Barrier Cable Systems Offer High Performance at Lower Cost
Although the primary purpose of parking structures is to provide vehicle parking spaces, design considerations must address considerably more than the structural integrity required to handle anticipated loads. Provisions must be incorporated to ensure that vehicles enter and exit only at locations designed for such purposes. Pedestrian control is also an important consideration; structures must be designed to prevent pedestrians from falling and minimize the potential for pedestrian-vehicle interaction.
The most common means of addressing safety considerations is through use of solid crash walls or barrier cables, with the latter offering significant advantages. Compared to concrete walls, barrier cables are:
- More cost effective
- Lighter- approximately 6 pounds per foot compared to a minimum of 240 pounds per foot for a crash wall
- More design friendly- They allow greater exterior design flexibility than solid walls
Tendon Systems barrier cable systems are specifically designed to meet the International Building Code (IBC) vehicular impact and pedestrian fall prevention requirements. Compared to concrete crash walls, Tendon barrier cable systems enable dead load reduction of the structure and significant cost savings. Tendon barrier cable systems are also more environmentally friendly as they maximize natural ventilation and daylight while also consuming less energy during the construction process.
The cables used in barrier cable systems aren’t of the garden variety that can be found at your local Home Depot. Tendon Systems uses ASTM A416-compliant ½” in diameter 270 KSI (kilopound per square inch) 7-wire stranded cables with a galvanized coating. The most widely specified coating is Class A-ASTM A475 galvanization. Enhanced coatings include a zinc-aluminum alloy ASTM B750 Galfan which offers 3 to 1 corrosion performance improvement. For highly corrosive environments, enhanced protection is provided by the addition of 60-mil extruded high-density polyethylene (HDPE) sheathing, which is hot-melt extruded over wax coated cable. HDPE sheathing is available in a wide variety of colors, and special ultra-violet, anti-oxidizing inhibitors, added during the coating process, ensure optimum durability and weather resistance.
Irrespective of coating type, use of high-quality materials is essential to meeting building and performance requirements. The cables used in barrier systems are the same type as those used in post-tensioned concrete. And although they aren’t stressed to the same degree, (as in post tensioning) they are prestressed to assure optimum performance in resisting vehicle impact. Barrier cables prevent vehicles from making inappropriate exits from a parking structure by stretching to absorb kinetic energy. To qualify as a vehicle barrier, a cable system must handle the equivalent of a 6,000-pound static load and stop a vehicle within 18” of the point of impact.
Another advantage offered by Tendon barrier cable systems is lower repair costs in the event of an impact. Tensioned barrier cables typically spring back to their original position after impact, thereby avoiding the permanent deformation that other systems would incur. In the event of extreme impacts causing a cable to be broken or permanently deformed, replacement is considerably less expensive than rebuilding or replacing a crash wall.
Of course, proper design and construction are essential if a barrier cable system is to adequately meet performance requirements. Tendon Systems is a fully licensed and insured barrier cable supplier and installer, and has a full staff of in-house engineers licensed in 30 states, qualified detailers, and experienced project managers with proven expertise in barrier cable design and installation. During the past 30 years, our team has completed over 1,000 projects incorporating barrier cable systems and services for vehicular and pedestrian restraint and safety. Tendon’s proven means-and-methods provide the most dependable and cost-effective solutions to vehicle containment and pedestrian control challenges.
A seasoned management team, combined with a dedicated staff of experienced professionals, enables Tendon Systems to provide our clients with a reliable project partner that adds value from conception to completion.