Who We Are

Who We Are

Hercules Structure, Joint and Vibration Isolation Systems have been used in thousand of projects throughout the world since its establishment in Australia in 1972. They are technically mature and have gained a reputation for their quality products and technical expertise.

Email us at: info@hercules-structures.com Follow us on:

Lock-Up Device

  • A lock-up device, a type of shock absorber for bridges and structures, is shown undergoing testing in a lab. The black and silver device is mounted on heavy-duty red steel plates bolted to a concrete floor.
  • A close-up of a black lock-up device with logos for UPM (Universiti Putra Malaysia) and Hercules. The device is mounted on a yellow stand for display.
  • The lock-up device is shown isolated on a white background, mounted on its red testing plates.
  • An angled, high-view shot of the lock-up device on its red testing mounts, isolated on a white background.
  • A brochure page for the "Lock-up Device" explaining its use in preventing earthquake damage to bridges. It shows a picture of a collapsed bridge, a diagram of how the device is installed, and an image of the device itself. The patent filing number and inventor are also listed.
  • A brochure for a "Lock-up Device" from Hercules Structures. The brochure features an image of the device, a technical graph of its performance (Force vs. Displacement), and contact information for the company in the USA and Malaysia. It also includes information about ARCS3D software for seismic analysis.

The Hercules Lock-Up Device is a vital seismic protection system for modern bridges. Specifically, it controls excessive movement at expansion joints. As a result, it prevents unseating and seismic pounding during earthquakes, which ensures the long-term structural integrity of the bridge.

Seismic Protection for Bridge Expansion Joints

The Hercules Lock-Up Device is an advanced structural damper that protects bridges from seismic damage. It achieves this by controlling excessive movement at critical expansion joints. For example, earthquakes can cause the bridge deck to slip off its support, which is known as unseating. Alternatively, adjacent sections of the bridge can strike each other, causing seismic pounding. These two catastrophic failure modes have been a significant concern in previous seismic events. Therefore, the Hercules Lock-Up Device addresses these vulnerabilities to safeguard the bridge’s structural integrity and ensure its resilience.

How the Hercules Lock-Up Device Works

This innovative device uses a two-stage damping action to respond to both normal and seismic conditions. Under everyday conditions, for instance, the system’s high-pressure resistance damper allows for controlled thermal movement. However, during a seismic event, an orifice system activates a secondary stage. This action immediately accelerates damping and absorbs the violent energy from the earthquake. In short, the device acts quickly to “lock” the joint, which prevents displacement and mitigates the risks of failure.

Developed by Assoc. Prof. Dr. Farzad Hejazi

Assoc. Prof. Dr. Farzad Hejazi, a recognized expert in structural dynamics, developed the Hercules Lock-Up Device through his research. This patented (PI2018701536) two-stage damper technology represents a significant advancement in bridge engineering. Ultimately, it offers unmatched protection during earthquakes and reduces the risks of costly repairs and catastrophic failures.

Key Benefits of Hercules Lock-Up Device

  • Prevents Unseating. Maintains the gap at expansion joints during seismic events. This consequently avoids costly bridge deck unseating and enhances safety.

  • Mitigates Seismic Pounding. Effectively reduces seismic pounding—the violent collision between adjacent bridge sections—by controlling excessive movement.

  • Enhanced Seismic Resilience. Provides enhanced seismic protection to ensure the stability of bridges. This, in turn, increases their lifespan and minimizes downtime for repairs after an earthquake.

  • Two-Stage Damping Action. The two-stage damping system quickly absorbs energy during seismic events, thereby offering immediate protection from sudden movements and impacts.

  • Custom-Engineered Solutions. We customize each Hercules Lock-Up Device to meet your project’s unique needs, including specific stroke lengths and pressure capacities, ensuring optimal performance.

  • Durable and Reliable. We design the device to withstand harsh environmental conditions. As a result, it functions effectively throughout the lifespan of the bridge.

Applications of the Hercules Lock-Up Device

The Hercules Lock-Up Device is ideal for modern bridge construction and seismic retrofitting. It is particularly effective at critical expansion joints that are vulnerable during earthquakes. Furthermore, it is beneficial for:

  • New Bridge Construction: Integrating the device during the design phase for long-term seismic resilience.

  • Bridge Seismic Retrofit: Strengthening existing infrastructure to meet modern seismic safety standards.

  • Transportation Infrastructure: Ensuring the safety and durability of highway bridges, railway bridges, and other vital structures.

Related Products :

Viscous Damper