At mac-group we understand the importance of sustainable soil management and are among one of the first contractors in Ireland to employ soil stabilisation method on our construction projects.
Outline of what the lime/cement stabilisation process is as follows;
- Excavation of material to a firm or stiff cohesive glacial till followed by 225mm layers of suitable fill material excavated from an onsite borrow pit.
- An integrated pulverising mixer with a hopper of lime passes over the layer of material and directly agitates and mixes the lime into the layer of material. The treated layer is then sealed with a roller.
- 24 hours later the material is tested to determine the moisture content of the previously treated material. Cement is then added to the material in the same method as the lime process. The treated layer is compacted again using a roller.
- 24 hours later CBR tests are carried out and the process can be repeated until the formation level is achieved to enable construction of foundations to commence.
Benefits
- One of the major benefits of soil stabilisation is the direct contribution it can bring to reducing Scope 3 Greenhouse Gas emissions. Scope 3 Greenhouse Gas emissions allows for all indirect emissions produced as a consequence of mac-group projects.
- Diverting made ground away from landfill , less lorry movements which would be needed to transport that amount of soil and stone to a nearby landfill. This has huge benefits for the local community as it reduces emissions, reduces congestion on the roads and reduces costs. Reducing vehicle movements also has a positive effect on the projects Scope 3 fuel emissions.
- Traditional ‘dig and dump’ techniques incurs the costs of vehicle movements and landfill tax. It also reduces importing virgin aggregates therefore reducing mac-groups dependency on the planet’s natural resources.
- There are significant time saving advantages by minimising the site preparation time and reducing tipping and importing. This has a knock-on effect of reducing the potential to contribute to negative air pollution by decreasing the risk of imported material dust pollution and vehicles driving over haul roads. This decreased the projects need to utilise dampening down of haul roads and materials and effectively eliminates the need for stockpile management and material storage on site.
Example of Benefits on one of our sites
If the traditional method had been used, 10,730 m3 of soil would have been disposed off. This would have required 1,073 lorry movements covering 30,795km. This example demonstrates the reduction in waste and transport when using the soil stabilisation method.
