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STORMWATER REPAIRS TO WHITTED BUILDING <br /> HILLSBOROUGH,NC 03/26/13 <br /> 3.4 EXCAVATION, GENERAL <br /> A. Unclassified Excavation: Excavate to subgrade elevations regardless of the character of surface <br /> and subsurface conditions encountered. Unclassified excavated materials may include rock, soil <br /> materials, and obstructions. No changes in the Contract Sum or the Contract Time will be <br /> authorized for rock excavation or removal of obstructions. <br /> 3.5 EXCAVATION FOR STRUCTURES <br /> A. Excavate to indicated elevations and dimensions within a tolerance of plus or minus 1 inch (25 <br /> mm). If applicable, extend excavations a sufficient distance from structures for placing and <br /> removing concrete formwork, for installing services and other construction, and for inspections. <br /> 1. Excavations for Footings and Foundations: Do not disturb bottom of excavation. <br /> Excavate by hand to final grade just before placing concrete reinforcement. Trim <br /> bottoms to required lines and grades to leave solid base to receive other work. <br /> 3.6 EXCAVATION FOR WALKS AND PAVEMENTS <br /> A. Excavate surfaces under walks and pavements to indicated lines, cross sections, elevations, and <br /> subgrades. <br /> 3.7 SUBGRADE INSPECTION <br /> A. Notify Architect when excavations have reached required subgrade. <br /> B. If Architect determines that unsatisfactory soil is present, continue excavation and replace with <br /> compacted backfill or fill material as directed. <br /> C. Proof-roll subgrade below the building slabs and pavements with heavy pneumatic-tired <br /> equipment to identify soft pockets and areas of excess yielding. Do not proof-roll wet or <br /> saturated subgrades. <br /> 1. Completely proof-roll subgrade in one direction,repeating proof-rolling in direction <br /> perpendicular to first direction. Limit vehicle speed to 3 mph(5 km/h). <br /> 2. Proof-roll with a loaded 10-wheel, tandem-axle dump truck weighing not less than 15 <br /> tons(13.6 tonnes). <br /> 3. Excavate soft spots, unsatisfactory soils, and areas of excessive pumping or rutting, as <br /> determined by Architect,and replace with compacted backfill or fill as directed. <br /> D. Reconstruct subgrades damaged by rain, accumulated water, or construction activities, as <br /> directed by Architect,without additional compensation. <br /> 3.8 UNAUTHORIZED EXCAVATION <br /> A. Fill unauthorized excavation under foundations or wall footings by extending bottom elevation t <br /> of concrete foundation or footing to excavation bottom, without altering top elevation. Lean <br /> EARTHWORK 02300-4 <br />