FAQ

Question - As time goes on will Perma-Zyme reduce or increase its bonding strength? Will the road come out with cracks or become fragile?

Answer - Perma-Zyme treated soils (for roads or ponds) achieve their greatest strength at the time of compaction and immediate subsequent curing (72 hours drying). Bonding of the soil particles takes place in the presence of moisture and comp active 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. Perma-Zyme treated soil 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 occurs as a result of two factors: (1) If the road material contains a high percent of expansive clays – having a high shrink-swell factor. When the road is completed and dries out some cracking will appear. This reduces the effectiveness of the roads stability, however we have seen roads showing this condition that have performed very well – but with reduced life. (2) Soft sub-base may not support the treated base under wheel loads i.e. expansive clays. The bearing capability of the road is insufficient. This is corrected by increasing the thickness of the road base.

When the Clay fines (minus 299 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. Generally this condition is referred to as “Alligator Cracking” and does not significantly affect to 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, the Perma-Zyme treated soil should be lightly sprayed with a dilute solution of water & Perma-Zyme 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.

Question - After compaction, what is the ratio of expansion? Will extreme weather affect the road (hot or cold)?

Answer - 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 to road should settle back to its 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. Perma-Zyme treated surfaces will reduce the amount of dust.

Question - When the road contains more than 20-30% clay, will the road surface become too slippery and lose traction?

Answer - 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 not only increase overall strength of the road and increase traction as well 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, if any.

Perma-Zyme works well with soils that have a clay content passing a 200-mesh screen between 18% to 30%. This range of fines has been indicated as an acceptable range for road building material.

Various Transportation Deptarments have tested Perma-Zyme in soil that has a high clay content and found approx. 27% increase in unconfined compressive strength using Perma-Zyme. The soil tested was substantial clay with over 95 % passing a 200-mesh screen. The clay is classified as ‘FAT CLAY’.

In road building 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.

Question - How long will road last when used with Perma-Zyme?

Answer - Perma-Zyme treated roads have been in use for over 10 years. The longevity of a road is a function of several factors:

Climatic conditions such as temperature ranges and rainfall.

Type of soils used in construction.

Road design – crowning, drainage & other engineered parameters.

Type of vehicular traffic, speed and degree of usage.

Wearing surface applied (if any).

General maintenance – frequency and quality.

Experience shows that Perma-Zyme treated roads retain their integrity over long periods than previously experienced by road departments. Road Departments from various geographic areas have reported substantial reduction in road maintenance by over 50%. Perma-Zyme treated road bases last longer.

Question - Can temporary roads be constructed using less Perma-Zyme?

Answer - Perma-Zyme is always used at the rate of 1 gallon per 165 cu yds or 1 liter per 33 cu meters of soil material. Temporary roads might be constructed with reduced thickness, providing for wheel loads would not immediately destroy the road.

Question - What kind of equipment and method of construction is used to work on pond slopes?

Answer - Ponds are designed to engineered specifications, matching desired capacity with site topography, depth and with or without containment berms. Side slopes of the pond generally are designed with slopes not exceeding 3:1. consideration is given to equipment capability during construction, potential wave erosion and general usage.

Ponds generally are constructed using water trucks; Bulldozers, Motor graders and usually sheep foot compactors (due to high clay content). Perimeter berms are compacted in lifts to rough dimensions and bladed to finish elevations. Sometimes a bulldozer is used for this work due to the steepness of the slope.

Various combinations of equipment are used in difficult ponds. Bulldozer pulling a sheep’s foot compaction drum, or a clamshell excavator being used for grading the side slopes. Equipment availability often dictates what is built in the field.

Question - Is compaction required when using Perma-Zyme?

Answer - Perma-Zyme 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 Perma-Zyme on soil without any compaction will not affect a change in erosion. The soils ability to resist erosion is a function of the mineral makeup of the soil and compaction (or density).

Question - Will Perma-Zyme affect plant life if there is contact?

Answer - Perma-Zyme is not harmful to plant life in its full range of various applications, i.e. road building, pond construction, etc.