Commercial Post-Tensioning
Tendon Systems delivers quality, service and value nationwide, specializing in cast-in-place post-tensioned concrete structures.
This includes high rise, multi-family, parking garages, hotels, offices and condominiums. Supported with in-house engineering design support, Tendon Systems can provide its Clients responsive design and budgeting input at an early stage of project development.
Tendon Systems’ Unbonded Monostrand System utilizes the latest extrusion technology to produce unbonded tendons with a uniform coating of abrasion resistant, high density polyethylene sheathing over a low friction, corrosion inhibiting lubricant. All unbonded post tension tendons are fabricated according to the governing ASTM and PTI Standards in our PTI Certified Plant.
Fabricated tendons are tagged, bundled and delivered by construction sequence for ease of field placement.
Tendon Systems’ encapsulated system is designed for aggressive corrosive environments such as coastal areas and parking garages exposed to de-icing salts. The encapsulated system comprises plastic coated anchorages, 60 mil plastic sheathing and positive locking connection tubes and end caps ensuring complete isolation of the wedge cavity and strand from corrosive elements.
Stressing Equipment is serviced and calibrated prior to delivery to the jobsite. Technical Field Service Representatives provide our Clients with on-site assistance for Tendon Systems installation, stressing and construction sequencing.
For turn-key packages, Tendon system offers a cost effective labor force to provide complete installation services for all post-tensioning, ShearailsTM and rebar materials.
MULTISTRAND & SPECIALTY SYSTEMS
Tendon Systems provides Post-Tensioning stressbar solutions for unique construction and geotechnical applications, bonded multistrand Post-Tensioning systems and steel fabrications for specialized uses.
Stressbar systems include ground anchor applications and tiedowns. Tiedown applications can include sea walls. Laboratory floors for wind and seismic testing have utilized stressbar systems so new structural technologies can be analyzed.
Tendon Systems offers Bonded Post-Tensioning Systems for Health Care structures where Owners require future flexibility for structural modifications, coring through slabs and adding openings as conditions change. Bonded Post-Tensioning also meets the latest Department of Defense criteria for blast mitigation and makes an excellent solution for transfer girders, wind farm structures, bridges and aerial structures.
SHEARAIL™ – SHEAR STUD REINFORCEMENT
Shearail™ by Tendon Systems, LLC is ICC ( International Code Council) strength tested. Shearail™ shear stud reinforcement system is an advanced, engineered product.
Shearail™ provides significant building construction cost savings since drop panels and concrete shear capitals can be eliminated. This yields formwork and concrete savings and enables a faster construction schedule.
Stud shear reinforcement has emerged as the preferred method of increasing punching capacity in thin slabs. It has been used in thousands of buildings all over the world, including the United States and Canada. Sherails™ provide an uncongested and quickly installed alternative to closed stirrups or other less popular methods of punching strengthening. Post-tensioning or other slab reinforcement can simply be installed between the heads of the vertical studs.
Reduced installation time translates into reduced labor costs and faster turnaround time per pour. With the use of the design guidelines of ACI 421.1R99, Shearails™ can eliminate the need for shear capitals, significantly reducing formwork costs and allowing the use of fly forms. The large 10:1 head-to-stem cross-sectional area ratio provides superior anchorage, allowing full utilization of the stud material.
Why Shearails™? Punching Shear is a significant design consideration in flat plate slabs. Often it is the controlling design criterion.
Public Life Safety Enhanced! Structural failures due to inadequate moment capacity usually exhibit advanced warning signs such as excessive slab deflections and concrete cracking. These warning indicators provide notice and the structure can be evacuated, shored and stabilized so public safety can be secured. Punching shear capacity failures, however, are abrupt and usually catastrophic and can lead to a progressive failure collapse and severe loss of life.
What are the Design Team’s Options to high punching shear?
- Shear capitals, drop heads or drop panels, or
- Thicker slab depths, or
- Larger column size, or
- Closed rebar stirrup reinforcement, or
- Headed stud shear reinforcement ShearailsTM
Shear capitals, drop heads or drop panels are an effective solution, but compound the complexity of the formwork process, resulting in higher formwork expenditures when compared to a flat plate formed slab. Furthermore, the aesthetics of a drop capital on an exposed ceiling for condominiums, apartments and hotels usually preclude their use for these applications. Thicker slabs can work from a structural capacity standpoint, but this requires more concrete which increases concrete forming costs, column sizes, rebar and foundation requirements.
Larger column sizes would be an effective structural solution, but the additional size presents the Architect with larger columns that would encroach into adjacent rooms.
Closed rebar stirrup reinforcement has traditionally been used to increase the punching strength of flat plates but in slabs thinner than 10 inches it is difficult to achieve anchorage of the stirrups. The full capacity of a closed rebar stirrup cannot be achieved in thin slabs as a result of slippage at the stirrup bends. As a recognition of this limitation ACI-318-02 Building Code prohibited the use of rebar stirrups in thin slabs and has added additional detailing requirements in thicker slabs that make placement of rebar stirrups impractical due to the congestion created.
SOLUTION…Shearail™ Brand Shear Stud Reinforcement and eliminate those problems and costs!
Structures in areas of high seismic risk, moment reversals and high unbalanced joint moments can undergo premature punching failure. Shearails™ can improve the lateral drift capacity of a column-slab joint by absorbing energy with their ductility and superior anchorage.
Shearails™ are manufactured under strict quality control ICC manufacturing and testing certification program. With accurate field placement drawings prepared by Tendon System’s experienced engineering and drafting staff showing exact rail locations, the simplicity of SHEARAIL™ installation is unsurpassed.
INSTALLATION
- Clip the provided chair to the rail. Place one chair in from each end of the rail and additional chairs on the rail as required.
- Position rails on formwork at the corner of every column but not closer than 2 in. from the slab edge or opening. Rails should be equally spaced along column face. (see Figure 1.1)
- Nail the chair to the formwork to ensure correct position is maintained during concrete installation. Rails should always be installed with the studs vertical.
PRODUCT SPECIFICATION
ShearailTM Studs meet or exceed all of the following requirements.
- Yield Strength: 51,000 psi (350 MPa), minimum
- Tensile Strength: 65,000 psi (450 MPa), minimum
- Elongation: 20 percent in 2 inches (51mm), minimum
- Reduction of Area: 50 percent, minimum
ShearailTM Rails meet or exceed all of the following requirements.
- Yield Strength: 44,000 psi (300 MPa), minimum
- Tensile Strength: 65,000 psi (450 MPa), minimum
- Elongation: 20 percent in 8 inches (203mm), minimum
- Reduction of Area: 50 percent, minimum
