Search results for " Gerber saddle"
showing 3 items of 3 documents
Degraded Gerber Saddles in RC Bridges
2023
Sudden failure of reinforced concrete (RC) or prestressed concrete (PC) Gerber saddles of bridges and viaducts has occurred all around in the word in the last few years due to corrosion of steel bars. The danger of sudden and brittle failure is often due to general and pitting corrosion of steel bars, concrete crushing, and loss of bond in steel bars. In this paper, the flexural response of reinforced concrete Gerber supports under their self-weight with or without service loads was investigated through determination of the load-deflection response of beams, with the focus on the consequences of pitting corrosion and loss of bond in steel bars. A simplified strut-and-tie model was developed…
Performance of a historical cantilever reinforced concrete bridge with half-joint degradation
2022
The lack of maintenance of roadway concrete bridges built from the Second World War until the 70 s of the 20th century has led in recent years to an ever-increasing request for safety assessments. When bridge performance in terms of Serviceability Limit State (SLS) and Ultimate Limit State (ULS) has to be evaluated, in-situ visual inspections and load tests for safety and maintenance assessment have to be coupled with structural analysis. In order to identify a sound bridge structural model and to assess the actual conservation state, more refined models than those usually considered for section and reinforcement design should be used to reproduce the results of load tests and perform globa…
Applicazione delle Linee guida italiane alle valutazioni di sicurezza strutturale del ponte Corleone sulla tangenziale di Palermo
2022
The "nominal life" of a large part of existing reinforced and prestressed concrete bridges, in Italy, is expiring, often in the absence of ordinary or extraordinary maintenance. Consequently, the Italian infrastructural network is in a critical phase, followed by the alarmed awareness of the public opinion, especially after the collapse of the Polcevera viaduct. Specific guidelines on risk classifi-cation, management, safety assessment, monitoring of existing bridges have been issued by the Superior Council of Public Works in 2020, to address the emergency. Between ‘50s and ‘70s of the last century, important examples of reinforced and prestressed concrete bridges were built in Italy by the…