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M II il11 I I N! u ue I u' I hl I 1!0 521 -3.4 Procurement of Precast Temporary Barrier Wall Meeting the Requirements of Design Standards, Index No. 414: Obtain and use Precast Temporary Barrier Wall from a manufacturing plant that is currently on the Department's list of the qualified Precast Concrete Barrier Wall plants. 521 -3.5 Reflector Elements: Mount reflectors onto the barriers in accordance with the details shown in the plans and the Design Standards. 521 -4 Construction. 521 -4.1 General: The Contractor may use stationary removable forms or slip form construction methods provided a completed barrier wall with acceptable alignment and finish is obtained. Construct forms of metal or timber with a form liner. Do not use forms which are damaged or are not in alignment. At no expense to the Department, remove and replace sections of barrier wall having unconsolidated concrete, surface blemishes, deviations in alignment or profile which exceed tolerances, or other defects which cannot be repaired to the satisfaction of the Engineer. 521 -4.2 Stationary Form Construction: Provide precast or cast in place concrete barrier wall constructed using stationary forms in accordance with Section 400 and providing a Class 3 finish. Align and erect the stationary form so that all plane surfaces of the finished wall will have no deviation greater than 3/8 inch [10 mm] measured as an ordinate between the concrete and a 10 foot [3.048 m] straightedge. Correct all alignment deviations greater than 3/8 inch [10 mm]. Straightedge by half lapping the straightedge for the full length of all plane surfaces. 521 -4.3 Slip Form Construction: When electing to use the slip form method in lieu of the stationary forming method, place the concrete with a slip form machine approved by the Engineer. Provide a finished texture to the slip formed barrier wall by hand troweling, brushing, or both to eliminate pockmarks, blemishes and any other discontinuities in surface texture. Ensure that the final finish has a fine texture and is free of pinholes, pockmarks, and blemishes. Remove and recast or repair sections of slip formed barrier wall having areas of unconsolidated concrete, having surface blemishes, and /or having pockmarks greater than 1/2 inch [13 mm] in diameter after hand troweling and brushing. Repair areas of unsatisfactory surface finish by hand methods using mortar screened from the concrete used to construct the barrier wall. Use the mortar screened from the barrier wall concrete only to fill holes and surface blemishes below the slip formed surface of the concrete. Do not use mortar as a surface overlay coating on the barrier wall concrete. During the finishing operation, while the concrete remains plastic, straightedge all plane surfaces of the slip formed barrier wall with a 10 foot [3.048 m] straightedge. Straightedge by half lapping the straightedge for the full length of the plane surfaces. Correct any deviation found during straightedging, greater than 3/8 inch [10 mm], measured as an ordinate between the concrete surface and the straightedge, in an approved manner at no expense to the Department. Do not use surface overlay coatings of mortar screened from the concrete, or surface overlay coatings pf concrete to correct alignment deviations. 521 -5 Curing. Meet the requirements of Section 400. j March 2007 01000 -116 03- 4122.D