The specific reactions between water and soil particles is examined here in detail.  In soil mechanics, it is usual to draw a distinction between two phenomena of water: static water and water in motion.  The motion is caused by penetration or by the action of gravity.  Water in motion greatly helps to accelerate many reactions initially by treatment with Endurazyme.  Static water, though it does not move under the actions of gravity, cannot be regarded as completely motionless.  The motion caused by osmotic forces or molecular movement is very slight, but over a long period of time, considerable masses of water may be transported as a result - either as a liquid or as a gas (evaporation).

Static water remaining in the soil can be divided into four categories differing from one another chiefly in the order of magnitude of the force with which they adhere to soil particles.
 

•  Chemical water, incorporated in the crystalline structure of the soil minerals.

•  Absorbed water which is held on the surfaces of the soil particles.
•  Water which is held by surface tension at the points of contact of the soil particles.

•  Capillary water in the pores between the soil particles.

The main function of Endurazyme is to reduce the amount of water held in the soil in order to form voids for optimum compaction and alternatively to decrease the swelling capacity of the individual soil particles, the characteristics of the categories of water in the soil will now be discussed.
 

CHEMICAL WATER,  which is incorporated in the crystal structure and is thus combines with he soil minerals.  It cannot be expelled by drying.  It can be regarded as an integral constituent of the soil.
 

ABSORBED WATER,  adhering to the surface of the soil particles can be partly, but not entirely, driven out by drying in an oven.  When soil dried out in this way is allowed to cool it will reabsorb water in amounts  dependent on the humidity of the ambient air.
 

WATER HELD BY SURFACE TENSION,  most of the water retained in soils is water which has been held by surface tension at the points of contact between particles or which otherwise can move as pore water or as free water in the capillaries and larger voids.
 

ABSORBED OR HYDROSCOPIC WATER,  is mainly responsible for the swelling or shrinkage properties of soils.  A soil particle with only chemically combined water cannot swell, i.e., it cannot alter its structural density.  Only the film of absorbed water adhering firmly to the particle surface can expand in volume as a result of further water absorption when the soil is wetted.  This effect is particularly prominent in fine-grained soils, such as clays.  Since this absorbed water is held in a "stable" form on the clay particles, thickening of this film will involve a displacement of the centres of the particles with overall effect that the volume of the mass of soil increases.

Therefore in order to achieve the densest possible packing of the clay particles and to obviate the swelling and shrinking behaviour of such soil, it is necessary to reduce the thickness of the water film (which is held firmly to the particles) or to break the film. The only way to do this permanently and economically is by ion exchange.

Due to Clays and Silts mineralogical composition they have an excess of negative ion's (anion) and therefore attract the positive ion's (cations) of water creating the formation of "Absorbed water".

Endurazyme by its chemical composition, has an enormous "potential" or ionic exchange.  When small quantities of the product are put in water which, then, vigorously exchanges its electric charges with the soil particles, breaking the electro-chemical bond of the absorbed water to become free water, which can then drain away by gravity, evaporation and compaction.  This electro-chemical reaction of ionic exchange is permanent, thereby creating lasting effects of soil stabilisation.

Once the "absorbed water" separates from the fines and drains as free water, though increased ion exchange and bonding trace elements particles settle are position in such a way that they attract each other.  A higher densification of the mass is achieved and practically eliminates the porous and capillary structure and the water suction by superficial tension.

The enzymes have an intrinsic ability to carry different charges simultaneously thus enabling the product to create the right cation exchange desired by sol mineralogy, to increase the cementation of particles on many number of different soil types.

To obtain a better understanding of this principle on which the operation of Endurazyme is based will be explained.

In this context the electrostatic characteristics of soil particles will also have need to be considered.  As a result of lowering the dipole moment of the water molecule there occurs dissociation into a hydroxyl (-) and  hydrogen (+)ion.  The hydrogen atom of the hydroxyl is transformed into a hydronium ion.  The latter can in the nascent state, accept or reject positive or negative charges, according to circumstances.

The hydrogen ion's which are liberated in the dissociation of the water molecules can once again react with free hydroxyl ion's and form water along with gaseous hydrogen.  It is important to note that the moisture content of the soil affects the surface tension and is thus a factor affecting compaction.

It should also be noted that dry soil is poorly suited for compaction only because of the surface tension of the water contained in it.  This is why a certain total quantity of Endurazyme solution is necessary for treating the area of ground in question.  This is important, for if less than the total required quantity of solution is applied, its penetration into the ground will be adversely affected.  The two phenomena of gas and water formation and surface tension can be reduced by an increase in moisture content.

If the forces involved can be reduced as a result of increased moisture content and Endurazyme wetting agent the Endurazyme solution can penetrate more easily into the capillary structure of the soil and the ion exchange process takes place more rapidly.  The water released in consequence can therefore either seep away or be expelled by the kneading action of, eg. a sheep foot roller, and then can evaporate at the surface.  Endurazyme therefore creates favourable conditions for compaction by changing the zeta potential of the clay and silt particles.

The zeta potential (electrokinetic potential) decreases with increasing concentration of the ion's of opposite charges from the Endurazyme solution.  The cations and anions are liberated from diffuse double layer which reduces the swelling properties of soil.
 

The shrinkage time diagram clearly shows a kind of sawtooth pattern with the teeth diminishing to zero over time.  It can thus be concluded that when water is added after shrinkage has occurred, the shrinkage decreases to an amount corresponding to the amount of capillary water that has emerged.

If the soil is allowed to dry so that water evaporates from it, the shrinkage that will then occur will never be quite as great as it was previously.  This accounts for the fact that surfaces treated with Endurazyme solution and left uncovered will always increase in stability over a prolonged period of time.

The most notable properties of Endurazyme and their effects on the soil therefore are:
 

•  Reduction of the dipole moment which has a water repelling effect on the individual soil particles and at the same time swelling capacity.

•  The electrokinetic phenomenon causes the stabilisation of the soil particles.  As a result of soil acquires a higher shearing strength and its compatibility is significantly improved.  In general the soil particles align themselves parallel to one another and because of the formation  of an electrical cushioning causes a sliding effect that takes place in the horizontal molecular structure.

•  Broadly speaking, a soil of colloidal character has which can contain a fairly large amount of voids which are filled wither with air or water.  During treatment with Endurazyme these voids must in any case be filled with pore water derived from the static water.  Only in this way can ion exchange be higher valency cations take place and the dipole moment of the soil particles be reduced.

When the reaction has occurred, less water can accumulate in the soil than was originally possible.  As a result, the swelling capacity is reduced, the internal moisture of the soil is reduced and greater compaction becomes possible because of the space that has become available from the pore water.

Subsequent additions of water cannot reverse this process and once the reaction has occurred the swelling capacity is destroyed and the shearing strength is increased.

Brian Jackson Sunday, 12/03/04

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