An independent auditor's report publicized by the Mexico City government on Tuesday revealed that missing bolts, beam flaws, and poor welds were the contributors to the metro crash that happened in the city in May.

The said analysis with 180 pages was done by Norwegian company DNV, making it the latest installment of their technical opinion on the metro tragedy that killed more than two dozens of individuals.

Report Reveals Contributors on Mexico Metro Crash

It can be recalled that Mexico City hired DNV to determine the causes of the fatal accident in May. The latest report by the Norwegian company had the same conclusions as to their preliminary report in June, ABC News reported.

The latest report, which was also DNV's final technical report on the metro, revealed that the collapse happened due to the lack of functional bolts on a "significant stretch of the line" which is led to the north and south beams. Furthermore, the inadequate bolts "caused a part of the elevated section to lose its composite structure," France 24 reported.

The said elevated structure also served as "two independent parallel beams, concrete beam and steel beam, experienced loading conditions for which they were not designed."

As a result, the deficiencies created conditions that "distorted the central transverse frame," promoting fatigue cracks that reduced the capability of the structure to support the load.

Other possible reasons for the collapse also mentioned in the report included mechanical and design deficiencies in the metro's framework. Poor welding practices were also observed by the auditor.

Sections of Mexico's Metro Already Compromised Before Earthquake

Apart from revealing the cause of the metro crash in Mexico City, the report also revealed that the sections of the metro were already in "compromised condition" even before the 2017 earthquake that destroyed some parts of the line.

Jesus Estava, head of Mexico City's Public Works Department, said that the city government started working on the rehabilitation of the line. Estava noted that they will sign agreements with the companies that will be doing the work. Estava also highlighted that DNV's findings will be shared with a technical advisory committee.

The collapse also affected Mexican billionaire Carlos Slim, as one of his companies was involved in the construction of the section in the metro that collapsed. Slim was reported to agree to the reconstruction. However, the billionaire rejected the claims that the line had flaws in its original construction.

In June, Mexico President Lopez Obrador said that Grupo Carso, a company controlled by Slim's family and French train maker Alstom SA, would repair the line with no cost to the government so that it can reopen in a year.

It can be recalled that the Line 12 of Mexico City's metro system was built between 2010 and 2012 when Foreign Affairs Secretary Marcelo Ebrard was still the city's mayor. The city was forced to close the transit in 2014, to repair or replace the tracks, 17 months after it was opened.

This article is owned by Latin Post

Written By: Joshua Summers

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