Type: Residential
Date: 2019
Area: 2,000 sqm
Location: Tehran, Valiasr St.
Client: Parsian Esteghlal International Hotel

The seismic retrofitting and structural enhancement project of the Parsian Esteghlal Hotel in Tehran stands as one of the most sensitive and precise engineering endeavors for high-importance structures. This project was initiated with the primary goal of aligning the building with the latest seismic codes (Standard 2800) and elevating the structural performance levels against potential seismic events. As an architectural landmark of modern Tehran, the Esteghlal Hotel possesses unique physical characteristics, making any structural intervention dependent on rigorous dynamic analysis and a profound understanding of the existing lateral load-bearing systems. The strategic focus of this plan was directed toward reinforcing the lateral systems in the lower levels, particularly within the lobby, as this area plays a critical role in the overall stability of the tower due to its high ceiling clearance and the concentration of gravity and lateral loads.
In the initial phase, comprehensive assessments of the existing columns and their shear capacities were conducted, leading to a reinforcement strategy for the columns (highlighted in green in the models) using modern confinement methods such as structural jacketing. However, the distinguishing feature of this project lies in the addition of new shear walls (represented as red elements in the plans). These reinforcing walls have been strategically positioned to absorb the maximum share of lateral seismic forces while ensuring minimal disruption to the hotel’s open spaces and public areas. Engineering analyses demonstrated that by symmetrically distributing these walls within the floor plan, the center of mass and the center of rigidity could be brought closer together, thereby minimizing the torsional effects—one of the primary causes of structural failure during earthquakes.
The ingenuity of this design resides in the seamless integration of these rigid concrete walls into the architectural fabric of the lobby, where structural engineering transcends being a mere necessity and becomes an opportunity for spatial recreation. A major challenge in retrofitting public buildings is concealing or integrating reinforcing elements into the interior design. In this project, by redefining the layout of the information counter and service areas, the new reinforcing walls were conceptualized as functional boundaries and modern dividers. For instance, relocating the current information counter to the proposed new position allowed a primary shear wall to be situated behind it; this not only fulfilled the structural requirements but also facilitated a sophisticated separation between administrative sections and the public lobby.
Ultimately, the execution of this plan, while guaranteeing the seismic safety of guests and protecting a national asset against unforeseen disasters, has led to the optimization of circulation paths and the modernization of the hotel’s interior lobby space. The executive management, considering the hotel’s active operation, phased the reinforcement operations to maintain hospitality standards throughout the construction process. This integrated approach—where computational engineering, interior architecture, and strategic operational management converge—has transformed the Esteghlal Hotel’s structural enhancement project into a premier model for the seismic retrofitting of historic and high-rise buildings in Iran.