Molds: Rigid, dimensionally stable, nonabsorptive material, warp and buckle free, that will provide continuous and true precast concrete surfaces within fabrication tolerances indicated; non-reactive with concrete and suitable for producing required finishes.
Mold-Release Agent: Commercially produced liquid-release agent that will not bond with, stain or adversely affect precast concrete surfaces and will not impair subsequent surface or joint treatments of precast concrete.
Delete below if form liners are not used. Form liners may be used to achieve a special off-the-form finish or to act as a template for thin or half brick facings. Revise to add description if particular form liner is selected.
Form Liners: Units of face design, texture, arrangement, and configuration [indicated] [to match precast concrete design reference sample]. Provide solid backing and form supports to ensure that form liners remain in place during concrete placement. Use with manufacturer’s recommended liquid-release agent that will not bond with, stain, or adversely affect precast concrete surfaces and will not impair subsequent surface or joint treatments of precast concrete.
Delete below if not using retarder to help obtain exposed aggregate finish.
Surface Retarder: Chemical set retarders capable of temporarily delaying hardening of newly placed concrete mix to depth of reveal specified.
Select only one of the paragraphs and subparagraphs below to suit steel reinforcement requirements. If retaining “Performance Requirements” Article, consider reviewing selections with fabricators.
A.Reinforcing Bars: ASTM A 615/A 615M, Grade 60 (Grade 420), deformed.
Retain paragraph below for reinforcement that is welded or if added ductility is sought.
Low-Alloy-Steel Reinforcing Bars: ASTM A 706/A 706M, deformed.
The presence of chromate film on the surface of the galvanized coating is usually visible as a light yellow tint on the surface. ASTM B 201 describes a test method for determining the presence of chromate coatings. Use galvanizing where corrosive environment or severe exposure conditions justify extra cost.
Galvanized Reinforcing Bars: ASTM A 767/A 767M, Class II zinc coated, hot-dip galvanized and chromate wash treated after fabrication and bending, as follows:
Select type of reinforcement to be galvanized from subparagraph below.