Structural

Build, Design, and Install Towers and Other Structures

TOTAL STRUCTURAL SOLUTIONS FOR ALL TOWER AND CELL INSTALLATIONS

A solid foundation in tower fabrication. USA-STRUCTURAL is your one stop solution for creating and modifying foundations, platforms, and supporting infrastructure. Trust our experience and a track record of proven results.

Foundations Deep experience with complex foundations

At the foot of every vertical structure that supports wireless transmission equipment is the foundation. When the foundation fails, the entire structure (along with the equipment mounted on it) is in danger, not to mention the surrounding people and property. That is why it is vital to inspect and maintain the proper foundation. Should a problem arise, our teams of experts are ready to help with extensive knowledge of Caisson Mods, Micro-Pile, and Helical techniques to resolve the issue quickly and without service disruption.

When a new caisson is needed to either repair or replaces the existing one, lots of challenges arise. Due to the tight quarters that the work must be performed in, hand digging is usually required. This takes time and precision and special care must be given to ensure that existing building slabs and other structures on site are not compromised during excavation. Custom shoring plans are needed to ensure soils do not shift, and when digging more than 4 feet these are almost always needed. Tying into the existing Caisson requires precision and our teams can help complete the project with zero disruption in service.

When Helical Piles are the right choice for modifying foundations, the biggest challenge you can face is rock. Because these piles are usually not surrounded by concrete, the drilling process can cause voids in the drilling shaft if they encounter rock. If this happens the Helical will not pass structural load requirements and thus the project will be put on hold. In order to avoid this issue, proper analysis of soil samples is a must so that the right determination can be made before construction starts.

The Helical Pile solution is a good one and is usually less expensive than Micro-Piles, but if recommended in the wrong soil situation it can be expensive. Our teams of experts can help guide you to make sure the right decision is made.

When modifying a foundation without disrupting service, Miro-Piles are often used. The process starts with placing lots of Micro-Piles around the failed foundation. These “min-caissons” are made from steel shafts that are drilled into place, and are surrounded during the process with pumped grout material. Next, a steel rebar cage is assembled into an excavated area surrounding the existing structure. Doweling then occurs which involves drilling into the foundation and then epoxying a steel bar into the drilled hole. Once this is completed, concrete is added to “tie everything in”. All this is performed while the site is humming along can be a challenge, and our expertise can help.

Platforms Platforms designed to support your network

Platforms are the steel structures that hold the networking equipment usually found in a shelter, or housed in multiple cabinets. They must be resilient to the elements, built to exacting specifications, and enable carriers to keep their equipment organized and protected. That is why we use in house engineering, and in house fabrication to insure that our products are of the highest quality in our industry.

Ground-mounted platforms can be required if the site has a full compound and no room for additional equipment. Rather than trying to secure additional space, you can simply elevate the equipment with a platform. This is also a way to solve flood plain issues and keep equipment high and dry.

Either way, we start with a pre-construction visit to determine if there are any site access issues to be dealt with. From here, we move on to identifying any special requirements for caisson or foundation work, such as concrete delivery or de-watering. All of these things come into play for an elevated steel platform and we have the experience to manage them correctly.

In order for a rooftop platform to be correctly fabricated, we feel that a pre-construction site visit is critical to success…so much so that we won’t complete one without it. What this allows us to do is perform a Ground Penetrating Radar test or GPR test on the roof deck. This will help us to determine the exact column locations so that load-bearing attachments are correct. It also allows us to avoid conflicting with pre or post-tension cables which are also critical to success. Also, we review what stealth construction is needed to meet client and jurisdictional requirements. From here, our in-house fabrication team takes over and builds the platform to meet the specific needs of our client.

Tower Modifications Tower modifications new technology, new opportunity

Monopoles, Self-Support Structures, and Guyed Towers basically accomplish the same task…they support network infrastructure that enables mobile users access to voice and data services and applications. Tower Modifications can be a great way to extend the life of these structures, and can also be an opportunity to increase revenue. But you will need to keep existing carriers on-air throughout the process…and this is not easy, but our experience can help you get this done.

Monopole modifications can be far-ranging, from top to bottom. Whether it requires drilling into an existing caisson so that anchor bolts can be reinforced or adding transition stiffeners so that additional antennas can be mounted on the structure, one thing remains constant…the requirement not to disrupt the service of existing clients is paramount. This can be a difficult task as often the required modifications are located exactly where an existing carrier has their equipment mounted. We accomplish this feat with precise rigging and complete a process that is referred to as “floating the mount”. Because of our extensive experience, we can perform almost all modifications without disconnecting carriers, just ask us and we can show you how.

Self-Support tower upgrades can include many different scenarios and can bring with them different challenges that must be managed. Let’s first look at replacing the existing steel. Often the angle is replaced with larger angle and you better know which angle to remove and when, or the integrity of the structure is at risk. All modifications that we do are analyzed by in house engineering to determine if temporary bracing is required. This insures a safe and sound upgrade. Flange jump plates and split pipe are also used when modifying a tower, and in these scenarios welding is often the best way to attach the new steel to the existing. Welding at 200’ in the air brings fire prevention to a whole new level, and fire suppression is critical. That is why we bring our mobile fire suppression systems to every weld site we do.

Of the different types of structures that support wireless infrastructure, Guyed Towers can reach furthest into the sky and thus, provide the broadest coverage available. It is this quality that makes them ideal for carriers seeking to expand coverage into rural areas. But when they reach their structural limit the modifications quite often involve the guy wires themselves. When working with guy wires, experience and the proper equipment play a vital role in making sure the plumb and tensioning meet exacting specifications. Experience is also important if the modification requires the replacement of anchor points and anchor heads. Remember all this work is being performed to an existing tower that has existing clients located on the structure, so careful planning is critical. We have the tools and experience necessary to get the job completed as scheduled.

Special Projects We make sites work for you

Explosive growth in the wireless industry has driven the number of cell towers to increase from 900 in 1985 to over 205,000 in 2015. Many of these sites are new, but a large number of them are aging and in need of repair or replacement. Not all structures are alike, and many can be difficult to design a solution around. Special projects are what we call these opportunities, and we can help by modifying them to fit client needs without the high cost of replacements.

Concrete Monopole

When concrete monopoles fail to meet structural requirements, the usual thought process is to replace the pole, not upgrade it. This is the most expensive option and also the one most chosen…but there is another way to solve this problem. Our in-house engineers have designed a solution that enables the same principles used to modify steel structures to be applied to concrete monopoles. What we do ultimately creates a steel cage that clamps to the existing pole, and places steel plates in exactly the right locations. This customized solution provides a significant structural upgrade, and delivers significant savings over replacing the structure. If you have a challenge, perhaps we can help you.

Metalizing

The most common process for protecting steel in our industry is hot-dip galvanizing. This process basically immerses steel into a bath of molten zinc to produce a corrosive resistant coating. But as steel ages, so does the protective coating and this can lead to structural failure. But our team can help. We have the tools and the training to re-apply zinc to steel structures and we can complete this process in the field, where the structures are. We can process platforms, exposed beams, and many more structures without having to ship the pieces back to the factory. This process is better than painting and not only improves the aesthetics of the steel; it prolongs the life of the structure.