We recently attended an exclusive lunch and learn event, hosted by William Daly from Helifix, to learn about their newest product. It was a great presentation that we all benefited from as it is a product that works as another underpinning solution for subsidence issues, so we wanted to share our learnings about the product with you.
What is the product?
Helifix Micro-Piles system provides structural support to a building’s foundations using a small pipe pile that is attached to the edge of a slab using a steel bracket. Helifix Micro-Piles were developed to provide property owners with a more cost-effective and a less disruptive alternative to mass concrete underpinning for structural issues caused by soil subsidence. Helifix Micro piles are ideal for structures that have limited space, restricted access or environmental concerns as opposed to conventional options for underpinning.
How do Helifix Micro piles work?
Helifix Micro Piles provide property owners with a cost-effective and a minimal disruptive solution for structural support to a building’s foundation damaged due to soil subsidence compared with other underpinning options. Soil subsidence can be caused by multiple factors including:
Shrinkable clay soils
As soil under a structure reduces due to loss of moisture, it can no longer provide support for the foundations and soil subsidence occurs and as a result, can cause structural issues over time. Moisture loss can occur due to dry weather and removal by vegetation in the area of the structure.
As a result of heavy rain or broken and leaking pipes, the soil underneath a building can be washed away, resulting in soil instability and possible structural issues requiring underpinning.
When an extension to an existing building is constructed, soil consolidation caused by the additional weight of the new structure can result in soil subsidence. Different types of soils across a site can lead to different rates of settlement which can also result in soil consolidation.
Every building has different loadings which can affect the foundations and cause structural issues. Concentrated loads are when a structure’s load is applied to a small area in the foundations, rather than over a larger area. Examples of concentrated loads could include roof loads, environmental factors such as wind or snow and internal renovations.
The effects of soil subsidence on a structure can be mitigated by using the Helifix Micro Piles System. Following a detailed assessment of each situation and other factors such as cost constraints and site considerations, engineers install Micro Piles to support the structure’s foundations. Micro Piles are installed by:
- Excavations are dug at the foundation locations of the Micro Piles which is determined before work commences. The amount and spacing of the Micro piles are determined by the soil quality and extent of the structural issues.
- A small recess for the Micro Piles top bracket is cut in the building’s slab to ensure that the slab is fully supported by the Micro Pile.
- The Micro Pile is installed by `screwing’ to a depth that provides stable soil, and a specified bearing capacity is achieved. Micro Piles are installed to be placed centrally to ensure loads are spread evenly on the Micro Piles. The Micro Pile’s bearing capacity is continually monitored as installation progresses and once capacity is reached, the pile is cut off approximately 250mm above the existing building’s slab.
- Adjustable support brackets are installed to the top of the screw pile and placed under the structure’s foundations.
- The brackets are lifted until the load of the structure is applied to the micro pile.
- Once the micro pile installation is complete, the excavation area is refilled fully concealing the Helifix Micro Pile.
To learn more, visit their website: https://www.helifix.com.au/