TSX Broadway: Structural Engineers Transform Times Square

by Benjamin Alper, PE

 

Projects like TSX Broadway and Palace Theater highlight Severud’s thoughtful and unique approach to redevelopment. This $2.5 billion project redefined what’s possible by combining old-world charm with modern engineering. The result is a dynamic entertainment, retail, and hotel complex that celebrates the old, and embraces the new.

TSX Broadway Redevelopment: A Groundbreaking Achievement

The TSX Broadway Redevelopment project was completed in May 2023. This project involved shifting and reassembling portions of the iconic Palace Theater, requiring the application of innovative engineering solutions and intricate structural work that demonstrated one of the most impressive structural engineering feats in the industry.

An Iconic Landmark, An Exceptional Challenge

The Palace Theater has remained a celebrated landmark in one of the busiest intersections of the world, New York City’s Times Square. This historic venue’s unique interior has always needed more room. This gave birth to the idea that pushed the boundaries of structural engineering to greater heights – quite literally!

TSX Broadway – Reinforced Concrete Ring Beam before wall demolition and theater lift

Elevating the Historic Palace Theater

One of the extraordinary features of this project was raising the Palace Theater building by 30 feet. TSX Broadway structural engineers remodeled the original eight-story steel-framed podium and 36-story concrete hotel tower. This was required to create the much-needed ground-floor space and improve accessibility for millions of visitors.

The Story of a Complex Transformation

The existing building was a hybrid structure occupying a significant portion of the site, and required a delicate balance of demolition and reconstruction. Severud engineers addressed the complex structural requirements by extending super-columns and partially demolishing the hotel tower to facilitate a novel transfer system.

Three colossal post-tensioned concrete girders were installed; each 44 feet deep and 140 feet long. These concrete girders were gradually assembled in four lifts to bear the structure’s massive load, demonstrating how an incredibly complex problem can be solved using the power of modern engineering.

Foundation Strengthening

To support the increased loads from the new structure, Severud engineers upgraded the existing super-columns by reinforcing them with high-strength concrete. Some of the existing columns were replaced with entirely new, stronger concrete columns. Columns below the transfer systems were demolished and remaining concrete slabs were reinforced to hang from the transfer girders for improved stability.

 

TSX Broadway – Panorama from Times Square

Accomplishing the Remarkable Palace Theater Lift

Imagine raising a 1700-seat theater, complete with its intricate interior, 30 feet off the ground. This jaw-dropping feat was the most extraordinary part of the project. Although it seemed improbable, Severud’s structural engineers accomplished this verify thing by designing concrete ring beams under the theater’s load-bearing walls where 34 jacking posts were installed and anchored to bedrock. These posts were carefully synchronized, allowing the theater to be raised in small increments, enabling the construction of new floors beneath.

 

Severud considers the transfer girder system and the lifting of the Palace Theater to be a significant technical accomplishment of the TSX Broadway Redevelopment project. This unprecedented undertaking underscores the ability of engineering to achieve remarkable results.

The Rise of a New Tower

With the successful theater lift, the construction of a new 32-story hotel tower began from the transfer level. While the Palace Theater floated above, the sleek hotel structure was built using reinforced concrete columns, core walls, and flat plate floors. Transfer girders were post-tensioned every 10 floors to manage stresses and limit deflections. This meticulous process made sure that the tower construction proceeded smoothly. With every successful step, the effectiveness of the transfer system became more apparent.

Installation of Caissons and Sub-Cellar Excavation

The TSX Broadway structural engineering project also included excavation for a new sub-cellar. Caissons were drilled in the existing cellar, extending into bedrock to temporarily support jacking operations during construction. Some of these caissons were permanent, carrying loads from new or existing columns.

TSX Broadway: A Celebration of Sustainability

Severud’s structural engineers, who were involved in the design of the TSX Broadway redevelopment project, prioritized sustainability. This was not just a buzzword, but a core foundational principle from the very beginning. The project incorporated advanced sustainable features such as energy recovery ventilation, energy-use monitoring, a highly-efficient boiler, and smart building management system. In addition to this, the project retained 25% of the existing structure, thus minimizing waste significantly and decreasing the demand for new materials. All concrete was substituted with supplementary cementitious materials for up to 40 percent of standard cement, and used reinforcement made from nearly 100 percent recycled steel.

 

This project not only set a new standard for sustainable urban development, but it also earned participation in New York City’s Zone Green program. It expands the limits of how existing structures can be repositioned and augmented to create improved functionality.

Bringing Light & Live Entertainment to Times Square

As the final part of the TSX Broadway redevelopment, the podium was wrapped in 18,000 square feet of LED screens, which open to reveal the Icon Stage that projects 30 feet above Times Square, lighting up the intersection.

Collaboration & Coordination At Its Core

TSX Broadway serves as a reminder that major engineering accomplishments are often the result of collective effort. The success of TSX Broadway Redevelopment was due to the seamless collaboration between the design and construction teams, and consistent coordination over a variety of interdependent operations.

Accolades & Honors

TSX Broadway reshaped the landscape of Times Square and garnered widespread recognition for its structural ingenuity.

It received the ‘2023 SEAoNY Excellence in Structural Engineering Award’ for demonstrating creativity, complexity, innovation, exceeding client needs, and sustainability.

 

The project also won the ‘2023 ACECNY Engineering Excellence Award’ for its uniqueness, future value, social and economic benefits, and successful client fulfillment.