CCL provide the complete
design for a post-tensioned solution. CCL’s design team has the experience and
the expertise, gained by working on projects around the world, to provide you
with a prompt and effective design solution.
We utilise state-of-the-art design programs that are continuously updated to
reflect the latest international construction codes of practice.
CCL specialists are available to help structural engineers determine the best
option from an early design stage, through extensive value engineering in order
to meet specific requirements for each project. CCL can provide a detailed
scheme with sufficient information for tender purposes. Upon execution, CCL’s specialised
design team will develop the design and provide shop drawings for construction.
Post-tensioning tendons are
virtually replaced in the slab by the set of forces they exert on it:
compression along the slab perimeter, upward forces in the field and downward
forces over the supports.
Several elastic methods of
analysis can be used to determine stresses in slabs under gravity loads and
equivalent post-tensioning actions such as the Equivalent Frame Method (EFM)
and the Finite Element Method (FEM). Stresses and deflections resulting from
the elastic analysis are checked under Service Limit State (SLS) against
allowable values imposed by the adopted code of practice.
      
Critical sections are checked under Ultimate Limit State (ULS) and where a
lack of resistance occurs; it is compensated by localised additional ordinary
reinforcement. The punching shear is checked and if the corresponding
resistance is not sufficient, it is catered for by additional reinforcement,
shear studs or increased concrete thickness (drop caps).
When an analysis is satisfactorily completed, structural detailing is carried
out to show the slab’s layout and dimensions, tendons’ distribution and
profiles, details of ordinary reinforcement, jacking forces and corresponding
elongations in tendons due to stressing.
  
2 Way Banded 1 Way Banded 2 Way Distributed 1 Way Distributed
The CCL post-tensioned slab
systems can be integrated into any type of slab such as; flat slab, ribbed
slab, coffered slab or waffle slabs. The slab may include drop caps, drop
panels or band beams to produce optimal configurations. |
