425 LIGHTWEIGHT SUPERSTRUCTURE CONCRETE
From MDOT Policy Manual
- Furnish and install lightweight concrete.
Lightweight Concrete 902.10, Mix 10
- Conform to 420.03 and as specified herein.
- Handle lightweight aggregates in a manner that provides a thorough sprinkling of the aggregates during the stockpiling to produce damp aggregate. Sprinkle to obtain uniform distribution of moisture. Then permit the aggregates to drain as long as necessary to produce a uniform moisture content. Maintain the moisture content as much as practical until the aggregate is used. Add the admixtures to the mix according to the manufacturer’s recommendations.
- 425.03.01 Existing StructuresBridges, culverts, catch basins, drop inlets, retaining walls, cribbing, manholes, end walls, buildings, sewers, service pipes, underdrains, foundation drains, steps, fences, and other features that may be encountered in the work and not otherwise classified.. Remove existing bridge decks according to 405.03.02. Note that the deck replacement material may be lighter than the existing deck and the deflection caused by the lighter material will be less than the material removed. Therefore, compute modified rebound figures to be used in lieu of dead load deflections to establish grade controls to produce finished tops of concrete bridge decks that will be true to as planned line and grade.
425.04 MEASUREMENT AND PAYMENT.
- Lightweight concrete structures will be measured and paid for as specified. The payment will be full compensation for all forms and form removal, reinforcing steel, curing and misting, scuppers, mechanical and electrical work, all cost incidental to the conducting of tests for oxygen content and presence of gases and applying mechanical ventilation to confined spaces, year built markings, and for all material, labor, equipment (including safety equipment), tools, and incidentals necessary to complete the work.
- The construction of drainage and weep holes, any pipe necessary, expansion material, flashing, dampproofing, membrane waterproofing, epoxy bonding compound, joints and their placement will not be measured but the cost will be incidental to the lightweight concrete item. No deduction in lightweight concrete quantities will be made for pipes or conduits having diameters less than 8 in., reinforcing steel, anchors, or any other appurtenances.
- 425.04.01 Lightweight SuperstructureAll of that part of the structure above bottoms of bearings of simple and continuous spans, skewbacks of arches and tops of footings of rigid frames, except as noted above for substructure. Concrete will not be measured but will be paid for at the Contract lump sum price unless otherwise specified.
- 425.04.02 Lightweight concrete parapets and median barriers will not be measured but will be paid for at the Contract lump sum price for the pertinent Lightweight Concrete Parapet or Lightweight Concrete MedianThe portion of a divided highway separating the traveled ways for traffic in opposite directions. Barrier items.
- 425.04.03 Floodlighting will be measured and paid for as specified in 420.04.06.
- 425.04.04 Linseed Oil Protective Coating will be measured and paid for as specified in 420.04.07.