One of the main uses for end of life tyres is to process them into tyre bales. These bales are made of approximately 100 tyres which have been processed through a hydraulic press to form a block, which is around 1.2m x 1.2m x 0.8m, weighing around 800kgs.
Once compressed these blocks are secured with four steel wires of at least 3.8mm in diameter, fixed using the looping method, which gives structural integrity to the bale, allowing it to be picked up, moved and stacked vertically by a fork lift truck, without the need for pallets. The end result of our work is a product which is 100% recycled.
The tyre bales produced by Tirec Ltd have many applications within the construction industry and the leisure sector in the UK.
At present Tirec produces standard ‘reference’ bales. If however, an end user requires specialist sized bales made to the specification for bales contained within the PAS 108 document, these can be produced upon request.
The use of tyre bales in construction is progressively becoming the norm due to the industry’s increasing awareness of their benefits, with help over recent years from WRAP, H R Wallingford, The Transport Research Laboratory and Southampton University among others.
Anyone interested in a current example of the use of tyre bales in road construction is recommended to read about the Bedford bypass. A requirement of this key part of the A421, the East-West link corridor between Cambridge and Oxford, was to construct an embankment over ground with poor load bearing capacity.
This is the first time tyre bales, in this case using over 32,000 tyres that otherwise would have been shredded or burnt, have been used to form an embankment on a public road in the UK.
Search – Bedford bypass tyre bales, then newcivilengineer.com for further reading.
Advantages of using Tyre bales for construction and civil engineering projects:
- Low cost
- High load
- Uniform size
- Soil Elevation
- Lighter weight
- Great drainage
Case Studies and Construction Examples
The case studies presented below cover a wide range of applications including roads over soft ground, slope repairs, retaining walls and river and flood protection works. These applications exploit the key characteristics of tyre bales such as their lightweight, their high porosity and permeability, the fact that they are relatively inert, their ease of handling and their versatility.
It is clear that the manufacture of tyre bales and their subsequent use in construction is a highly effective and beneficial use of end of use tyres and has considerable potential for the future.
Flood defence project, River Witham, UK
12,000 tyre bales were used for this project The project involved strengthening and refurbishing of the flood defence embankments between Lincoln and Boston in Lincolnshire. The project took 4 months and serviced around 1.5km of the river embankment during the winter months, something that would not have been possible using conventional clay materials.
Landfill drainage layer project, Powys, Wales, UK
Example of a landfill drainage layer project where tyre bales are known as Used Tyre Derived Aggregate Replacement (UTDAR). Potters Waste Management, at their Bryn Posteg landfill site in Wales, use baled tyres as an UTDAR for the base of their landfill site.
Dam wall project, Worcestershire, UK
Tyre bales were substituted for traditional stone and clay materials.
Construction of Road Foundations on Soft Ground
Lightweight Road Embankment Over Peat, Helmsdale, Scotland, UK
In the Highlands of Scotland many roads are lightly trafficked and serve small, scattered communities. However they may be the only routes connecting the communities with the outside world and their importance is thus greater than the traffic levels alone would suggest. Many of these roads are constructed across areas of peat, with a weak, highly compressible nature leading to a unique set of engineering problems. The use of normal construction materials (bituminous and unbound) often leads to large differential settlements due to the variability of the peat thickness and stiffness. This leads to steps or tilting in the surface, a hazard to road traffic. The use of lightweight materials, such as expanded polystyrene (EPS) to minimize these effects, is usually uneconomic due to the high cost of the materials.
Road Construction Over Soft Ground, Chautauqua County, New York State, USA
The Chautauqua County Department of Public Facilities have led a total of five projects involving the use of lightweight tyre bales as a subgrade replacement for roads over soft ground. The tyre bales resulting from the clean up of the Levant tyre dump and from the ongoing tyre amnesty programme were used in these projects.
Road Over Soft Ground in Woodland, , UK
A long section of an un-surfaced road through an area of soft ground in woodland had developed deep ruts as a result of use by four-wheel drive vehicles and motorcycles. Normally this would have been repaired by excavating the rutted area and replacing the soil with free draining granular material, in the form of capping and unbound sub-base. As an alternative, the excavated soil was replaced by tyre bales, with a 150mm layer of crushed natural stone to form the road surface. This resulted in significant cost savings as well as avoiding the use of natural aggregate.
Access Road over Soft Ground, Nether Dallachy Landfill Site, Fochabers, Moray, UK
The landfill is located at a former sand and gravel quarry near the Moray Firth. The site is typically 5m to 5.5m above Ordnance Datum and low lying parts of the site are subject to flooding in the winter due to seasonal variation in the ground water level. An extension to the existing haul road was required to service a new landfill cell. The surface of the existing haul road is 6.15m above Ordnance Datum (AOD), up to 1.5m of upfill (average 1.0m) was required to ensure the new road was not subjected to winter flooding.
Slope Failure Repair, Interstate Highway 30, Tarrant County, Texas, USA
The remediation of soil cut slope instability in Tarrant County, Texas has conventionally been achieved using existing or imported soils, with or without modification by hydraulic binders and often in conjunction with an ‘H’-beam wall, in order to minimise costs and construction time. More recently consideration has been given to the use of tyre blocks as a partial replacement for soil fill. This approach is considered likely to significantly improve the subsequent long-term stability of the repair, while also providing the benefit of reusing waste tyres. This is especially significant where the in-situ soils comprise high plasticity clays, which may be marginally suitable for such applications, highly moisture sensitive and inherently unstable. Surface or groundwater seepage also may be a contributing factor to slope instability as this region frequently experiences high intensity storms.
Example of reed bed project
Various ponds for reed bed drainage projects are being built throughout the UK using the blocks as the first line of drainage down to a secondary high-tec SUDS system to reduce foul water to clean.
Picture courtesy of Northern Tyre Recycling Ltd
- In addition to their use in construction and leisure, Tirec Ltd also sell tyre bales for use as tyre derived fuel. These tyre bales have the benefit that when burnt in industrial furnaces, both in the UK, and through export in containers, by customers in India, Bangladesh and other countries, they have a higher calorific value than coal.
They also have the green benefit that when used in coal power plants and cement works, they are an effective substitution for primary fossil fuels, and they show a large number of ecological advantages over the use of fossil fuels.
For more information please read more about Tyre Derived Fuel >>