Design of Steel Structures for the Expansion of Westfield Černý Most

Customer's Needs

The Černý Most Center opened in 1997 as the first major shopping mall in the Czech Republic. The recent expansion seamlessly integrates with the previous two construction phases, with the first phase starting in 2000. The primary challenge of the Westfield Černý Most shopping mall extension was designing and analyzing the complex steel load-bearing structure while ensuring seamless integration with the existing building.

The project required the creation of a steel framework for the new flat roof, skylight, and inserted floor, all while addressing the unique structural needs of connecting the new extension with the existing building. Additionally, the design had to accommodate dilatation motions between the old and new parts of the mall, ensuring the stability and safety of the entire structure.
The engineering team also faced the challenge of ensuring that the design could support the weight of the new loads without compromising the building's overall performance or appearance. These factors required advanced modeling and precise calculations, which were achieved using RFEM.

The total height of the structure reaches level +17.420 m (57.152 ft), and the steel structure is placed on a new reinforced concrete structure at level +6.150 m (20.177 ft), with pendulum bearings to ensure dilatation motions between the new and existing buildings.

Implementation

The implementation of the structural design for the extension of the northeast corner at Westfield was powered by RFEM. The software was used to model and analyze the steel structure, incorporating essential components like truss girders, roof purlins, secondary beams, and a skylight frame to support the expanded food court.

RFEM’s advanced capabilities facilitated the integration of pendulum bearings to manage movement between new and existing sections, while stiffeners were strategically placed to enhance structural rigidity. This software-driven approach ensured an efficient, stable, and cost-effective solution for the project’s complex design requirements.

The architectural design of the project comes from the renowned London-based firm Benoy, which has long been associated with the design of modern and sustainable shopping centers around the world. The ongoing expansion builds upon the previous phase of construction, which started in 2000. Throughout the entire construction process, the shopping center remains fully operational. The expansion also introduces a new architectural expression for the center, defined by the dominant extension in the northeast part of the building.

Results

The results of using RFEM for the Černý Most shopping mall extension project provided a detailed structural analysis, including key aspects such as displacements, internal forces, and stress distribution for the steel load-bearing structure. The software enabled precise calculations for the design of truss girders, roof purlins, and secondary beams, ensuring optimal structural performance under various load cases.

The Import Support Reactions feature in RFEM significantly reduces manual work by automating tasks that would otherwise take hours, greatly improving efficiency.

Optimizing the steel staircase design saved over 50% in construction costs, highlighting the value of early-stage optimization and collaboration.

Dlubal Software’s RFEM and RSECTION ensure high accuracy and efficiency in reinforced concrete design, streamlining the workflow.

Why Dlubal Software

Dlubal provides a reliable basis for your design processes. Since the company's establishment in 1987, Dlubal Software has focused on developing intuitive and efficient software solutions for static and dynamic analysis, CFD analysis, and structural design.

• Rapid creation of multiple models – from a basic frame model to a detailed wall-and-frame model.
• Stability assessment – identification and verification of critical beam states at various stages of launching.
• Structural optimization – efficient design considering variable nose length and future reuse.
• Nonlinear analyses – refinement of results and verification of structural behavior under extreme loads.
• Integrated cross-section calcs – precise definition of the complex beam cross-section in SHAPE-THIN 8.

Software Used

For this project, RFEM was used to analyze and design the steel structure for the Westfield Černý Most shopping mall extension, ensuring the stability and proper integration of key components like truss girders, roof purlins, and the overall steel framework.