ADAPT-ABI: Design and analysis software for conventionally reinforced, post-tensioned, segmental, cable-stayed, balanced cantilever, precast-prestressed and concrete box girder, and spliced-girder bridges.
http://www.adaptsoft.com/specs-abi.shtml

BridgeLCC: Life-cycle costing software for preliminary bridge design. http://www.bfrl.nist.gov/bridgelcc/welcome.html

bulbt: Precast, prestressed bulb-tee design program and source code.
http://www.dot.state.ak.us/external/state_wide/dnc/eos.d/bridge/bridge.html

CONSPAN, CONSPLICE PT, RC-PIER, CONBOX PT and more: Simple and continuous precast/prestressed, spliced-girder, and cast-in-place post-tensioned concrete box girder bridge superstructures and reinforced concrete bridge substructure analysis and design programs, according to both AASHTO Standard and LRFD Specifications.
http://www.leapsoft.com/

Excel Spreadsheets: Spreadsheets that can be used to calculate the shear strengths of beams and columns according to the AASHTO LRFD Specifications.
http://www.ecf.utoronto.ca/~bentz/aashto99.htm

pcaColumn: pcaColumn is a computer program for the design and investigation of reinforced concrete column sections. The column section can be rectangular, round or irregular shaped with any reinforcement layout or pattern, and slenderness effects can be considered.
http://www.pcastructurepoint.com/soft/soft_profile.asp?l_family_id=21

PGSuper and QconBridge: Prestressed Girder superstructure design and analysis software. HL93 Live Load Analysis for continuous bridge structures.
http://www.wsdot.wa.gov/eesc/bridge/Software/

PSBeam is a high-performance, Windows-based system for prestressed concrete bridge girder design. Its 32-bit computational engine processes design changes at blazing speeds, giving you more time to check alternative options and refine your designs.
http://www.eriktech.com/

Response-2000: A program for sectional analysis of beams and columns based on the modified compression field theory.
http://www.ecf.utoronto.ca/~bentz/r2k.htm