Mexico’s College of Engineers indicates that 32% of the 11 kilometers of the elevated section have defects that must be addressed with specialized equipment; suggest not to resume service.
MEXICO CITY, (June 18, 2021).- The College of Civil Engineers of Mexico recommended not to resume the service on Line 12 of the Metro, due to the fact that more deficiencies were found in welding, cracks in beams and water leaks, mainly in the elevated section that the company Carso Infraestructura y Construcción SA de CV ( CICSA ) and that collapsed at the Olivos station on May 3.
In the physical inspection carried out on the route that is still standing, the coordinator of the Technical Committee for Structural Safety of the College of Civil Engineers, Bernardo Gómez González, reported that 32% of the 11 kilometers of the air route, which corresponds to CICSA, present failures classified as grade B, that is, they must be addressed with specialized equipment.
According to the opinion of the review, in the section from the Periférico Oriente to Zapotitlán station (8.3 kilometers), questionable welds were found, insufficient spacing of beams, columns with superficial cracks in columns, girders and heads, misaligned diaphragms in steel girders, and inconsistencies in horizontal stiffeners.
There are also deformed or partially deformed support elements in beams, diaphragms placed poorly or missing; shorter horizontal stiffeners in some areas.
“Evidence of deficiencies and other vulnerabilities that require further study were detected, specifically in this percentage that we are talking about in the sections that were rated grade B,” said the coordinator.
The ICA section, which includes 3 kilometers from Culhuacán to Calle 11 and from Tlaltenco to the Tláhuac terminal, did not present any damage with grade B.
Priority attention was recommended on the separation between the Periférico vehicle bridge and Tláhuac avenue with the columns of the elevated viaduct of Line 12, and supervision of the reinforcement carried out in the section near the Nopalera station and the repair of cracks and water leaks.
Therefore, the committee recommended not to restart the operation of the elevated section of Line 12 until the detailed review is made, level 2 and 3, if applicable, and the corresponding vulnerability report is obtained, which will be in the following months.
In the underground section, from Mexicaltzingo to Mixcoac, the tunnel expert from the College of Civil Engineers of Mexico, Francisco Suárez Fino, explained that it does not present structural damage, but it cannot be reopened until the elevated viaduct is repaired.
The foregoing is due to operational issues and intensive maintenance that require tracks and trains on Line 12, which must “be carried out in the Tláhuac workshops to meet the quality levels required to provide safety on the operation .”
He clarified that the decision was made by the Mexican Institute of Transportation, STC, Metro Union staff, the Ministry of Works, the Construction Safety Institute, and the College of Engineers.
He pointed out that anomalies were detected in the section, such as serious problems of seepage and water runoff at stations such as Mexicaltzingo.
Despite this, the expert affirmed that the tunnel does not have structural damage or deformations that put its stability at risk, but the structure of the tracks presents several problems, so it is necessary to change the most affected ones and not generate excessive expenditure on maintenance.
The Secretary of Works and Services, Jesús Antonio Esteva Medina, explained that the thousands of users of Line 12 will have an immediate response, which is why they are already working with the Technical Committee for Reinforcement and Rehabilitation to have an executive project in one month, approximately .
After the physical inspection report, the Head of Government, Claudia Sheinbaum , said that with the construction companies they are going to establish a technical table.
Regarding the recommendations made by the specialists, she said that some of the recommendations for other lines are already under attention.
Source: El Universal