External post-tensioning
Active strengthening technique for performance upgrade
The primary reasons for the strengthening of concrete structures are typically to increase existing elements’ capacity to carry new loads or to resolve an existing deficiency. Made widely known by a PTI legend, Kenneth Bondy, external post-tensioning involves the introduction of external forces to the structural elements that would offset part or all of the effects of external loads. Following Ken Bondy's method, we have extensive experience in design and installation of the external post-tensioning system to improve strength and serviceability of buildings.
Application #1: Roof Beam Strengthening
At the Iniala Beach Hotel in Phang-Nga, the roof beams are to carry an additional load from large bathtubs. Because of limited space beneath the floor, the EPT technique was successfully used to strengthen the roof beam. EPT is considered weightless and doesn't disturb any function of the building to the floor below.
This successful project reveals the potential of EPT in minimizing construction cost and time while staying within architectural requirements.
Application #2: Slab Strengthening with EPT and Shear Collar
In our pioneering project, we applied External Prestressing Technique (EPT) to strengthen 3,000 m² of a post-tensioned slab at Monthathip Hall, Udonthani, enabling it to carry an additional 5 kN/m² live load.
This is both the first application and the largest strengthened area using EPT in Thailand.
By adopting EPT, we achieved significant savings in construction cost and time compared with conventional steel beam strengthening.
