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A platform for research: civil engineering, architecture and urbanism
Load Testing for Bridge Rating: Route 22 Over Swamp River
This report discusses instrumentation, load testing, and load rating of Route 22 over Swamp River (BIN 1016720) in Dutchess County (Region 8 of New York State Department of Transportation). The bridge is about 72-ft long, 28-ft wide, and has a 30-degree skew. It was built in 1938 as a single span multi-girder steel structure with a non-composite concrete deck. In 1981, the original deck was replaced with a new concrete deck and the bridge was widened by increasing the length of the fascia overhangs to about 3 ft-4 in. To meet the structural stiffness demand, the overhang depth was increased from 8.5 to13 in. The widening and stiffening of the overhangs increased the dead load on the fascia beams and reduced their load ratings. This also reduced the bridge load rating, which was controlled by the fascia beams load ratings. Level 1 load rating analysis, ignoring composite action between the deck concrete and the bridge beams, was performed by the Region's load rating engineers. Based on this analysis, the bridge inventory and operating ratings, respectively, were estimated at 17 and 36 ton for an AASHTO HS-20 truck, and 13 and 29 ton for an AASHTO H-20 truck. The need to improve the current rating was motivated by the bridge's importance being in a very busy route frequented by heavy truck traffic. The original bridge plans indicated the North abutment as 'fixed' and the South abutment as 'expansion.' The bridge structure was instrumented with strain gages and load tested using 4, 2-axle trucks of known weights and configurations. The testing revealed that the bridge members were much stronger in flexure than what was predicted using the Level 1 load rating analysis. The test results revealed that the bridge had considerable fixity at both abutment ends and that the girders were acting compositely with the concrete deck. Additionally, investigation of transverse load distribution of live load to the bridge girders indicated that the actual load distribution factor is lower than that based on the AASHTO specifications. Utilizing this information, a new working stress rating analysis was performed, and recommendations for the bridge rating at the inventory and operating levels are made in the report.
Load Testing for Bridge Rating: Route 22 Over Swamp River
This report discusses instrumentation, load testing, and load rating of Route 22 over Swamp River (BIN 1016720) in Dutchess County (Region 8 of New York State Department of Transportation). The bridge is about 72-ft long, 28-ft wide, and has a 30-degree skew. It was built in 1938 as a single span multi-girder steel structure with a non-composite concrete deck. In 1981, the original deck was replaced with a new concrete deck and the bridge was widened by increasing the length of the fascia overhangs to about 3 ft-4 in. To meet the structural stiffness demand, the overhang depth was increased from 8.5 to13 in. The widening and stiffening of the overhangs increased the dead load on the fascia beams and reduced their load ratings. This also reduced the bridge load rating, which was controlled by the fascia beams load ratings. Level 1 load rating analysis, ignoring composite action between the deck concrete and the bridge beams, was performed by the Region's load rating engineers. Based on this analysis, the bridge inventory and operating ratings, respectively, were estimated at 17 and 36 ton for an AASHTO HS-20 truck, and 13 and 29 ton for an AASHTO H-20 truck. The need to improve the current rating was motivated by the bridge's importance being in a very busy route frequented by heavy truck traffic. The original bridge plans indicated the North abutment as 'fixed' and the South abutment as 'expansion.' The bridge structure was instrumented with strain gages and load tested using 4, 2-axle trucks of known weights and configurations. The testing revealed that the bridge members were much stronger in flexure than what was predicted using the Level 1 load rating analysis. The test results revealed that the bridge had considerable fixity at both abutment ends and that the girders were acting compositely with the concrete deck. Additionally, investigation of transverse load distribution of live load to the bridge girders indicated that the actual load distribution factor is lower than that based on the AASHTO specifications. Utilizing this information, a new working stress rating analysis was performed, and recommendations for the bridge rating at the inventory and operating levels are made in the report.
Load Testing for Bridge Rating: Route 22 Over Swamp River
O. Hag-Elsafi (author) / J. Kunin (author)
2006
70 pages
Report
No indication
English
Diagnostic Load Testing for Bridge Load Rating
| British Library Conference Proceedings | 1997
Diagnostic Load Testing for Bridge Load Rating
| British Library Online Contents | 1997