Gerb - Vibration Control Systems
(for Mitigation of Vibration and Structure-Borne Noise)

GERB Schwingungsisolierungen (GERB Vibration Control Systems) was established in 1908 for the vibration isolation and noise control of machinery. The company's involvement in trackbed isolation and the design of the GERB floating trackbed system was the logical result of earlier activities in other areas of vibration control. GERB systems consist of helical steel springs, and if needed, Viscodampers (VISCODAMPERS™ USA).

GERB FLOATING TRACKBED SYSTEM

The spring-supported GERB system consists of either a simple concrete slab with direct rail fixing or a trough type cross section with a ballast bed and spring elements embedded in the slab or placed in recesses along the outside of the trackbed. The GERB floating trackbed system offers favourable and cost-saving details:

• The trackbed is cast on top of the supporting structure, avoiding expensive formwork
• The trackbed can be cast in long sections thus reducing the number of joints
• Height adjustment and post-alignment of the trackbed is easily possible at any time by means of the springs
• The low natural frequencies of 4HZ to 8Hz result in high efficiency in vibration and structure borne noise control; compared to other floating trackbed systems, the transmission loss in the GERB system is approximately 10dB better over the entire frequency range up to approximately 200Hz, and even more in the low frequency range

The GERB isolation system permits access, inspection, and even easy replacement at any time. In spite of all these favourable facts, the overall system cost is the same or even less than other floating trackbed systems.

REFERENCES

• Tram lines in Cologne, Frechen, Bielefeld and Stuttgart (Germany),
• Heavy rail tracks in Sao Paulo and Brazilia (Brazil), and Puchon (Korea)
• High speed track (TGV) in Chonan (Korea)
• Light rail track in London (UK), Berlin (Germany) and Charlotte, NC (USA)
• Passenger-transfer-system at Frankfurt International Airport (Germany)
• Metro lines in Beijing, Shanghai, Shenzhen, Nanjing and Guangzhou (China)

ACTIVITIES

Over the last century, GERB has developed, influenced, or at least accompanied all major new applications in vibration control, including the elastic support of the largest steam turbines in the world, the introduction of direct spring support of forging hammers and sonar protection systems on naval ships. Large testing equipment including earthquake shaking tables, rocket test stands and even entire buildings are today supported on GERB elastic support systems.

GERB, the worldwide leader in vibration control of heavy equipment and structures, has put more than 500 buildings with a maximum weight up to 50,000t on springs for vibration isolation, seismic isolation or protection against subsidence.

THE CORPORATE GERB GROUP

GERB Vibration Control Systems has its headquarters and its main manufacturing facilities together with its R&D division in Berlin, Germany. The main technical office, including GERB ENGINEERING, the civil engineering subsidiary company within the GERB group, is located in Essen, Germany.

Independent subsidiaries in other countries are 100% owned by the parent company in Germany wherever permitted by local laws. All offices are staffed with top specialists in vibration control.

GERB offers a number of services:

• Vibration measurements
• Design of vibration control systems
• Design of the spring-supported structures, including static and dynamic analysis
• Preparation of site drawings
• Supervision of system installations and inspections