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ECOroads® Technical Q&A |
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Does ECOroads work well with organic materials (e.g. CaO, CaCO3)?
ECOroads works well with all organic soils. It will increase the bonding of the fines (-200 mesh) and allow greater moisture penetration to facilitate compaction. ECOroads has been used successfully in roads containing Limestone (CaO). Calcite (CaCO3), a fine grain limestone or soft earthy clay, also reacts positively with ECOroads. However, the use of clays should be minimized in road building - usually less than 30% - 200 mesh.
What is enzyme stabilization and why is it important?
Enzymes increase the compressive strength of soil. The enzyme acts as a catalyst to accelerate and strengthen road material bonding, creating a denser, cohesive and stable soil. Enzymes also reduce the compaction effort and improve soil workability while lubricating the soil particles. This makes the soil easier to grade and allows the compactor to achieve targeted soil density with fewer passes.
Enzyme stabilization also:
- Increases soil density: helps reduce voids between soil particles by altering electro-chemical attraction in soil particles and releasing bound water. The result is a tighter, dryer, more dense road foundation
- Lowers water permeability: Tighter soil configurations discourage the migration of water that normally occurs in the voids between particles. Greater resistance to water penetration deterioration.
- Is environmentally safe: Enzymes are natural, safe (organic) materials. These materials are non-toxic and will cause no harm or danger to humans, animals, fish or vegetation.
As time goes on will ECOroads reduce or increase in bonding strength? Will the road crack or become fragile?
ECOroads treated soils (for roads or ponds) achieve their greatest strength after the time of compaction and immediate subsequent curing (72 hours drying). Bonding of the soil particles takes place in the presence of moisture and compactive force. This condition will last as long as the material resists external forces. Heavy wheel loads, water, freeze-thaw cycles ultimately have an effect on all roads. ECOroads treated soils resists these forces due to the bonded, high density of the road material. The road will resist the detrimental effects of erosion and mechanical forces.
Cracking generally occurs as a result of two factors:
- Road material contains a high percent of expansive clays that have a high shrink/swell factor. When the road is completed and dries out, some cracking will appear. This can reduce the effectiveness of the road stability and affect longevity.
- Soft sub-base may not support the treated base under wheel loads, i.e. expansive clays. In this case, the bearing capability of the road is insufficient. This can be corrected by increasing the thickness of the road base.
Note that when the clay fines (minus 200 mesh) exceed 25% or are highly expansive, some surface cracking will occur. Generally the cracks are superficial, often filling in with road particles during normal traffic use. This condition is often referred to as "Alligator Cracking" and does not significantly affect the stability of the road base. Rain or other moisture will moderately swell the clay fines and the cracks will close. If the clay material is highly expansive, then the amount of fines should be kept low to reduce the amount of cracking.
Prior to placement of any surface material, ECOroads treated soil should be lightly sprayed with a dilute solution of water and ECOroads to assist in the bonding of the new surface material (i.e. asphalt) to the road base. Moisture will close many of the cracks.
Reflective cracks should not migrate upward through the asphalt, unless the clay fines are in the upper range and site conditions see radical sub-surface ground moisture variations. Proper drainage will reduce ground moisture and keep cracking to a minimum.
After compaction, what is the ratio of expansion? Will extreme weather affect the road (hot or cold)?
After compaction, the expansion-contraction ratio will be dependent upon the soil type (percentage of expansive clays) as well as the gradation range (distribution of particle sizes). Well-graded soil (ranging from -200 mesh to 1 inch) is ideal for road building. The -200 mesh fines should be approximately 20%. If the frost level extends below the level of the road, some heaving may occur. However, in the spring the road should settle back to is original elevation without severe damage. Proper road construction including shoulder drainage will minimize the effects of frost. Good engineering practices should be observed. Hot weather does not affect a road, other than dry dirt surfaces tend to be dusty under high wheel loading. ECOroads treated surfaces will reduce the amount of dust.
When the road contains more than 20-30% clay, will the road surface become too slippery and lose traction?
Road constructed with material containing a high clay contact will exhibit slippery surfaces when wet. It is necessary to use as much aggregate as possible to increase overall strength of the road and increase traction in wet conditions.
In many applications, surface treatment is applied as part of the overall design. This provides a wearing surface for traction, moisture protection, and greater overall strength. Cost and availability of materials are the primary factors affecting the type of surface treatment.
ECOroads works well with soils that have clay content passing a -200 mesh screen between 18%-30%. This range of fines has been indicated as an acceptable range for road building material. It is desirable to minimize excessive clay content. Under moist conditions the surface will not have proper surface friction and excessive plasticity may be present.
Over the course of four years ECOroads can reduce road maintenance by over 25%. For example, most roads typically required bi-monthly grading activities and periodic re-gravelling. If, however, ECOroads is used to stabilize the road, a thin "chip seal" is placed over the surface and a portion of the road is left bare. Substantial cost saving are obtained.
How long will the roads last when ECOroads is used?
ECOroads treated roads have been in use for over 5 years. The longevity of a road is a function of several factors:
- Climate conditions such as temperature ranges and rainfall
- Types of soils used in construction
- Road design - crowning, drainage and other engineered parameters
- Type of vehicular traffic, speed and degree of usage
- Wearing surface applied (if any)
- General maintenance frequency and quality
ECOroads treated roads retain their integrity over longer periods than previously experienced by road departments and require 50% less road maintenance. ECOroads treated road bases simply last longer.
Can temporary roads be constructed using less ECOroads?
Temporary roads might be constructed with reduced thickness, providing the wheel loads would not immediately destroy the road. ECOroads is always used at the rate of 1 gal per 165 cu yards or 1 liter per 33 cubic meters of soil material.
Is compaction required when using ECOroads?
ECOroads is used when moisture is applied to soil for compaction. Stability or stabilization occurs when soil particles are in close contact. Even when used in pond applications, the downward force of the water assists in compaction.
Spraying ECOroads on the soil without any compaction will not affect a change in erosion. The soil's ability to resist erosion is a function of the mineral makeup of the soil and compaction (or density).
Will ECOroads affect plant life if there is contact?
ECOroads is not harmful to plant life in its full range of various applications, i.e. road building, pond construction, etc.
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