Newly Inaugurated Barranca River Bridge Faces Structural Risks
The bridge, opened in January, may collapse during significant earthquakes due to design deficiencies, warns national materials laboratory.
The Barranca River Bridge, located on the route between Caldera and El Roble in Puntarenas and inaugurated in late January 2023, has been identified as having structural risks that could lead to beam collapse during a significant earthquake.
This assessment comes from the National Laboratory of Materials and Structural Models (LANAMME), following inspections conducted last year before the bridge was opened to traffic.
The report indicates that should the beams lose contact with the bridge's supporting mass (abutments), there is a high risk of collapse due to a lack of evidence that the calculations for the contact area adhered to design regulations.
Additional findings in the report emphasize the potential consequences of a beam collapse, including unsafe transit over the bridge and subsequent road closures.
Inspections also revealed that the thickness of concrete covering the reinforcing bars of the bridge slab does not meet the minimum requirements outlined in international design standards for coastal bridges.
Moreover, asphalt samples taken from the site presented non-compliance with the parameters established during testing, although the quality of the concrete conformed to the contract specifications.
Engineers from LANAMME pointed to issues related to traffic management during construction, including the use of temporary barriers that varied from those recommended in regulatory guidelines.
In response to these findings, the project administration claimed that the methodologies used in structural design and traffic management were validated by internal criteria.
The audit, conducted from January through November of last year, examined the superstructure design, the implementation of the traffic management plan (TMP), and the quality of materials utilized.
A total of 18 technical visits were made to the project, during which 30 material samples were collected and 19 reports were issued.
LANAMME highlighted that technical standards aim to ensure the durability and safety of structures, allowing them to maintain functionality after seismic events and reducing maintenance costs.
Authorities were advised to adhere to these standards in future projects.
Additionally, the laboratory noted that traffic management has been a recurring issue in other reports, suggesting a heightened focus on controlling traffic during project execution.
During the inauguration of the new structure on January 31, authorities from the Ministry of Public Works and Transport (MOPT) assured that improvements to the bridge updated its compliance with seismic codes and increased its load capacity and earthquake resistance.
MOPT detailed that the intervention would allow the bridge to endure for at least 50 more years, with provisions for potential route expansion.
The reconstruction and widening of the Barranca River Bridge took 15 months, during which key elements including the roadway slab, beams, abutments, piers, supports, and expansion joints underwent significant work.
The total cost of the project was approximately 4.304 billion colones (about 7.2 million USD), an increase from the original estimate of 2.870 billion colones, attributed to delays, inadequate planning, and modifications to design, as revealed by the audit from the National Roadway Council (Conavi).
This assessment comes from the National Laboratory of Materials and Structural Models (LANAMME), following inspections conducted last year before the bridge was opened to traffic.
The report indicates that should the beams lose contact with the bridge's supporting mass (abutments), there is a high risk of collapse due to a lack of evidence that the calculations for the contact area adhered to design regulations.
Additional findings in the report emphasize the potential consequences of a beam collapse, including unsafe transit over the bridge and subsequent road closures.
Inspections also revealed that the thickness of concrete covering the reinforcing bars of the bridge slab does not meet the minimum requirements outlined in international design standards for coastal bridges.
Moreover, asphalt samples taken from the site presented non-compliance with the parameters established during testing, although the quality of the concrete conformed to the contract specifications.
Engineers from LANAMME pointed to issues related to traffic management during construction, including the use of temporary barriers that varied from those recommended in regulatory guidelines.
In response to these findings, the project administration claimed that the methodologies used in structural design and traffic management were validated by internal criteria.
The audit, conducted from January through November of last year, examined the superstructure design, the implementation of the traffic management plan (TMP), and the quality of materials utilized.
A total of 18 technical visits were made to the project, during which 30 material samples were collected and 19 reports were issued.
LANAMME highlighted that technical standards aim to ensure the durability and safety of structures, allowing them to maintain functionality after seismic events and reducing maintenance costs.
Authorities were advised to adhere to these standards in future projects.
Additionally, the laboratory noted that traffic management has been a recurring issue in other reports, suggesting a heightened focus on controlling traffic during project execution.
During the inauguration of the new structure on January 31, authorities from the Ministry of Public Works and Transport (MOPT) assured that improvements to the bridge updated its compliance with seismic codes and increased its load capacity and earthquake resistance.
MOPT detailed that the intervention would allow the bridge to endure for at least 50 more years, with provisions for potential route expansion.
The reconstruction and widening of the Barranca River Bridge took 15 months, during which key elements including the roadway slab, beams, abutments, piers, supports, and expansion joints underwent significant work.
The total cost of the project was approximately 4.304 billion colones (about 7.2 million USD), an increase from the original estimate of 2.870 billion colones, attributed to delays, inadequate planning, and modifications to design, as revealed by the audit from the National Roadway Council (Conavi).
