456 ARCHITECTURAL TREATMENT

From SHA MediaWiki
Jump to navigation Jump to search
This is not a legal document. Please see disclaimer for more information.
456.01 DESCRIPTION
Provide architectural treatment on structures such as bridge end post, parapets, abutments, piers, retaining walls, and noise barriers. The type of architectural treatment shall be as specified. Apply form release agents, form stripping methods, patching materials, and construction procedures that are mutually compatible with the surface finish and concrete stain. Architectural treatments not requiring form liners or stain shall conform to all applicable requirements including sample panels.
456.02 MATERIALS
Form Liners       As specified
Form Release Compound       902.08
Concrete Stain       902.18
456.02.01 Form Liner. Match the form liner finish to the textured finish as specified.
The form liner shall attach easily to the forming system, and shall not compress more than 0.021 ft when poured vertically at a rate of 10 ft/hour. Provide liners capable of withstanding anticipated concrete pour pressures without leakage causing physical or visual defects. Provide liners that do not cause concrete surface deterioration or weakness in the substrate when removed.
456.02.02 Form or Wall Ties. When form or wall ties are used that result in a portion of the tie permanently embedded in the concrete, submit the type of form ties for approval prior to use in this work.
456.02.03 Form Release Compound. Provide release agent that is compatible with the surface finish and concrete stain to be applied.
456.02.04 Concrete Stain. Provide the color of the concrete stain for the Color No. specified according to AMS-STD-595A or match an existing structure where specified. Provide a penetrating stain mix coloring agent with compatible color finish designed for exterior application on new or old concrete with field evidence of resistance to moisture, alkali, acid, mildew, mold and fungus discoloration or degradation. Provide breathable coloring agent that allows moisture and vapor transmission. Select the stain from the Qualified Products List (QPL) maintained by the Office of Materials Technology.
456.03 CONSTRUCTION
Furnish and install form liners and provide aesthetic treatment as specified. When form liners are specified, submit actual form liner to be used for tentative approval. Final approval of the form liner will be dependent on how a particular form liner is to be placed throughout the entire structure to achieve the desired aesthetic for the project.
456.03.01 Contractor Uniformity Responsibility. When a project specifies that the same architectural treatment be applied to multiple structures and portions of various structures such as parapets, abutments, piers, retaining walls, and noise barriers that will be in close proximity of each other, ensure that the same architectural treatment or manufacturer’s form liner is used by all subcontractors and that any staining requirements are uniform throughout those structures. The Administration’s form liner approval process ensures that the specific form liner produces a product that conforms to the specified results; it does not relieve the Contractor of the responsibility for uniformity throughout the project. Apply architectural treatments as to not provide a detectable repeating pattern for the length of the element, unless this effect is desired by the Administration.
456.03.02 Inspection of Architectural Treatments. Inspect all elements to be used in the final structure for aesthetic treatment acceptability at the fabrication plant prior to loading on shipping vehicle, when applicable. Inspections shall also be conducted upon delivery of elements at the project site and prior to final acceptance of the structure for maintenance.
456.03.03 Outdoor Lighting Conditions. Make aesthetic treatment inspections for all elements in outdoor lighting conditions. “Outdoor lighting conditions” is defined as during daylight hours in direct sunlight or under artificial lighting providing a minimum illumination of 20 ft candles (20 ft-c) across the entire inspection area. The Contractor or producer shall provide certified test results by a professional lighting expert acceptable to the Administration that any artificial lighting arrangements meet a minimum of 20 ft-c across the entire inspection area. Elements failing to conform to these requirements will be rejected.
456.03.04 Sample Panels. When applicable, sample panels are not to be fabricated until the form liner has been approved by the Administration for use on the project. Prior to fabrication or construction of elements to be used in the final structure, demonstrate workmanship by constructing an approved sample panel for the architectural treatment specified using approved form lining materials, surface coloring, aggregate, and/or absorptive finish. Provide sample panels at the project site for inspection and approval. Use the same formwork including form or wall ties proposed for use and concrete placement for the sample panel as that used for the finished structure.
The form liner used shall produce the same pattern that is intended for use on the finished structure. When the finished structure will contain vertical or horizontal form liner seams/joints, the sample panel shall include the same appropriate seams/joints. Provide sample panel of unreinforced concrete cast in the same position (vertically or horizontally) as will be the finished product to determine the surface texture resulting by use of the form liner. The minimum size of concrete sample panel shall be 6 in. thick, 4 ft wide and 4 ft high.
Remove rejected samples from the project and submit a new sample at no additional cost to the Administration. The approved sample panel shall remain on the site as a basis for comparison to the structure.
