Tiêu chuẩn quốc tế

• Số hiệu / Standard Number: AASHTO PP 55:2006
• Năm ban hành / Publication date: 2006
• Tình trạng / Status: W - Hết hiệu lực
• Tên tiếng Anh / Title in English: Standard Practice for Overcoating Field Test Program for Evaluating Protective Coatings on Existing Bridges or Salvaged Beams
• Thay thế cho / Replace: AASHTO PP 55:2003
• Số trang / Page: 10

Phạm vi áp dụng / Scope of standard

This field testing program has been established to provide the
end user with test results that can be used to make performance
judgments on one-, two-, or three-coat systems for maintenance
overcoating previously painted steel structures.

This field testing program is intended to apply to maintenance
overcoating, herein defined as the practice of cleaning and
painting over an existing coating that is largely intact but has
areas of corrosion or peeling paint in need of repair. This
practice usually includes the spot preparation of rusted or
degraded areas, feathering edges of existing paint, power washing
the entire structure, priming bare or repaired areas, applying an
intermediate coat over the repaired areas or entire structure, and
the optional step of applying a full topcoat over the entire
structure, or a similar variation of these procedures.

This field testing program evaluates the performance of
protective coatings applied to existing painted steel surfaces with
various degrees of surface preparation and condition, including
surfaces hand tool cleaned (SSPC SP 2), surfaces cleaned by
conventional power tools (SSPC SP 3), surfaces power tool cleaned
to bare metal (SSPC SP 15), and industrial blast (SSPC SP 14).

The coating materials in the field testing program are applied
to previously painted steel surfaces of existing bridges or
salvaged bridge beams after proper surface preparations, as
described herein, and thereafter evaluated annually, unless
otherwise agreed, for a period of 3 years.

All of the elements of this field testing program shall be
performed in accordance with applicable local, state, and national
regulations governing environmental and worker protection. Specific
references to material, environmental, and worker protection
requirements are not necessarily made in this document since these
regulations are widely known and compliance with these regulations
is standard practice in the bridge painting industry.

This standard may involve hazardous materials, operations,
and equipment. This standard does not purport to address all of the
safety concerns associated with its use. It is the responsibility
of the user of this procedure to establish appropriate safety and
health practices and determine the applicability of regulatory
limitations prior to use.