Post Tensioning System Installation

Torque Tensioning

The high quality rolled thread of Williams All-Thread-Bar can be torque tensioned up to 60% of the bar's ultimate strength. This eliminates the costly and time-consuming process of lifting heavy jacking equipment on and off with a crane. The entire process takes only minutes by workers already in place and relieves expensive crane equipment to be utilized elsewhere on the project. This process alone can speed up the installation process and save the installer valuable and expensive time. A torque tension graph is provided below.

Tensioning By Jacking

Tensioning by jacking can be accomplished with the various tensioning jacks shown on page 15. Williams post tensioning jacks are designed for flush or recessed situations. Jacks are matched with hand pumps and electric or air motors. Jacks may be purchased or rented as required. Rental equipment packages include jack ram, hoses, gauges, power unit and wrenches for transferring the load from the jack to the nut and plate. Torque Tensioning charts for the 150 KSI All-Thread-Bar can be found here.

Grouting

Grouting equipment shall be capable of properly mixing a water and Portland cement mix having a water-cement ratio of 0.46 (5 gallons water for a 94-lb. sack of cement). Equipment shall be capable of pumping at pressures up to 200 PSI. Standby equipment for flushing must be available. Grouting procedures should always assure duct is grouted from the lowest gravitational point and vented to the highest.

Grouting equipment shown on page 14 is available for sale or rental from Williams. Williams Wil-X-Cement Grout is recommended for use in Williams grouting equipment. Wil-X-Cement Grout meets all requirements of ASTM C-845.