Bonded Post-Tensioning

Prestressed concrete has been around for years, and it serves as a more efficient, and reliable alternative to reinforced concrete. Prestressed concrete, as we know it, can be divided into 2 separate technologies, both offer significant material savings: pre-tensioned and post-tensioned concrete. Both technologies are commonly used in structural applications, however pre-tensioned concrete is usually precast at manufacturer’s plant and delivered to the building site, and post-tensioned concrete is cast on site.

SDS specializes in the design of post-tensioned concrete members therefore we will focus on this technological solution going forward.

Using post-tensioned systems, we introduce additional internal forces into the structural member. Those forces (bending moment and compression throughout the member) balance or counteract the effects of applied loading. The cables are stressed after the concrete has dried and gained sufficient compressive strength.

This beneficial effect results in better overall performance of the structure and extends the time between necessary maintenance works.

Tendons (Cables) are stressed after concrete has reached sufficient compressive strength. Cable ducts with prestressing steel inside are later filled with cementitious grout, therefore steel is bonded to the concrete element. Strands are delivered in bundles and separately from ducts, which are laid out and cut into desired length at the building site.

SDS specializes in both unbonded and bonded technologies, therefore we could advise you on selecting the structural solution most beneficial to your project

• Rebar and cable ducts are laid out.

• Strands are later pushed into cable ducts, and cut   

• Concrete is poured

• Cables are stressed and cut

• Cables are filled with cementitious grout