Revolutionizing Elevator Systems for Skyscrapers: A Case Study

ThyssenKrupp Elevator, part of the Germany-based ThyssenKrupp Corporation, is one of the world's leading elevator companies. With sales of €6.4 billion and more than 50,000 employees at 900 locations, the company’s products are installed in buildings throughout the world. ThyssenKrupp Elevator’s design and engineering teams are known for their innovative solutions to the challenges posed by modern architecture. They developed an elevator system that uses electro-magnetic drives attached to the cabin frame, eliminating the need for roof-mounted cables and allowing the elevator to travel the full 800-meter distance of the world's tallest buildings.

The architecture industry is witnessing a trend of taller and more elaborate buildings, with the world’s tallest skyscraper, the Burj Khalifa, standing at 828 meters. This height brings unique challenges, particularly in transporting people from the ground floor to the top efficiently. Traditional elevator systems, which operate via cable systems located at the top floor of the building, offer a maximum ride height of up to 400 meters, just half the distance of the world’s tallest building. This necessitates passengers to ride two or more elevators to reach the top level. ThyssenKrupp Elevator, a leading elevator company, developed an elevator that uses electro-magnetic drives attached to the cabin frame, eliminating the need for roof-mounted cables and allowing the elevator to travel the full 800-meter distance. However, this new system could not carry as much weight as a traditional elevator. The challenge was to ensure the new design was as lightweight as possible to maximize the loading capacity of the cabins.

Altair ProductDesign was selected to explore methods and materials that could help minimize the weight of the design. They developed a three-stage approach. In the first stage, a topology optimization study was performed on the BackPack concept using OptiStruct, a design optimization solution within Altair’s HyperWorks suite of simulation tools. The software suggested the most efficient layout of material for the cabin's structure while meeting design requirements. In the second stage, the thicknesses of the materials were investigated. The team explored the lightweight potential of sandwich panel structures where aluminium or plastic facing sheets are used with a foam core. Using OptiStruct, the team performed a sizing optimization process to explore the thicknesses of the wall facing sheets and the foam core. In the third stage, the team explored new materials, particularly carbon fiber, for the walls of the new cabin. An optimization study was developed to find the ideal thickness of material, fiber ply shapes, and lay-up orientation of each layer.

• The weight reduction project produced impressive results, giving ThyssenKrupp Elevator additional confidence in the electro-magnetic concept as a practical alternative to the cable system. The weight savings not only met the company's targets but also exceeded them, demonstrating the effectiveness of the optimization technology applied. The successful results from this project have motivated ThyssenKrupp Elevators to continue the development of the BackPack concept. The design has now advanced for further testing and prototyping, marking a significant step forward in the evolution of elevator systems for tall buildings.

• The BackPack structure, in combination with the sizing optimization of the sandwich panel walls, produced a cabin that was 42% less than the target weight.
• If the walls were constructed from carbon fiber, it would be possible to go even further, down to 56% below target.
• The SideGuide concept also saw weight savings, 16% lighter than target using traditional materials.