1999-177 A - Laserfiche WebLink

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E: SECTION 02301 SUBGRADE 1. DESCRIPTION A. The subgrade will be constructed such that after being compacted it will conform to the line, grade, and cross sections as shown on the Drawings. Shoulders shall be stabilized and compacted as specified herein for subgrades. 2. FLORIDA BEARING VALUES A. The subgrade shall have a minimum bearing value of 75 pounds per square inch (psi) as determined by the Florida Bearing Value Test. In an area where the bearing value is less than 75 psi, stabilizing material approved by the Engineer shall be furnished by the Contractor, spread and mixed in accord- ance with Section 160-5.3 "Mixing"of the 1986 Edition of the Florida D.Q.T. Specifications. 3. CONSTRUCTION DETAILS A. The subgrade shall be shaped, graded, and rolled to conform to the lines and grades as shown on the Drawings. Fine grading of the subgrade to its final profile shall be accomplished after the existing ground has been excavated as close as possible to the design elevations. In fill areas, fine grading of the subgrade shall be accomplished after fill is spread and compacted in accord- ance with Section 203 of these Specifications - "Backfill and Compaction". B. All drainage culverts and utility conduits which will be installed under the pavement shall be installed prior to the final shaping and compaction of the subgrade. 4. COMPACTION A. The top of the subgrade in both cuts and fills shall be compacted to a minimum of 98 percent of the maximum dry density to the depth specified on the Plans. The required density shall be maintained until the base course has been constructed. The subgrade shall be compacted with an approved self- propelled steel drum or pneumatic tired roller weighing not less than 8 tons. All hollows and depressions which develop under rolling shall be filled in with suitable material. The process of grading and rolling shall be repeated until no depressions develop. After compaction, the top surface of the fine grade shall be true to line and grade at all locations. If the fine grade becomes rutted or displaced due to any cause whatsoever, the Contractor shall regrade it and recompact it. Ditches, drains, and swates shall be maintained along the completed subgrade section after their construction. B. In no case shall the Contractor proceed to construct the base course on the subgrade until the subgrade has been tested for Florida Bearing Values and compaction, line and grade is checked, and approval given by the Engineer. 5. STABILIZED SHOULDERS A. Stabilized shoulders shall be constructed on cacti side of the paved roadway 02301 1