#Aashto 1993 pavement design guide pdf pdf
AASHTO Roadside Design Guide 4th Ed 2011 PDF | Land.David Bleazard, CEO of First Service Credit Union, expressed reduction that no person else used to be harm in the incident. (C.6) for the required slab thickness: D = 10.55 ≈ 10.5 inches.Robbery suspect fatally shot at credit union in BrookshireYour browser indicates when you've visited this hyperlink Determine the other input parameters: joint load transfer coefficient J = 3.2, drainage coefficient C d = 1.0.Specify the PCC properties: S c = 690 psi, E c = 4.4 × 10 6 psi (these would typically be from material specifications mean values should be used for inputs).Specific design inputs to this procedure are the seasonally averaged subgrade resilient modulus M R = 7,500 psi, the assumed thickness of the granular subbase D SB, the seasonally averaged subbase resilient modulus E SB = 40,000 psi, the depth to bedrock D SG (if less than 10 feet-not the case for this example design), and the loss of service coefficient LS = 2. Evaluate the effective modulus of subgrade reaction k using the procedures described in Section 5.4.6.Determine the terminal serviceability and allowable serviceability loss due to traffic: p t = 2.5, ΔPSI = 1.9 (this may be reduced if frost heave or swelling soils are an issue).Evaluate the design traffic: W 18 = 18.9 million ESALs.The steps in the 1993 AASHTO rigid pavement design procedure are summarized below in the context of the example baseline scenario presented in Section 6.2.1: Recommended load transfer coefficients for various pavement types and design conditions (AASHTO, 1993). See Section 5.5.1 for determination of the drainage coefficient C d. The joint load transfer coefficient J is a function of the shoulder type and the load transfer condition between the pavement slab and shoulders recommended values are summarized in Table C-4. The PCC parameters S c and E c are standard material properties mean values should be used for the pavement design inputs. Other layer properties include the modulus of rupture S c and elastic modulus E c for the Portland cement concrete slabs, an empirical joint load transfer coefficient J, and the subbase drainage coefficient C d. 1Ĭ.3 Rigid Pavement Structural Design Design Equation Convert SN 2 to the required thickness of granular base: D 2 = SN 2 / m 2 a 2 = 14.3 → 14 inches.Assign the remaining required structural number to the granular base layer:.Convert SN 1 to the required thickness of asphalt: D 1 = SN 1 / a 1 = 5.95 → 6 inches 1.5.16), solve for the required structural number for the asphalt concrete surface layer: SN 1 = 2.62. (C.2) with M R set equal to the granular base resilient modulus E BS = 40,000 psi (from the correlation in Eq. Determine the design layer thicknesses for the pavement section:.(C.2) for the required overall structural number: SN = 5.07. Drainage coefficients m i for all unbound layers (Section 5.5.1): m 2 = 1.0.Recommendations for appropriate a i values for rehabilitation design are given in Table 5-44 in Section 5.4.5.
Structural layer coefficients a i for all bound layers (see Section 0 for asphalt concrete, 1993 AASHTO Guide for other stabilized materials) and unbound layers (Section 5.4.5).Evaluate the seasonally averaged subgrade resilient modulus M R using the procedures described in Section 5.4.3: M R = 7,500 psi.Determine the allowable serviceability loss due to traffic: ΔPSI = 1.7 (this may be reduced if frost heave or swelling soils are an issue).Determine the design reliability factors: Reliability = 90% (usually set by agency policy), Z R = -1.282, S 0 = 0.45.Evaluate the design traffic: W 18 = 11.6 million ESALs.For the example design scenario, a 30-year design life is specified. The steps in the 1993 AASHTO flexible pavement design procedure are summarized below in the context of the example baseline scenario presented in Section 6.2.1: Guidelines for length of analysis period (AASHTO, 1993). AASHTO recommendations for analysis periods for different types of roads are summarized in Table C-1. Analysis period in this context is synonymous with design life in the 1993 AASHTO Guide. However, realistic performance limitations may require planned rehabilitation within the desired analysis period, in which case, the analysis period may encompass multiple performance periods. It may be identical to the performance period. The term 'analysis period' refers to the overall duration that the design strategy must cover. It is equivalent to the time elapsed as a new, reconstructed, or rehabilitated pavement structure deteriorates from its initial serviceability to its terminal serviceability. Performance period refers to the time that a pavement design is intended to last before it needs rehabilitation.
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