Road Stabilisation And Dust Prevention
RoadBond binds the fine particles and increases compaction of the surface layer to prevent dust in roads, driveways, yards, construction sites and car parks. RoadBond is manufactured from a powerful natural organic binding agent. It is both a compaction aid and soil stabilisation agent which increases soil density and bearing strength while reducing voids and plasticity. It binds and compacts to create a hard, durable surface and prevent surface abrasion loss.
Benefits of using RoadBond
- Cost Effective
- Easy to apply, just add to water truck
- Environmentally safe
- Long lasting
- No additional machinery needed
- Wide range of applications, to compact and stabilise to prevent dust and erosion
- Dramatically reduces road maintenance
RoadBond is a liquid concentrate that mixes in water for ease of application. It is environmentally safe and is effective irrespective of soil type.
The Problems of Unsealed Roads
Many unsealed roads do not have the ideal range and distribution of particle sizes to give a good load bearing capacity when wet (coarser particles) or sufficient plastic capability (clay) when dry to prevent material from breaking loose. All gravel roads, when dry suffer some surface abrasion loss resulting in dust because, the adhesion between the particles is reduced.
Loose material on the road causes dust that blows away or washes away under heavy rain. Over time, the amount of fine binding soil in the road is reduced and gradually more and larger particles break away. The loose surface becomes prone to increased dust, pot holes and corrugation, making the road uncomfortable and dangerous to drive upon.
Ongoing maintenance is expensive, and in time the fines are lost and the road deteriorates faster requiring more regular maintenance.
THE ANSWER IS SIMPLE AND EASY TREAT THE ROAD WITH ROADBOND
RoadBond has a powerful binding action on soil particles. It combines with the aggregates and fines to create a hard, durable surface that resists surface abrasion and dusting. It increases compaction and density and reduces voids, reducing water penetration, and it reduces swell, shrinkage and plasticity thereby reducing the damaging effects of wetting and drying cycles.
RoadBond is made from two of the strongest natural binding agents; calcium and lignin. Lignin is a complex natural polymer extracted from paper pulp. Lignin is nature's binder, it binds the fibers in trees and plants. Calcium compounds have a binding action in soil (whereas sodium is dispersive), and the major chemical stabiliser used worldwide, e.g., cement, lime and calcium chloride is calcium based. RoadBond thus stabilises and binds the soil by combining the strong, effective binding actions of calcium and lignin.
RoadBond also acts as a compaction aid to increase compaction, it incorporates sulphonated hydrocarbons that have a high level of surface activity and imparts an electrical charge that induces ionic exchange in clays with high cation exchange capacity (the less stable clays). This modifies the clay, reducing it's electrostatic attraction to water, enabling greater particle realignment to increase compaction and stabilise the clay.
While it acts as an Ionic Soil Stabiliser, the principal stabilising action of RoadBond is through its powerful binding action, so that unlike ionic stabilisers, it still performs on soils that do not respond to ionic exchange agents. The fines and aggregates are bound together in roads treated with RoadBond. However, the bonds are not as rigid as cement bonds. Trees in which the fibers are bound by lignin will flex and return to their original shape whereas concrete is prone to cracking when flexing occurs. RoadBond treated roads therefore display the best characteristics of a bound pavement and a flexible pavement.
Roadbond is compatible with cement and lime stabilisation and effectively enhances their performance. Calcium lignosulphonate, on which Roadbond is based is used in the refractory, ceramics and concrete products industries to provide increased compaction and adhesion. Addition of Roadbond to increase compaction and binding improves cement and lime stabilisation and can reduce the amount of cement or lime required.
RoadBond is easy to apply simply adding to water at the required dosage rate. Standard machinery such as water truck, roller and grader is all that is required. Ideal results are achieved with stabilisation machines. For surface dust control only water spraying equipment is required.
Soil Types Suitable For Treatment With RoadBond
RoadBond can be used on all soil types but best results are achieved in soil with near to ideal Particle Size Distribution with 12 -15% clay, although RoadBond is effective in soils with much higher clay content. If soil is mainly silt or sand, lacking clay, and prone to corrugation, higher dosages are required to provide additional binding. RoadBond is effective irrespective of soil pH.
