A Personal Recollection by Roger A.Dorton - ogra Roger Dorton_Innovation in Bridge... · Twinning...
Transcript of A Personal Recollection by Roger A.Dorton - ogra Roger Dorton_Innovation in Bridge... · Twinning...
A Personal Recollection
by
Roger A.Dorton
Expo ‘67 Bridge Design Competition, 1967
A. Murray MacKay Suspension Bridge , 1970
Lions’ Gate Bridge Renovation, 1976
Conestogo River Test Bridge , 1976
Ontario Highway Bridge Design Code, 1979
Twinning the Burlington Skyway, 1985
Confederation Bridge, N.B. to P.E.I., 1997
Twinning the Blue Water Bridge, 1997
Angus L. Macdonald
Bridge, 1956, by
P.L. Pratley.
Through Truss Design
Suspended Deck
Details, MacKay
Bridge
Cross Section of Deck, B-B
Full Aeroelastic Model, Tested by Alan Davenport
Suspended Span
Weights for Medium
Span Bridges
A. Murray MacKay Bridge the lightest suspension bridge with spans over 1,000 feet in 1970.
Modification to the North Cable Bent, 1976
Replacement of the Suspended Structure, 2002
Lions’ Gate Bridge
Renovation, 1976,
2002
North Cable Bent
Cable Slippage
Deformed Shape
from 125mm Cable
Slippage and
Footing Rotation
Sequence of
Operations
For rotation of the north cable bent footings
1979,1983,1991
1. Limit States Design Replaced Working Stress
2. Load Factors Calibrated to 3.5 Safety Index
3. Deck Slab Arching Action, Only 0.3% Steel
4. Allowed Increase in Legal Truck Loads
5. New Dynamic Load Allowance
6. Full Commentary for the Code
7. Paid Consultants
8. Not a Consensus Code
9. Full MTO Management Support
Load and Resistance Factors Calibrated to a Safety Index of 4.0