Civil and Building Engineering.

In the geotechnical investigation, a sample of soil or rock can be retrieved from a geologic stratum to be examined, classified, and tested using a variety of laboratory tests. In addition, several types of field tests are performed when necessary. It is desirable to obtain the soil and rock samples with minimal disturbance by the sampling process so that the results of testing in the laboratory are representative of the true nature of the soils in the particular stratum.

1 Grain-Size Distribution: The methods used to design foundations do not consider the size of the soil particles (also called grains) as a primary factor...

2 Types of Soil and Rock: Soil and rock are descriptive terms that have different meanings, depending
on their community of use...

3 Mineralogy of Common Geologic Materials: Clay minerals are complex aluminum silicates formed from the weathering
of feldspars, micas, and ferromagnesian minerals...

4 Water Content and Void Ratio: A soil sample is known to be saturated when it is weighed in the laboratory
and its total weight is W...

5 Saturation of Soil: A soil is composed of mineral solids and voids. The voids may be filled water, other liquids, or gas (air)...

6 Weight–Volume Relationships: Several relationships between weight and volume are frequently used by foundation engineers to compute the stresses in the soil due to gravity and the associated variation due to the location of the water table...

7 Atterberg Limits and the Unified Soils Classification System Atterberg Limits: The Swedish soil scientist A. Atterberg (1911) developed a method for describing quantitatively the effect of varying water content on
the consistency of fine-grained soils like clays and silts...