Roads treated with RoadBond will require minimal maintenance and are easily maintained when the following application procedure is followed:
- If dry, wet the surface
- Scarify and grade to break up lumps
- Blade loose aggregates into windrows at side
- Add RoadBond to water at dilution of 1 RoadBond: 2 water(Add 5 drums to 2000L) and spray evenly over the windrows and center with minimal overlap. Apply at 1.50L/sq.m. for each 50mm of depth treated
- Add water if necessary to bring to OMC for optimum compaction
- Blade and windrow to mix, then form crown with a slope of 40mm per meter
- Compact surface with vibrating roller then finish with multi-tire roller
When treated in the above manner, RoadBond will act as a dust control agent.
Note: Ensure that no untreated material is brought into the road surface while grading the crown and contouring the road, as any such material will not contain RoadBond soil binding agent. RoadBond solution will need to be added to any untreated material brought onto the road surface.
Note: Increase the concentration of RoadBond in Sandy/Silty soils lacking clay. Clay is the binding soil within a typical road gravel, and extra RoadBond is needed to provide additional binding in the soil matrix if there is insufficient clay.
It is normally sufficient to treat only the top 50mm of roadbase with RoadBond if the roadbase, subbase and subgrade are reasonably stable with acceptable bearing capacity. If however the base courses are unstable with poor bearing capacity it is advisable to treat to a depth of 150mm with an Ionic Soil Stabiliser such as RoadPacker Plus, and treat the top 50mm with RoadBond to bind the surface.
Short Term Dust Control
The concentration at which RoadBond is applied will determine how long it is effective as a surface dust preventive treatment. For effective dust control for up to 30 days the following procedure should be followed:
- If dry, water the surface
- If surface compacted and hard, lightly grade the surface to increase penetration
- If soil has > 12% clay dilute 12 parts water to 1 part RoadBond (5% solids) i.e. 1 x 200L drum in 2400L water and apply at minimum rate of 1.25 liters per sq.m. One drum can treat up to 2080sq.m
Note: If there is some depth of loose material on the surface, increase application rate to ensure RoadBond solution penetrates all loose material In soils with < 15% clay increase concentration of RoadBond. Suggest dosage rates: 8 - 12% clay - 10 water: 1 RoadBond 5 - 8% clay - 8 water: 1 RoadBond 5 % clay 5 water: 1 RoadBond
Maintenance of Roadbond Treated Roads
RoadBond stabilised roads will remain maintenance free for a minimum of 12 months and in many instances much longer. All unsealed roads however, will suffer some surface abrasion loss which contributes to dust. The surface of roads containing < 12% clay will normally break up and dust faster because binding soil is lacking.
If 'Short Term Dust Control' treatment has been applied simply reapply. Re-Application increases concentration of RoadBond in the soil and therefore the effective dust control.
RoadBond stabilised roads are easily maintained if the surface deteriorates over time. Occasional re-sprays, e.g. annually are advised. To retreat RoadBond stabilised roads' spray the surface with a solution of 1 RoadBond: 9 water.
Simply fill with material treated with RoadBond and compact.
Reworking of Treated Roads
RoadBond treated roads can be reworked because it is not a rigid setting agent like cement. In subsequent reapplications lower concentration of RoadBond can achieve the same results.
RoadBond can be used on playing fields, paddocks, stock yards, race tracks ,airstrips, golf courses, railways, etc. Its use will prevent dusting and reduce surface erosion.
The nature of the soil and the amount of loose material will determine the application rate. For a loose dust free surface, apply RoadBond as per 'Short Term Dust Control' treatment. for a hard bound surface apply as per 'Stabilisation'. In paddocks, fields and walkways, RoadBond does not impede plant or grass growth.
RoadBond and the Environment
Based on natural binding agents RoadBond is non-toxic and environmentally safe. The base ingredient, calcium lignosulphonate, is used as binder in animal foods.