Which truck was my concrete bridge designed to carry (in Queensland, Australia)?  By Chris Dowding, Director - Structures Group TOD Consulting, March 2017 Update Revision B, April 15 2017 I ntroduction  Sometimes, the old drawings for a concrete bridge cannot be found. Sometimes, the specific drawing sheet or specification, indicating the design load, has gone missing. How can you estimate what the original load capacity of the bridge was? One way is by first  work out an approximate age of the bridge : Often bridges have a date plate fixed to one Abutment, indicating the year of construction. Bridges built by Queensland's TMR (the State Road Authority) should usually have a date plate. Have a look on site. If you have any of the drawings, there should be dates at the bottom indicating when it was designed and/or when the drawings were issued for construction The year of design and the year of construction are usually different. Often these ac