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The minimum thickness of the construction working platform layer shall be as shown <br />below, and shall be thicker if necessary to achieve the minimum specified compaction <br />and maximum deflection requirements. <br />if a treated subgrade, an ICTB or CTB is proposed, a full pavement design shall be <br />performed which also includes a mix design for the treated subgrade, ICTB or CTB to <br />establish the thickness of treatment, the percent cement, the optimum water <br />content, and the maximum density of the treated subgrade, ICTB or CTB. The <br />minimum thickness of the working platform shall be as follows: 12 inches for <br />aggregate sub base or base; 10 inches for an ICTB or CTB; and 12 inches for treated <br />subgrade. The purpose of treatment of the subgrade will be to make the material <br />compactable, so there is no minimum strength requirement, however, the maximum <br />strength shall not exceed 500 psi. The 7 day design strength for ICTB and CTB shall be <br />between 300 psi and 500 psi. Construction of the treated subgrade, ICTB or CTB shall <br />comply with special specifications to be supplied by the City. <br />Asphalt Concrete Mix Formulas <br />Select the level of AC mix to be specified for construction based on the design ESAL's <br />for the life of the pavement. If design ESAL's for the street to be paved exceed 10 <br />million, the mix design and criteria for the mix shall be prepared by a licensed <br />Professional Engineer with specific experience in pavement design. <br />ESAL's <br />Mix Criteria <br />< 10,000 <br />Level 1 <br />10,000 to 1 million <br />Level 2 <br />>1 million, <10 million <br />Level 3 <br />2. Portland Cement Concrete (PCC) <br />PCC pavement structures shall be designed using either the 1998 Supplement to the <br />1993 AASHTO Guide for Design of Pavement Structures (1993 AASHTO Guide) or <br />Portland Cement Association (PCA) approved design specifications. Use the <br />parameters from the 1998 Supplement design method listed in the following table <br />with notes on their suggested values and/or documentation of where the values come <br />from or can be obtained. Design traffic loading shall be calculated as shown above in <br />the AC subsection. <br />Design Parameters for 1998 Rigid Pavement Supplement to AASHTO Guide <br />Public Improvement Design Standards Manual, 2016 1Page 2-34 <br />