Volume Relationships of soil
Volume relationships include the void ratio, the porosity, and the degree of saturation. The void ratio, denoted e, is the […]
Geotechnical Engineering
CIVIL ENGINEERS ARE IN THE MIDST of a construction revolution. Heavy structures are being located in areas formerly considered unsuitable from the standpoint of the supporting power of the underlying soils. Earth structures are contemplated that are of unprecedented height and size; soil systems must be offered to contain contaminants for time scales for which past experience is either inadequate or absent. Designs must be offered to defy the ravages of floods and earthquakes that so frequently visit major population centers.
All structures eventually transmit their loads into the ground. In some cases this may be accomplished only after circuitous transfers involving many component parts of a building; in other cases, such as highway pavements, contact is generally direct. Load transfer may be between soil and soil or, as in retaining walls, from soil through masonry to soil. Of fundamental importance is the response that can be expected due to the imposed loadings. It is within this framework that geotechnical engineering is defined as that phase of civil engineering that deals with the state of rest or motion of soil bodies under the action of force systems.
Unit Weight of soil
The ratio of the weight of a material to its volume is its unit weight, sometimes termed specific weight or
The Unified Soil Classification System (USCS)
The Unified Soil Classification System is based on the airfield classification system developed by A. Casagrande during World War II.
The Phase Diagram
In a typical volume of soil the three components are arranged in a complex mixture. To visualize the relationships among the
The AASHTO Classification System
The AASHTO system classifies soils into seven primary groups, named A-1 through A-7, based on their relative expected quality for
Specific Gravity of soil
To facilitate working problems across different sets of units, it is convenient to express the unit weight and density of
Soil problems Weight, Mass, Volume
Example 15.4 Assume that a compaction mold having a volume of 1/30 ft3 was filled with moist soil. The total
Grain-Size Characteristics of Soils
Large-grained materials such as cobbles and boulders are sometimes considered to be soil. The differentiation of cobbles and boulders depends
Density of soil
The term density is used herein to denote the mass-to-volume ratio of a material. However, some references, particularly older ones,