OPAC Consulting Engineers

Ping Ding Steel Arch Bridge

Suburban Taipei, Taiwan


Join Engineering Consultants, Taipei


Design completed 1993
Construction completed 1994

Scope of work:

Value Engineering and Design

Construction cost:

US$ 3,000,000

Services Performed:

  • Bridge type selection
  • Preliminary design
  • Final design
  • Construction support


  • Value Engineering
  • Steel arch design
  • Seismic design

The Ping Ding Steel Arch Bridge provides access to a private housing development and community center in the suburbs of Taipei, Taiwan. It carries two lanes of vehicular traffic and sidewalks. It was designed by OPAC to provide an economical, aesthetic, and rapidly built bridge to provide construction- and permanent- access across a deep ravine.

The 120 meter long bridge consists of a 60 meter span arch with twin steel box ribs, supporting open spandrel bents with steel bent caps. The composite deck consists of steel girders and a cast-in-place concrete slab, with expansion joints at the extreme ends only. Geotechnical conditions allowed use of spread footings in the ravine walls to resist the arch thrust. The steel was fabricated locally, with shop-welded and field-bolted splices.

OPAC was engaged by the design engineer for the project developer, to resolve cost and construction schedule issues of an earlier segmental concrete bridge design using a Value Engineering approach. OPAC was later engaged to design the bridge. A concrete arch with cast-in-place ribs and precast deck was also designed. The steel design was chosen for construction based on cost and construction schedule advantages.