The silicon sheet is represented by trapezoidal symbol, representing oxygen basal layer and hydroxyl apex layer.

Explanation:

Flocculent Structures

• These are found in soils having a size of less than 0.0002 mm.
• The fine particles are mostly flaky, platelets, and not spherical, and contain surface electric charges.
• The formation of se soils is due to surface electric force and not due to gravity force.
• It enclosed a large volume of voids.
• It has high sensitivity which is disturbed when soil is remolded and thus converted into a Dispersed structure.
• In this clay particles connect edge to edge or edge to face.

Additional InformationSingle grained soil

• It is found in soils having a size great than 0.02 mm.
• The major force is gravity force, and surface electric force is negligible.
• For example-gravels and sands.

?Honeycomb structures

• It is found in soils having sizes of 0.02 mm to 0.002 mm.
• Gravity force and surface electric force both play a role in formation.
• These soils enclosed a large volume of voids.
• The adhesive forces hold particles toger.
• When structure unbroken such soils may have ability to bear high load, but once structure destroys, load-bearing capacity reduces suddenly.
• For example- silt. ?

Coarse grained skeleton is a composite structure. Composite soil with a large amount of coarse grained particles form ?coarse grained skeleton?. While composite soil with a large amount of fine grained particle form ?clay matrix?.

As surface activity of clay minerals is high y develop a property of cohesion and plasticity.

In octahedral unit, aluminum, iron or magnesium atom are enclosed in six hydroxyls having configuration of an octahedron.

The edges of two kaolinite crystal are joined by two cations. Hence cationic linkage bond exist in kaolinite crystal.

The single grained structure is characteristic of coarse-grained soils. The honeycomb, flocculent and dispersed structures are found in fine-grained soils.

Interatomic or intermolecular distance of secondary valence bond is >5 Å.

The nature of surface bonding is classified into three types as primary valence bond, hydrogen bond, secondary valence bond.

An arrangement of coarse grains forming a skeleton with its interstices partly filled by relatively loose aggregation of finest soil grains is shown in coarse-grained skeleton structure.