Anchoring System
The ONGUARD seismic system is world-class and world-leading. ONGUARD`s anchors are welded to the tank and connected to the tank’s foundation or supporting structure, and are designed to hold down the tank during an earthquake and subsequent aftershocks. The energy-dissipating element within each ONGUARD anchor acts like a sacrificial fuse; it yields in both tension and compression throughout cycling earthquake accelerations, absorbing destructive energy and preserving the integrity of the tank, its foundation and connected infrastructure. ONGUARD`s pioneering design approach limits strains to an acceptable level in a design-level earthquake, safe in the knowledge that should something more severe strike - such as the 160%-of-code 2016 Kaikoura event - there is plenty of resilience on hand and the fuses could be quickly inspected and easily replaced, if recommended.
Unlike most other anchors seen today, the ONGUARD system fully meets the very specific requirement for ductile yielding anchors on liquid storage tanks that is mandated by Chapter 15 of ASCE 7, the American standard - cited by the Building Code - for design loads and associated criteria for structures.
REDUCE RISK TO
YOUR BUSINESS
Your product is the lifeblood of your business. The ONGUARD seismic system ensures your liquid is held safely and securely within your tanks throughout an earthquake and subsequent aftershocks.
THE ONGUARD DESIGN APPROACH
ONGUARD uses a capacity design approach and tunes its anchors to protect each tank with 100% efficiency. ONGUARD’s system exceeds building code requirements and sets the benchmark for global industry best practice.
Traditional liquid storage tank anchors – even if they are code-compliant – permanently elongate, or even fracture during an earthquake, allowing the tank to rock back and forth, uncontrolled, resulting in severe buckling, fracture, collapse and loss of contents.
Traditionally, tank anchors are not designed with the entire structural system in mind. ONGUARD takes an holistic approach to ensure that each part of the system works in structural harmony with the others.
ONGUARD`s seismic anchors dissipate harmful earthquake energy and keep tank movement to a minimum. The anchors stabilize the tank by continuously yielding in both tension and compression with cycling earthquake accelerations.
ONGUARD`s anchors form the backbone of a system which protects the structural integrity of the tank, its contents, connections, and the supporting structure throughout an earthquake and its aftershocks.
ONGUARD’s anchoring system is unparalleled and unequalled on a global scale.
The key component of ONGUARD’s seismic anchoring system is the patented energy-dissipating anchors which are manufactured to exacting standards for each tank. The raw materials are specifically selected, lab tested, and certified for quality and performance.
ONGUARD anchors are provided as part of the ONGUARD system and delivered duty-paid to you, your contractor, tank builder or installer with minimal fuss.
Detailed drawings, methodologies and specifications are provided to assist with installation and assure that our standards for quality and performance are maintained. Installation of ONGUARD’s anchors is considered to be simple, however ONGUARD representatives or partners are always on hand to provide technical advice before, during and after installation.
ONGUARD does more than simply supply anchors; we take a lead role in the design space, working alongside other stakeholders to ensure that everyone is on the same page.
Each system is carefully designed by ONGUARD’s engineers taking into consideration the seismic hazard and soil conditions for each location. This design is conveyed in the form of detailed design documentation and specifications produced by ONGUARD.
ONGUARD delivers an end-to-end service, overseeing installation to maintain assurance of quality, and offers a 3-yearly inspection schedule to provide the ultimate peace of mind.
ONGUARD’S SEISMIC
ENGINEERING EXPERTISE
ONGUARD is the earthquake protection expert for aboveground storage tanks and our experience has shown a holistic design approach is required to ensure dependable seismic performance. Our seismic system, which considers the tank, anchors, foundation, and connected infrastructure, is the most innovative on the planet, and its performance was proven in a M7.8 earthquake.
The ONGUARD system can be applied to new construction or retrofitted to existing tanks to introduce dependable earthquake protection.
OUR ANCHOR & DESIGN APPROACH
The ONGUARD system uses a capacity design approach using its patented OG PRO ductile anchors. These anchors concentrate damage from seismic loading into one small replaceable component, and provide protection to the tank, its contents, and attached infrastructure.
The replaceable component is machined to meet 100% of the structural demand and designed to retain its ductility after a design level event. It’s a highly resilient component that can withstand events far in excess of design level.
Earthquake engineering 101, applied specifically for liquid storage tanks.
CODE COMPLIANCE
The ONGUARD system is designed using globally-recognized standards and guidelines including:
- API 650
- ASCE 7
- AWWA D100
- NZS1170.5
- NZSEE ‘Seismic Design of Storage Tanks’ 2009 Guideline
Our Professional Engineers (PE) and Chartered Engineers (CMEngNZ) ensure compliance with local building codes and international best practice is met. We provide certification for the entire structural system to assist with the permitting process.
OUR RESEARCH
ONGUARD developed its own advanced research to better understand the actual behavior of an aboveground liquid storage tank during an earthquake. This research found a hybrid antisymmetric, ductile-elastic, and ductile-plastic anchor force distribution best matches the actual forces that the base of a tank encounters during an earthquake. ONGUARD adopts this research as the basis for its designs, guaranteeing accurate and 100% efficient solutions.
We`re more than happy to answer questions about this pioneering design approach.