Fibre Composite Pile System
FUTUREpile® is believed to be Australia’s first fibre composite piling system for the reinstatment and rehabilitation of current foundations and the construction of new infrastructure.
Fibre reinforced plastics, or Fibre Composites (FC), have many advantageous properties over traditional materials that include high strength/stiffness to weight ratios, low weight and relatively good impact performance, whilst being resistant to corrosion, water, pests and UV deterioration.
Correctly designed and manufactured FC products, such as FuturePile, are designed for a service life of 75 years and require minimal maintenance during this period.
FuturePile is a cylindrical pipe pile designed to be a direct replacement for traditional piling materials and techniques, and can be incorporated into pile repair activities with minimal disruption to the usage of the bridge or jetty/pier asset.
Current pile sizes are 300, 475 and 600mm however the flexibility of BAC Technologies Pty Ltd’s (BAC) manufacturing process allows for standard sizes, or for the diameter and wall thickness of the piles to be tailored for each application to ensure optimisation of the materials and maximum cost effectiveness.
This size range suits applications ranging from repairing existing timber marine piles in piers/jetties up to the construction of new road bridge infrastructure.
Research and Development Process
The research and development process for the FuturePile product range was initiated following a request from the Brisbane City Council (BCC) to develop a method of rehabilitating the substructure of the heritage-listed Shorncliffe Pier, without closing the Pier or removing or modifying any headstock and/or deck.
Following the prototype development and acceptance of the concept, BAC designed and manufactured over 40 FuturePile® FC piles for the project and provided technical assistance in the design of the installation process.
Due to the success of the project, BAC patented the concept and began a Queensland Department of Employment, Economic Development and Innovation (DEEDI) Proof of Concept research program to further investigate and develop civil applications of the system.
The research and development process that followed involved:
Material coupon testing to gather mechanical properties for engineering
Traditional engineering preliminary structural design
FEA modelling and simulation
Prototyping of new manufacturing process
Manufacture of full 10m pile
Laboratory testing of compressive and moment serviceability
Pile driving testing
Pile driving analysis
FuturePile Structural Performance
Following the extensive development process the following parameters for the FuturePile® FC piles were determined and confirmed.
A 1m section of the 475 FuturePile was tested in compression up to a serviceability load of 1500kN and showed no sign of damage. The testing was halted at this point as the capacity of the test equipment was reached. The capacities of the current size range are tabulated below. In some applications with high moment requirements, it is possible to post-fill the composite section with concrete or other filler materials. This will result in a pile with the same or greater moment capacity as a current pile whilst remaining a light weight FC pile for the majority of the installation process.
H-Connector Pile Replacement
As a part of the system, BAC has designed, engineered and patented a method of pile replacement that allows the deteriorated upper portion of a pile in an existing bridge or pier to be replaced with a FC section, without the need to remove or modify the bridge superstructure.
With traditional piling materials the above-ground portion is susceptible to damage, attack from vermin, weathering and deterioration, which could lead to the foundation being unserviceable, however often the lower portion of the pile remains in good condition.
The FuturePile H-Connector method allows the upper portion of a pile to be replaced by a fully structurally capable FC pile section with minimal effort.
The process involves:
Identifying the serviceable section of the existing pile and removing the upper portion
Locating a FC H-Connector on the pile stump
Inserting the FC FuturePile section into the H-Connector
Jacking the pile to the underside of the headstock
Injection of epoxy grout or other fasteners to complete the installation.
The reduction of site work associated with the process greatly increases the cost effectiveness of pile rehabilitation.
Utilising the ability to have each pile custom fabricated to suit a particular application allows for much reduced installation costs and therefore lower life cycle costs.
Pile Jacket Reinstatement
In certain cases where there is only localised damage/deterioration to a pile it is preferable to have a method of pile strengthening that can reinstate the full capacity of the pile without removing the damaged section.
BAC has developed a pile jacketing technique where the full load carrying capacity of the pile can be reinstated through the use of FC pile jackets.
This method requires no jacking of the structure and does not involve load, vehicular or pedestrian restrictions during installation.
Each section of the FC jacket weighed approximately 23kg for a 3-metre length. The design is certified to AS5100 and the installation was completed in approximately three days with no lifting or other equipment required other than basic hand tools.