Dubai Wharf – PTI Trial
The Problem
Dubai Wharf Properties.
Dubai Wharf is a mixed-use waterfront development in Dubai with post-tensioned concrete construction. A trial was undertaken on two selected post-tension tendons within the B2 slab to address corrosion risk associated with moisture ingress and deterioration within the tendon system.
Post-tensioned tendons can be particularly vulnerable where defects in the grout, sheathing or tendon anchorage allow moisture to reach the prestressing steel. The documented tendon conditions showed signs of corrosion-related deterioration, creating the need for a targeted treatment capable of reaching the internal tendon environment.
The work also had to be completed within an active basement environment with several site-specific hazards, including drilling operations, electrical equipment, dust exposure, sharp objects, slip and trip hazards, and work-at-height considerations. These conditions required careful planning and safety controls throughout the trial.
The Solution
Vector Corrosion developed and implemented a controlled Post Tension Impregnation (PTI) trial on two selected tendons. The process was designed to introduce Post-Tech® PTI impregnation material into the tendon system under pressure to mitigate corrosion risk and improve tendon durability.
The trial included:
Ground Penetrating Radar (GPR) to locate tendon ends and intermediate points
Impact Echo/Pulse Velocity (IE/PV) testing to assess the internal tendons and identify potential grout voids or defects
Borescope inspection of accessible tendon locations to visually assess internal tendon and grout conditions
Drilling 6 to 8 mm access holes through the concrete cover and tendon sheathing
Installation of impregnation ports
Compressed air testing to verify a continuous flow path through the tendon and identify leakage points prior to impregnation
Sealing identified leakage points with 100% solids epoxy paste to contain the impregnation material within the tendon system
Pressure application of Post-Tech® PTI impregnation material
Maintaining the required pressure during the impregnation process
Removal and permanent sealing of access ports following treatment
Quality control inspections covering port installation, air testing, material application and final sealing
Given the active basement environment and hazards associated with the work, Vector Corrosion incorporated appropriate safety precautions and controls throughout mobilisation, tendon location, drilling, impregnation and site cleaning activities. This allowed the specialist work to be carried out in a controlled manner while managing the risks associated with the surrounding work environment.
Using GPR to locate tendon ends and intermediate points.
Using IE/PV testing to assess the internal tendons and identify potential grout voids or defects.
Exposed post-tensioned tendon.
Performing a borescope inspection to visually assess internal tendon and grout conditions.
The Result
The PTI pilot trial established a controlled and repeatable procedure for investigating and treating the selected post-tensioned tendons. The combination of GPR, IE/PV and borescope inspection provided multiple methods for locating and assessing the tendon system prior to carrying out the impregnation treatment.
The completed trial demonstrated a practical method for introducing corrosion mitigation material into the tendon system and established the testing, installation and quality control procedures required for implementation.
Through careful planning and appropriate safety controls, the specialised post-tension investigation and treatment works were completed safely within the challenging basement environment. The trial provided the project team with a documented basis for evaluating Post Tension Impregnation as a corrosion mitigation approach for post-tensioned tendons at Dubai Wharf.
Air testing to identify leakage points before impregnation.
Pressure application of Post-Tech® PTI impregnation material.