456.03.05 Preliminary Sample Panel Digital Photograph Inspection. Provide digital photographs of the small sample panel (4 ft x 4 ft). Supply the photographs by email or CD at the time the Administration is notified of panel delivery to the project site. The photographs will be used in evaluating the acceptance of the finish, but will not replace or supersede the delivery of sample panels as required in the specifications. The Administration reserves the right to make an on-site inspection at any time, or to request additional photographs.
Use a digital camera with a minimum resolution of 6.1 megapixels, and take all photographs without the use of the camera’s zoom features. Take all photographs with the camera’s line of sight being approximately perpendicular on the horizontal to the surface of the sample panel. Heed this requirement throughout this procedure regardless of the orientation of the sunlight. Take multiple photographs with variations in the angle of the sunlight shinning on the sample panel. This may be accomplished by rotating the sample panel so that the sunlight shines from almost directly behind the camera (90 degrees from the sample panel face), to a side lighting view where the sunlight shines on the surface from about 170 degrees from the sample panel face. Take photographs in approximately 15 degree increments, and be free of shadows from the camera and other foreign objects. The camera may be required to be plus or minus perpendicular to accomplish this requirement when the sun is shining on the sample panel at a 90 degree angle.
Submit additional photographs depicting the relief, colors, etc., provided that they conform to these requirements.
Take photographs so that the top and bottom of the sample panel fills the camera’s view screen without the use of the zoom feature. Place a card adjacent to the sample panel in each photograph identifying the Administration’s Contract Number, the supplier, the casting date for each panel; and a 1 in. x 6 in. black bar, a ruler, or other means of showing scale that is legible when viewing the photograph.
Take all photographs in the presence and at the direction of the Administration’s Inspector, and submit electronic copies made directly from the camera’s memory device to them at the time of the inspection (enhancing or modifying the photographs in any way is prohibited). The Inspector will forward the photographs and the information below to the Office of Structures, Office of Highway Development, and the Landscape Programs Division, as appropriate. Provide certification of the photographs at the same time that the photographs are submitted. The certification with the photographs shall contain the following information:
(a) Casting date.
(b) Contract Number.
(c) Description of the sample with file names for each sample.
(d) Number of images sent.
(e) Date and time the images were shot.
(f) Panel serial numbers, or other identifying markings.
(g) A certification that the panel has not been used on a previous project, that the panel is uniquely marked, and that the photographs were taken in their presence.
Failure to produce legible electronic photographs in accordance to these requirements will be cause to delay the evaluation of sample panels/posts, at no additional cost to the Administration or any Contract time extension.
456.03.06 On-site Inspection. Following submittal of acceptable photographs, and at the discretion of the Administration, the Office of Structures, Office of Highway Development or the Landscape Programs Division will conduct an on-site inspection of the sample panels for approval of aesthetic treatment for use on the final structures. The inspection will include the staining and final finish of the sample panels.
456.03.07 Production Requirements. Carefully blend form liner butt joints into the approved pattern and finish off the final concrete surface. There shall be no visible vertical or horizontal seams or conspicuous form marks created by butt joining form liners. The finished texture, pattern, and color shall conform to the approved sample panel, and shall be continuous without visual disruption. The Engineer may reject portion of the structure for failure to comply with these requirements. Remove rejected portions of the structure completely from the project at no additional cost to the Administration.
Prior to each pour, clean the form liners to be free of build up. Visually inspect each liner for blemishes and tears. Make repairs according to the manufacturer’s recommendations and at no change in the appearance of the final product.
Securely attach form liners to forms according to the manufacturer’s recommendations, and with less than a 1/4 in. seam.
Apply the release agent in accordance to the manufacturer’s recommendations so as not to be detrimental to the final structural appearance or the application of stain or other surface treatments.
When the concrete is at least 28 days old, pressure wash surfaces to be stained with a pressure washer set at 3000 psi to remove laitance. Hold the fan nozzle perpendicular to the surface at a distance of 1 ft to 2 ft. Abrasive blasting is prohibited. Provide a completed surface free of blemishes, discolorations, surface voids, and conspicuous form marks as approved. Correct any surface problems at no additional cost to the Administration.
Unless otherwise specified, apply two coats of concrete stain according to the manufacturer’s recommendations and as directed.
When the Contract Documents include expansion joints, finish the joint material so as to visually continue the simulated stone/brick pattern uninterrupted. Include a sample of the colored expansion joint material in the sample panel for approval.
456.03.08 Final Aesthetic Inspection and Approval. Obtain final aesthetic approval when project is complete. Contractor is responsible for structural aesthetic appearance until the project is accepted for maintenance by the Administration.
456.04 MEASUREMENT AND PAYMENT
Architectural Treatment will not be measured but the cost for development and preparation of working drawings, the development and furnishing of all form liners, the construction and finishing of all sample panels, the application of the form liner finish including application of colors, and all material, labor, equipment, tools, and incidentals necessary to complete the work will be incidental to the Contract price for the pertinent Concrete or Structure item.