Ontario Writes New Bridge Code

In 1976, Ontario’s Ministry of Transportation and Communications decided to write its own bridge design code, breaking away from the AASHTO code, because:

1. It wanted a metric design code in 1978, target date for conversion of Canada’s construction industry to the metric system;
2. it considered the AASHTO code too conservative; and
3. it wanted to synthesize its separate research reports into an acceptable design code. In 1973 the Ministry had built a full-scale test bridge designed using its research. Load testing supported the design concepts but the Ministry wanted to test existing bridges, too. Using its research, the Ministry tested a bridge whose replacement had been recommended. As a result, the Ministry was able to repair and strengthen, rather than replace, the bridge. Article describes Ontario’s research and bridge testing and summarizes the new bridge code.