Post Tensioning/Concrete Strength | Structural Technologies

What You Need to Know About Post-Tensioning and Concrete Strength

Concrete is the most widely used construction material worldwide thanks to its durability, strength, and cost-effectiveness. Reinforced concrete is the most common type of concrete used for buildings, and post-tensioning is one option for steel reinforcement.

What Is Post-Tensioning for Buildings?

Post-tensioning is an approach to building concrete strength for structures through prestressing.

During the process, experts reduce tensile stresses by introducing compressive stresses first. This method applies tension to the tendons after the concrete has hardened and transfers the prestressing force to the material through end anchorages.

How Post-Tensioning Affects Concrete Strength

A post-tensioning system includes high-tensile cables that industry professionals call tendons. Each tendon consists of multiple braided steel wires threaded through a plastic tube. Installers place the tubes containing the tendons within the concrete formwork, ensuring the ends are flush to prevent concrete from entering the lines.

The concrete then cures before strength measurement occurs. Accurate strength testing is crucial to support project success — concrete that’s too weak is prone to collapse during stressing, while material that’s too strong is vulnerable to cracking.

Concrete that meets the required strength standards is ready to stress. Installers begin stretching the tendons to a specified value using hydraulic jacks. Once they reach the required tension, they anchor the tendons to the concrete’s edges.

The stressing process imparts compressive strength to the slab while helping balance the load so that the concrete no longer experiences its own weight. As a result, the post-tension structure offers increased load-bearing capacity.

The Benefits of Post-Tensioning and Concrete Strength

Post-tensioning provides numerous construction benefits, including:

  • Higher-quality results: This method supports more accurate concrete placement, enhances stability and increases concrete strength for higher-quality end projects.
  • On-site convenience: While pre-tensioning must take place in a facility, post-tensioning occurs on the job site after pouring the concrete, making it a much more convenient process.
  • Economic savings: Post-tensioning is more affordable when compared to traditional reinforcement methods because it requires lower quantities of concrete and steel.
  • Design flexibility: Because post-tensioning allows for longer and thinner spans, designers enjoy more layout flexibility. The technique can also be used in existing concrete repairs.
  • Faster project completion: Post-tensioning needs less steel placement and supports removing formwork sooner for significant time savings.
  • Sustainability: This approach saves resources and lowers energy consumption to support greener construction practices.
  • Less sagging and vibration: The load-balancing aspects of post-tensioning produce less deflection and vibration.
  • Foundational versatility: Post-tensioning works with various foundation styles, including caisson, mat and more.


At STRUCTURAL TECHNOLOGIES, we focus on strengthening structures and extending their life spans. Our team boasts decades of collective expertise across the built environment to provide end-to-end project support. We’re a single solution for every process step, from development to delivery.

Professional post-tensioning services and high-quality products are the cornerstones of project success. Learn more about our post-tensioning capabilities by contacting a team member online.