According to the executive summary of the third report prepared by Det Norske Veritas (DNV) on the collapse of Line 12 of the CDMX Metro, four preventive “barriers” were identified and evaluated that, if effective, would have prevented the collapse of the line. interlock between the Tezonco and Olivos stations on May 3, 2021.
The first barrier has to do with design. The report, to which El Economista had access, stated that based on the review of documents, it was found that the requirements of the American Association of State Highway and Transportation Officials (AASHTO) were not met.
Such as that the cross frames were not directly attached to the bottom flanges of the beams.
“Failure to meet these AASHTO requirements during design is a root cause of the incident,” the report reads.
DNV confirmed that the certification of the civil engineering works was not carried out; he described this situation as the second barrier.
He recalled that the supervision of the civil engineering works was carried out by LYTSA, IAC, EI and DGPM, but “no documentation related to due diligence was provided to DNV” on the matter by these supervisory entities.
The third barrier has to do with the installation of the bolts; The document detailed that the field inspection carried out by DNV personnel identified significant deficiencies in its installation.
Approximately 30% of the western section bolts “were either not installed or were installed so poorly that there are no obvious indications of residual welding.”
Lastly, DNV confirmed that the failure to carry out inspections of the elevated section and comply with the inspection requirements of the maintenance manual is a root cause of the incident.
He specified that the L12 manual establishes that routine reviews should be quarterly, semi-annually and annually, depending on the year of service. The firm confirmed that it did not receive documentation proving the above.
However, it did obtain review reports after the 2017, 2018 and 2020 earthquakes “as well as the ISSA inspection in 2019.”
DNV also detailed that through historical images in Google Street View and a review made by drones in 2019, deformation and buckling of the longitudinal stiffeners in the beams, negative vertical deflection in these and the deflection of the central crossbar can be seen. However, there is no evidence (documentation, data or otherwise)” provided to DNV to indicate that these routine inspections were carried out.
request appearance
After the refusal of the capital government to accept the third and last DNV report, victims’ advocates requested that the head of government, Claudia Sheinbaum, appear.
Teófilo Benítez Granados, defense attorney for 12 victims and their families, announced that they requested the Public Ministry (MP) the appearance of the president to offer or exhibit the opinion and, if she refused, he said, they would take the case before a control judge so that this act of investigation is transparent.
“Unfortunately we have experienced various acts where many people who have been requested to be charged have been protected and they have not done so,” he said.
The lawyer argued that they have their own expertise that also shows a lack of maintenance during the administration of Miguel Ángel Mancera and Sheinbaum.
Therefore, the refusal of the capital government would not affect its legal process since since then there is evidence of hidden defects due to lack of maintenance and supervision.
He considered that the controversy over DNV’s expertise “is a political issue, where they are covering up the responsibility of certain personalities, which affect both the government of Miguel Ángel Mancera and the current government.”
He added that the victims “are committed so that it does not happen again and that other families do not go through what they have gone through,” he stressed.
On the other hand, the lawyer Cristopher Estupiñan, who represents another 14 affected, indicated that they will not change the strategy, since from the beginning they determined that they would not include the expert opinion of the capital government, since they also had their own opinion.
“We have based ourselves on the one made by the prosecution and on our own, but the fact that they are now refusing to exhibit it is really for political reasons, because there is no other explanation that justifies it,” he said.
The defender stressed that the lack of transparency on the part of the capital government leads to showing that citizens are helpless in this type of process.
And he maintained that no additional appeal will be filed since it is up to the CDMX government to delimit responsibilities, in addition to not seeking that the victims enter into a political game in the case.
Layout and construction were the cause of the collapse, insists Sheinbaum
After releasing the third report from the DNV company on the collapse of a section of Metro Line 12, the head of the CDMX Government, Claudia Sheinbaum, reiterated that said report did not comply with the agreed methodology.
In a conference, the president of the capital commented that the rejection of the report by her government derives from the fact that it is determined that maintenance has the same weight, for the collapse of the beam, as the flaws in the construction and design of the so-called Golden Line. .
“You can’t put everything on the same level, plus there are all the maintenance logs,” Sheinbaum said.
The head of government concluded that the subject of inspection in the maintenance of Line 12 during her administration has been carried out and said subject “cannot be the cause of the collapse of the beam.”
For his part, the Secretary of Mobility of the CDMX, Alejandro Lajous Loaeza, indicated that the third report should have focused on the findings on deficiencies in construction and design that the second report produced.
“These causes are the ones that should have been relevant to what they call, in report three, the ‘Barrier Analysis,'” he said.
And he added that the denomination of “barriers” is how DNV names the “elements that could have, in a certain way, prevented these errors from having the consequences that they had, for example, it can be: if the bolts are poorly placed , the supervision on the placement of the bolts”. (Drafting)