TRIS Online Record

Printable View

Title	HIGHWAY ACCIDENT REPORT--COLLAPSE OF NEW YORK THRUWAY (I-90) BRIDGE OVER THE SCHOHARIE CREEK, NEAR AMSTERDAM, NEW YORK, APRIL 5, 1987
Accession No	00469497
Corp. Authors / Publisher	National Transportation Safety Board
Publication Date	19880429
Description	168 p.; Appendices(8); Figures(38); Tables(7)
Abstract	This accident investigation delves into the causes of the collapse of a 5-span, 540-foot-long highway bridge over the Schoharie Creek in Montgomery County near Amsterdam, New York, on April 5, 1987. The report discusses the design and construction of the bridge, the intensity of previous floods, the vulnerability of the soil to scour and the bridge's dependency on riprap protection, and the suitability of spread footings in streambeds subject to high velocity flows. The report also discusses the maintenance and inspection history of the bridge. The report discusses deficiencies uncovered in the bridge inspection programs of the New York State Thruway Authority (owner of the bridge) and the New York State Department of Transportation, and the oversight of their programs by the Federal Highway Administration. The National Transportation Safety Board determines that the probable cause of the collapse of the Schoharie Creek Bridge was the failure of the New York State Thruway Authority to maintain adequate riprap around the bridge piers, which led to severe erosion in the soil beneath the spread footings. Contributing to the accident were ambiguous plans and specifications used for construction of the bridge, an inadequate NYSTA bridge inspection program, and inadequate oversight by the New York State Department of Transportation and the Federal Highway Administration. Contributing to the severity of the accident was the lack of structural redundancy in the bridge. Recommendations are proposed to revise existing guidelines for design, maintenance, and inspection of bridges. In addition, it is recommended that the U.S. Department of Transportation Inspector General periodically review the FHWA bridge inspection audit program for compliance with the National Bridge Inspection Standards.
TRT Terms	Accident causes ; Accident investigation ; Accident reports ; Accident severity ; Bridge design ; Bridges ; Collapse ; Construction ; Erosion ; Floods ; Flow ; Highway bridges ; Inspection ; Maintenance ; Recommendations ; Redundancy ; Riprap ; Scour ; Specifications ; Spread footings ; Streams ; Structural design ; Velocity
Other Terms	Bridge inspection; Bridge maintenance; Construction specifications; Scouring; Stream flow velocity; Structural redundancy
Subject Areas	H51 SAFETY; H25 STRUCTURES DESIGN AND PERFORMANCE; I82 Accidents and Transport Infrastructure; I24 Design of Bridges and Retaining Walls
Report Number	NTSB/HAR-88/02; 4656A
Availability	National Technical Information Service Order Number: PB88-916202
TRIS Files	HRIS
Database	TRIS Online