NBIS Bridge Inspections (NBIS: National Bridge Inspection System)
Reinspection of 972 bridges in South Eastern counties of Pennsylvania, on the East coast of the USA. Project consisted of hands-on inspection for structural defects, safety features, functional capacity and waterway adequacy. Reports included findings, conclusions, recommendations, photographs and SI&A (BMS) coding forms, Bridges varied in length from 20 feet to over 500 feet with 528 major bridges of over 100 feet in length including 18 bridges over 330 feet in length. Bridge types included trusses, steel, masonry and concrete, and pre-stressed concrete. Scour susceptibility of al bridges crossing waterways was an important factor.
Monthly visual and ultrasonic hanger-pin assembly and fatigue cracking inspections were performed for three structures of over 100 feet until they could be retrofitted: routes 422, 291 and I-95 bridges over the Schuylkill River. Hands-on inspection, measurements, and field notes were performed on a monthly basis. The detailed reports contained findings and graphics, as well as actual-theoretical steel expansion comparison charts.
Brief Description of Services Provided
- Data collection
- Condition survey with in-depth inspection
- Identification and preparation of detailed sketches for serious deficiencies
- Evaluation of fracture critical members
- Re-evaluation of weight posting (rate analysis)
- Underwater inspection
- Maintenance recommendations
- Preparation of comprehensive inspection report.