². Reliability is 95% with an overall standard deviation of 0.35. For design, the daily car, pickup truck and light van traffic is 40,000 and the daily truck traffic consists of 1500 passes of single-unit trucks with two single axles and 325 passes of tractor semi-trailer trucks with single, tandem, and triple axles. The axle weights are: Cars, pickups, light vans = two 2 kip single axles Single-unit truck = 8 kip single axle and 24 kip single axle Tractor semi-trailer truck = 10 kip single axle, 18 kip tandem axle, and 42 kip triple axle. ● ● M₂ and M3 are equal to 1 for the materials in the pavement structure. Four inches of hot- mix asphalt (HMA) is to be used as the wearing surface and 10 inches of crushed stone as the subbase. Determine the thickness required for the base if soil cement is the…arrow_forward
- A flexible pavement is constructed with 4 inches of hot-mix asphalt (HMA) wearing surface, 8 inches of emulsion/aggregate-bituminous base, and 8 inches of crushed stone subbase. The subgrade has a soil resilient modulus of 10,000 lb/in^2, and M2 and M3 are equal to 1.0 for the materials in the pavement structure. The overall standard deviation is 0.5, the initial PSI is 4.5, and the TSI is 2.5. The daily traffic has 1080 20-kip single axles,400 24-kip single axles, and 680 40-kip tandem axles. How many years would you estimate this pavement would last (how long before its PSI drops below a TSI of 2.5) if you wanted to be 99%confident that your estimate was not too higharrow_forwardSubject: Transportation Engineering An asphalt pavement carries a static wheel load of 125 kN. The circular contact radius of the tire is 180 mm and the transmitted load is distributed across a wide area of subgrade at an angle of 47°. The subgrade bearing value is 0.30 MPa while that of the base is 0.60 MPa. Design the thickness of the pavement and that of the base ? Please give me right solution.. urgenttttttttt help me Thank youarrow_forwardA flexible pavement has a 210 mm hot-mix asphalt “HMA” wearing surface, a 300 mm base (MG-20), and a 500 mm subbase (MG-112). The pavement was designed with 95% reliability, an overall standard deviation So of 0.45, and a APSI of 1.75 (a TSI of 2.5). The drainage coefficient is 0.8 for the base and subbase. The materials properties are as follows: - = Resilient modulus of HMA 2 894 MPa (or 420 000 psi); Resilient modulus of base (MG-20) = 169 MPa (or 24 500 psi); Resilient modulus of subbase (MG-112) = 74 MPa (or 10 700 psi); Effective roadbed soil resilient modulus = 36 MPa (or 5 200 psi). How many 18-kip (80-KN) single-axle loads can be carried before the pavement reaches its TSI (terminal serviceability index).arrow_forward
- Q2) A wheel load with circular area has a radius 6 in. and uniform pressure 552 kPa is applied on a two-layer system, consists of asphalt layer has an elastic modulus of 350000 psi and stabilized subgrade has elastic modulus 70000 psi. The subgrade can support a maximum vertical stress allowing for allowable number of stress repetitions of 2.5 x 109 before occurring of permanent deformation. Calculate the required thickness of a full-depth pavement, deflection in pavement and the critical tensile strain at the bottom of asphalt layer.arrow_forwardXarrow_forwardA flexible pavement is constructed with 4 in. (10.16 cm) of hot mix asphalt wearing surface, 8 in. (20.32 cm) of emulsion/aggregate-bituminous base, and 8 in. (20.32 cm) of crushed stone subbase. The subgrade has a soil resilient modulus of 10,000 psi (68.95 MPa), and M2 and M3 are equal to 1.0 for the materials in the pavement structure. The overall standard deviation is 0.5, the initial PSI is 4.5, and the TSI is 2.5. The daily traffic has 1080 20-kip (89.0-kN) single axles, 400 24-kip (106.8-kN) single axles, and 680 40-kip (177.9-kN) tandem axles. How many years would you estimate this pavement would last (i.e., how long before its PSI drops below a TSI of 2.5) if you wanted to be 99% confident that your estimate was not too high, and if you wanted to be 95% confident that your estimate was not too high?arrow_forward
- Determine the thickness of the flexible pavement for a wheel load of 50KN, if the allowable bearing pressure on the base of the pavement is 0.15MPa and the equivalent radius of the contact area of the tires is equal to 165mm. answer should be in mm.arrow_forward3. Compute the thickness of a flexible pavement for a wheel load of 50 kN, if the allowable bearing pressure on the base of the pavement is 0.15 MPa and the equivalent diameter of the contact area of the tires is equal to 165 mm.arrow_forwardplease help with transportation problem. please make sure it is correct. Will thumbs up if correct.arrow_forward
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