Laserfiche WebLink
B. Ramp grades are critical for access to the raised platform and to meet ADA <br /> requirements. Prior to pouring any concrete for ramp construction, the Contractor shall <br /> check elevations and grades established by formwork. <br /> PLATFORM VERTICAL CURB <br /> 1. Provide monolithic finish to interior curbs by stripping forms while concrete is still green <br /> and by steel-troweling surfaces to a hard, dense finish with corners, intersections, and <br /> terminations slightly rounded. <br /> 2. To allow for ease in concrete pouring and screeding adjacent to the vertical curb, vertical <br /> `L' bars for the vertical curb may be trimmed slightly below the platform slab surface and <br /> the vertical bars drilled and epoxied after the concrete platform has cured. <br /> 3. Chamfer exterior corners and edges of permanently exposed concrete. <br /> 4. Smooth-Formed Finish: As-cast concrete texture imparted by form-facing material, <br /> arranged in an orderly and symmetrical manner with a minimum of seams. Repair and <br /> patch tie holes and defective areas. Completely remove fins and other projections. <br /> PLATFORM JOINTS <br /> 1. Construct joints true to line with faces perpendicular to surface plane of concrete. <br /> 2. Isolation Joints: Install joint-filler strips at junctions with slabs-on-grade and vertical <br /> surfaces, such as column pedestals, foundation walls, and other locations, as indicated. <br /> 3. Extend joint fillers full width and depth of joint, terminating flush with finished concrete <br /> surface, unless otherwise indicated. <br /> 4. Control and Contraction Joints in Slabs-on-Grade: Form weakened-plane control and <br /> contraction joints, sectioning concrete into areas as indicated on Plans by sawcutting. <br /> Construct control and contraction joints with power saws equipped with shatterproof <br /> abrasive or diamond-rimmed blades. Cut joints into concrete when cutting action will not <br /> tear, abrade, or otherwise damage surface and before concrete develops random <br /> contraction cracks. Sawed joints shall be cut same day as concrete pour. <br /> JOINTS AND JOINT SEALANTS <br /> 1. Shop Drawings: Submit single-line diagram showing locations of all joints to be filled and <br /> sealed. <br /> 2. Verify that a minimum of 28 days have elapsed since date concrete was placed, and that <br /> joint surfaces are dry. <br /> 3. Verify also that ambient and concrete-surface temperatures and humidity are within the <br /> ranges recommended by the manufacturer for successful sealant application. <br /> 4. Thoroughly clean joints free of dirt and debris. <br /> 5. Installation/Application Requirements: Joint fillers and sealing compounds shall be <br /> installed in accordance with the respective manufacturers' installation and application <br /> instructions. <br /> 6. Expansion (Isolation) Joints: <br /> a. Provide premolded joint filler to full depth of slabs, less 1/2-inch. Install joint <br /> filler with top edge 1/2-inch below the surface, and tool adjacent concrete <br /> edges to a 3/8-inch radius. Use steel pins to hold material in place during <br /> placing and floating of concrete. Finished joints shall be tight and leak proof. <br /> b. After a minimum of 28 days after slabs have been placed and finished, fill <br /> expansion joints with joint sealing compound to 1/8-inch below surface of <br /> Swift Green Line—Corridor Stations Special Provisions SP146 <br /> May 2017 <br />