Specification:Removing and replacing deteriorated concrete paving

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=GENERAL=

SUMMARY
 This procedure includes guidance on replacing damaged sections of concrete paving. See Specification:General project guidelines for general project guidelines to be reviewed along with this procedure. These guidelines cover the following sections:  Safety Precautions Historic Structures Precautions Submittals Quality Assurance Delivery, Storage and Handling Project/Site Conditions</li> Sequencing and Scheduling</li> General Protection (Surface and Surrounding)</li> </ol> </li> </ol>

PROJECT/SITE CONDITIONS
<ol type="A"> Environmental Requirements: Maintain a constant temperature of 45 degrees F. or above for at least 48 hours prior to placing concrete.</li> </ol> =PRODUCTS=

MATERIALS
<ol type="A"> Portland cement</li> Aggregate</li> Clean, potable water</li> Polyethylene moisture barrier</li> Moisture-retaining cover such as waterproof paper, polyethylene film or polyethylene-coated burlap</li> Expansion joint material such as cork strips</li> </ol>

EQUIPMENT
<ol type="A"> Spade</li> Mechanical vibrating equipment</li> Stiff bristle brushes</li> Straight edge</li> Bull float or darby</li> </ol> =EXECUTION=

ERECTION, INSTALLATION, APPLICATION
<ol type="A"> Remove deteriorated sections of paving to edge of sound pavers and down to structural slab.</li> Remove dirt and debris from surface to receive new concrete.</li> <li>Cut and fit polyethylene moisture barrier to cover the area to receive new concrete.</li> <li>Position expansion joint material at edges of floor slab as required.</li> <li>Lay concrete in layers. DO NOT allow the concrete to harden before placing the next layer. <ol> <li>Consolidate concrete while laying by hand spading, rodding or tamping along with using mechanical vibrating equipment.</li> <li>Work concrete thoroughly into corners.</li> </ol> </li> <li>Fill area flush with adjacent sound concrete and level with a straight edge.</li> <li>Smooth the surface with a bull float or darby to eliminate humps or hollows.</li> <li>Finish surface to match adjacent paving.</li> </ol>

ADJUSTING/CLEANING
<ol type="A"> <li>Protect newly placed concrete from excessive hot and cold temperatures. Cover with moisture-retaining cover while curing. Lap ends at least 3 inches and seal with waterproof tape or adhesive.</li> <li>Allow to cure for a minimum of 7 days.</li> </ol>