Local Bridge Fatigue Detail Screening David Conkel Mn

Local Bridge Fatigue Detail Screening David Conkel, Mn. DOT State Aid Bridge Davide Hedeen, Mn. DOT Bridge Barritt Lovelace, Collins Engineers Mn. DOT State Aid | mndot. gov

Project Overview • Evaluate local MN Bridges for fatigue details • Rank and identify steel bridges with likely fatigue details per “Bridge and Structure Inspection Program Manual” • Review plans and bridge information to identify and classify details • Update bridge inventory to include Element 882 Steel Cracking • Future bridge safety inspection will evaluate Element 882 in the field • Closely follows 2007 Mn. DOT Steel Fatigue Research Report Local Road Research Board Project 9/10/2021 Mn. DOT State Aid | mndot. gov 2

Goals and Deliverables Ensure evaluation of steel fatigue details on local bridge system Updated local bridge inventory to include Element 882 Steel Cracking 9/10/2021 Mn. DOT State Aid | mndot. gov 3

Fatigue • Fatigue is damage to steel by cyclical loading • Can occur even below design stresses • Greatly affected by design details and fabrication defects • 18 fatigue prone details for steel bridges 9/10/2021 Mn. DOT State Aid | mndot. gov 4

Fatigue Details 9/10/2021 Mn. DOT State Aid | mndot. gov 5

Fatigue Details Example – Transverse Web Stiffener 9/10/2021 Mn. DOT State Aid | mndot. gov 6

Steel Fatigue Evaluation 9/10/2021 Mn. DOT State Aid | mndot. gov/ 7

Results 9/10/2021 Mn. DOT State Aid | mndot. gov/ 8

Results 9/10/2021 Mn. DOT State Aid | mndot. gov/ 9

Results 9/10/2021 Mn. DOT State Aid | mndot. gov/ 10

Conclusion 9/10/2021 Mn. DOT State Aid | mndot. gov/ 11

Questions? 9/10/2021 Mn. DOT State Aid | mndot. gov 12