An anchor cage is an engineered arrangement of bolts secured by top and bottom steel rings, referred to as setting templates. As these components come together, they form a distinctive cage-like structure. This cage is what creates a solid and stable foundation for structures being placed in the ground. An anchor cage provides a solid base capable of withstanding the forces exerted by the structure it supports. Think of it as a reliable anchor, securing structures firmly in place while mitigating any unfavorable conditions that may arise. With an anchor cage in place, construction projects can gain the essential foundation necessary for success, ensuring longevity and strength for years to come.
Benefits of A Foundation Anchor Cage
Anchor cages provide additional stability for structures with larger loads and enhance the overall stability of these structures. The anchor cage prevents the overall structure from being displaced by external forces acting upon it. The cage does this by distributing the load across the entire foundation, which adds resistance against pullout forces. On the other hand, direct embed structures are placed directly into the hole without additional support. These structures rely on the resistance provided by the backfill materials such as dirt or concrete after they are placed. Anchor cages are traditionally used for larger load structures, such as at the entry points of a substation, at dead-end structures, and at angles where transmission and distribution lines change direction. These structures are required to handle the increased loads and stress of these areas.
Anchor cages also afford the opportunity to provide leveling nuts for installation and maintenance. Leveling nuts play a key role in the installation and maintenance of structures such as poles. These nuts, located at the bottom of the threaded portion of the bolts, allow for fine adjustments to achieve the desired level and alignment. By adjusting the nuts, installers can compensate for uneven ground surfaces or make minor corrections to ensure the structure is perfectly level.
Foundation Anchor Cage Installation
To start a job, the process begins by accessing what materials will be needed. Engineersgather information from factors such as soil samples, weight of transmission lines, prevailing winds and potential ice accumulation before running calculations for design. Depending on the size of the structure, materials for bolts can range from mild steel to heat treated.
How does it work?
The cage is held in place over a prepared hole
The cage is then attached to the concrete reinforcing rebar
The hole is filled with concrete, forming a foundation
After the concrete cures, the top setting template is removed
Removing the template leaves bolts projecting out to match the baseplate holes of steel structures, such as poles.
The structure is then attached with nuts
The cage more effectively transfers the loads from the structure to the foundation. When installing the cage it’s also important to know what material you’re using for the project.
The Role of Material Properties in Anchor Cage Design
In power infrastructure projects, material selection plays a crucial role in ensuring the durability and functionality of various structures. Substations, where electrical power is transformed and controlled, commonly rely onF1554Gr55 (Mild Steel).It’s a versatile and cost-effective option that provides the necessary strength to support the majority of equipment inside.
On the other hand, for transmission and distribution structures such as towers and poles that support power lines, A615Gr75 rebar is the preferred material. This grade of rebar offers enhanced strength and resistance to external forces, ensuring the stability and reliability of transmission and distribution lines. Additionally, in the construction process, setting templates, which are vital for accurate installation, are typically manufactured from mild steel. Mild steel’s malleability, ease of fabrication, and affordability make it an ideal choice for creating setting templates that can be easily adjusted and customized to meet specific project requirements.
Value Added Services
One major challenge is designing a cage with enough safety factors to withstand the demands of transportation, loading, unloading, stacking, storage, delivery, and crane service. Engineers take into account all the potential stresses and strains that the cage will face throughout its journey. Our team takes great care in packaging and securing each cage for transportation. Anchor cages can be shipped assembled and ready to be installed, or the parts for the cages such as the bars, plates, nuts, and washers can be shipped unassembled.
Storage options are available for the anchor cages should changes occur in delivery. Not only are there storage options available, having a variety of shipping options also come in handy when handling a request for receiving materials.
Concrete reinforcement rings can be attached to the outside of the cage for increased stability of the foundation. The concrete reinforcement ring is a circular structure that is made of steel bars or mesh that will enhance the strength or stability of the cage, providing structural integrity and load-bearing capacity.
Lifting lugs are another option available for the anchor cages. The lifting lug is an attachment designed to ease the lifting and transportation of the cage during the installation or relocation processes.
Weld tags are attached to every anchor cage to ease confusion. Each weld tag will have the structure numbers and or lay down yard information to ensure the product is correct and save time during storage, shipping, and project management.
Wire ties can be added to make sure nuts remain intact during transportation. To reinforce the stability of the cage during logistics handling, angle bracing can be added.
Angle bracing for an anchor cage is a diagonal structure, usually made of steel that will reinforce and stabilize the cage. By doing so it increases its resistance to lateral forces such as wind or seismic loads, which can exert pressure from the sides. The bracing helps distribute these forces throughout the cage, reducing the risk of deformation or failure.
Stiffener rings can be welded to the top template to ensure the integrity of the bolt circle remains intact during handling.
V-Notches are placed on the template to guarantee the cage is installed properly in the correct position.
30 Years of Cage Excellence
The proof is in the people! Our teams are dedicated to providing the best customer service experience and high quality work done right the first time. Our in house manufacturing and distribution teams cover everything from threading, plate cutting, galvanizing,shipping, and more. TFI anchor cages are processed from start to finish within one square mile area, creating the ability to make adjustments quickly. Our team has over 30 years in the cage business and we are dedicated to maintaining our standards of quality and service. With over $16 million in inventory and 17 distribution facilities across the southeast we can ensure your project remains on schedule. We believe in a simplified way of doing business that starts with qualified personnel that thrive on customer satisfaction and product knowledge. Our teams are dedicated to getting it done right the first time. If you are interested in speaking to one of our industry specialists contact us today at info@threadedfastenersinc.com or contact
Don Searcy, Senior Strategist for Business Development at dsearcy@tfmfg.com.
