A post-tensioned cement clinker silo for the Ash Grove Cement Company in Chanute, Kansas was part of an overall expansion of the facility to address the increasing demand for cement in the United States.

With a diameter of 125 feet and a height of 150 feet, the size of the silo is considerable. Post-tensioning was chosen as the primary hoop reinforcement for several reasons. Due to the nature of slip form construction, manpower requirements are enormous for a relatively short duration of time. Therefore, reducing the amount of mild reinforcement contributes to maximizing the slip rate and minimizing the manpower requirements. The post-tensioning is then placed off the critical path of the slip. Additionally, reducing the amount of mild reinforcement congestion allows for higher-quality concrete placement and more accurate placement of the mild reinforcement and post-tensioning ducts.

VSL's scope of work included optimizing the tendon sizes and spacings, furnishing the post-tensioning system, pushing the strands into the ducts, and stressing and injection grouting of the tendons. VSL provided full-time observation during the slip operation to insure proper placement of the anchorages and ducts.

VSL's leadership in the planning process of the post-tensioning operations, and highly-skilled field crew, contributed substantially to the overall success of the project.