Jet Set Case: Expert points out structural failures and lack of preventive maintenance
Within the framework of the trial on the merits regarding the collapse of the Jet Set nightclub roof, which occurred on April 8, 2025, seismic engineer Eduardo Fierro appeared as the third expert witness presented by the Public Prosecutor’s Office. During his testimony, the expert warned that the concrete detachments prior to the collapse were clear signs of a structural failure in progress.
Fierro, who has a 52-year career and professional experience in various countries in the Americas and Europe, detailed that his evaluation was part of a multidisciplinary team together with Leonardo Reyes Madera and Máximo Corominas. The technical analysis included field visits, review of photographic records, and an exhaustive study of the materials recovered at the scene of the incident.
Modifications without technical support
One of the key points presented by the expert was the series of transformations the building underwent over the years. The property, which originally operated as a cinema, was adapted to function as a nightclub without, according to the investigations, the necessary structural calculations being performed to support the new loads.
- Installation of post-tensioned beams.
- Addition of four layers of fine concrete, reaching a thickness of approximately 37.5 centimeters.
- Placement of water tanks, air conditioning equipment, light fixtures, and heavy sound systems.
The specialist highlighted that the weight of the fines increases significantly when wet, which increases the load on the structure by between 20% and 40%. This constant overload, combined with the lack of engineering studies, would have severely weakened the stability of the roof.
The falling of concrete fragments was a direct indication of progressive deterioration. Had I been consulted at that time, my recommendation would have been to immediately suspend the establishment’s operations until a thorough evaluation of the building’s integrity was conducted.
Eduardo Fierro, seismic engineer and expert witness in the case.
Details of the judicial process
During cross-examination, the victims’ defense questioned the expert about other factors, such as the removal of a column for the construction of the stage. In this regard, Fierro clarified that, in his technical opinion, said removal was not the main trigger that caused the collapse, maintaining the focus on the structural deterioration accumulated by excessive loads and the lack of maintenance.
The report presented by the expert team used the ACI 318 standard from the American Concrete Institute as a reference, establishing a rigorous technical framework to determine the demanding forces and the actual resistance of the collapsed elements. The judicial process continues to advance with the goal of clarifying the criminal responsibilities behind this tragic event.
