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1 PDH · about 60 minutes · Course no. BR-L06 · Instructor: Michael Craig, PE
Michael Craig, PE is Senior Vice President and Southeast Director at Strinteg Corporation, leading bridge inspection and structural engineering across eight states and Puerto Rico. In 27+ years he has inspected over 4,000 structures and completed 3,000+ load ratings and 160+ load tests. He has managed repair and preservation design for complex bridges, including cable-stayed bridges. He holds PE licenses in twelve states, DC and Puerto Rico, SPRAT Level 1, and FAA Part 107 credentials.
When an analytical load rating says a bridge must be posted, but the bridge has carried heavy traffic for decades without distress, a field load test can show how the structure actually behaves. This course covers the two kinds of nondestructive load tests in Section 8 of the AASHTO Manual for Bridge Evaluation (MBE): diagnostic tests, which compare measured response with analysis and adjust the calculated rating, and proof tests, which load the bridge to a target level to confirm a lower-bound capacity. It explains the background in NCHRP Research Results Digest 234 (1998), how to plan instrumentation and loading, the MBE equations for the adjustment factor K and for the proof-test operating rating, and the safety and stop criteria that keep a test from damaging the bridge. Equations are as summarized in published DOT research reports and peer-reviewed papers that quote the MBE. Example numbers are illustrative teaching values unless a source is named. Article numbers vary by MBE edition; check the edition your agency has adopted.