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. ?

The platelets in kaolinite carry negative charges which attract thick layers of adsorbed water reby producing plasticity.

Concept:

Clay Minerals

• Clay minerals and oxide minerals (including quartz) are most common byproducts of chemical wearing.
• Clay minerals are an important group of minerals because y are among most common products of chemical wearing, and thus are main constituents of fine-grained sedimentary rocks called mudrocks (including mudstones, claystones, and shales). 
• Clay minerals make up about 40% of minerals in sedimentary rocks.  In addition, clay minerals are main constituent of soils. 
• Clay minerals are used extensively in ceramics industry and are thus important economic minerals.  

Based on ir structures and chemical compositions, clay minerals can be divided into three main classes:

1. Kaolinite minerals
2. Illite minerals
3. Montmorillonite minerals

• Single-grained structure is characteristic of coarse-grained soils, with a particle size greater than 0.02mm.
• Gravitational forces predominate surface forces and hence grain-to-grain contact results.
• The deposition may occur in a loose state, with large voids or in a sense state, with less of voids

• This structure can occur only in fine-grained soils, especially in silt and rock flour.
• Due to relatively smaller size of grains, besides gravitational forces, inter-particle surface forces also play an important role in process of settling down.
• This results in formation of a honeycomb structure, each cell of a honeycomb being made up of numerous individual soil grains.
• The structure has a large void space and may carry high loads without a significant volume change.
• External disturbances can break down structure

• This structure is characteristic of fine-grained soils such as clays.
• Inter-particle forces play predominant role in deposition.
• Very fine particles or particles of colloidal size (< 0.001 mm) may be in a flocculated or dispersed state.
• The flaky particles are oriented edge-to-edge or edge-to-face for one anor in case of a flocculated structure.
• When inter-particle repulsive forces are brought back into play eir by remoulding or by transportation process, a more parallel arrangement or reorientation of particles occurs 
• This means more face-to-face contacts occur for flaky particles when se are in a dispersed state.
• In practice, mixed structures occur, especially in typical marine soils.

Soil structure is defined as arrangement and state of aggregation of soil particle in a soil mass.

Each cell in honeycomb structure is made of numerous single mineral grain.

When mass of particle increases, gravitational force acting downward on particle increases. Hence both mass and gravitational force are proportional to each or.

Moorum is gravel mixed with red clay. Peat is a highly organic soil which is highlt compressible and fibrous. Dune sand is non-plastic uniformly graded fine sand.

There are 6 types of attractive forces.
i) vanderwaal?s London force
ii) hydrogen
iii) bond, cationic linkage
iv) di-pole cationic linkage
v) water dipole linkage
vi) ionic bond.