Airport pavement design and evaluation

Original publisher: [Washington, D.C.] : U.S. Dept. of Transportation, Federal Aviation Administration, [2004] OCLC Number: (OCoLC)317496721 Subject: Pavements -- United States -- Design and construction. Excerpt: ... 4 / 30 / 2004 AC 150 / 5320-6D Change 3 c. Modulus of Subgrade Reaction. The modulus of subgrade reaction is determined by plate bearing tests performed on the subgrade. These tests should be made in accordance with the procedures established in AASHTO T 222. An important part of the test procedure for determining the subgrade reaction modulus is the correction for soil saturation that is contained in the prescribed standard. The normal application utilizes a correction factor determined by the consolidation testing of samples at in situ and saturated moisture content. For evaluation of older pavement where evidence exists that the subgrade moisture has stabilized or varies through a limited range, the correction for saturation is not necessary. If a field plate bearing test is not practical, the modulus of subgrade reaction may be determined by nondestructive testing or estimated by using Table 2-3 in Chapter 2 of this AC. Fortunately, pavement evaluation is not too sensitive to the modulus of subgrade reaction. ( 1 ) Adjustment for Subbase. An adjustment to the modulus of subgrade reaction will be required if a subbase exists beneath the existing pavement. The thickness of the subbase is required to calculate an adjusted k value. The subbase thickness can be determined from construction records or from borings. The guidance contained in Chapter 3, Section 3, should be used in assigning a k value to a subbase. 605. APPLICATION OF RIGID PAVEMENT EVALUATION PROCEDURES. The evaluation of rigid pavements for aircraft weighing more than 30,000 pounds ( 13 600 kg ) requires concrete flexural strength, k value of the foundation, slab thickness, and annual departure level as inputs. The rigid pavement design curves in Chapter 3 are used to establish loa...