Geotechnical in Civil Engineering - Essay Example

Geotechnical Introduction Geotechnical involves a section of civil engineering that deals with the behavior of earth materials like soil. It is a vital field in mining, military, petroleum, and different engineering dealing with ground construction. Geotechnical engineering utilizes the principles of rock and soil mechanisms in investigating the physical condition of the subsurface material. The field is responsible for determining the required mechanical, physical, and chemical traits of the material.

In addition, geotechnical engineering deals with the evaluation of the stability of manmade deposits of soil, and the stability of natural slopes. Geotechnical engineering uses geophysical methods in measuring the physical properties of the earth's subsurface. These methods have the potential of measuring the anomalies in the properties of soil to identify the position and the presence of minerals (Das and Sobhan, 2013). They involve applying physical methods in measuring the physical traits of rocks and soil thus detecting the physical differences between the rocks that have hydrocarbons or ore deposits.

This paper explores the different types of geophysics methods and their use in geotechnical engineering. Electromagnetic methods electromagnetic induction (EM) involves a method that uses induction principles in measuring the electrical conductivity of the subsurface. Different from the techniques of conventional resistivity, EM requires no contact in the ground. This eliminates the fast problems of electrical coupling allowing much acquisition of rapid data. Since the EM instruments give an easy and rapid collection of data, the instruments are always used as the tools of reconnaissance used in identifying greatly detailed anomalies (Nobes, 2000).

The induced electromagnetic pulse can be measured using frequency domain meters and time domain meters. Ground penetrating radar methods.GPR (ground penetrating Radar is utilized in pinpointing the buried objects' location and mapping and having stratigraphy mapped out. It gives shallow subsurface cross-sectional measurements. The method has the ability to locate nonmetal and metal objects. In many cases, data and profiles are recorded and the result is shown using real-time having the attached display unit of the computer.

This results in a fast and easy field interpretation. More data interpretation could be done later (Nobes, 2000). The instruments of GPR have energy beamed into the ground from the antenna in the electromagnetic waveform. An energy position is reflected towards the antenna at the specific subsurface boundary where there exists some electrical contrast. Magnetic methods are effective and efficient methods of surveying large areas of underground iron and steel objects like barrels and tanks.

The earth magnetic measurement of the total magnetic field together with the gradients of local magnetic are established precession protons magnetometers at sections along lines that need to be oriented at higher angles of the suspected structure trends. In a local survey, the ambient field of the Earth can be taken as being uniform. The cultural magnetic and the local geological materials will express their distribution through perturbations in the field of the earth (Telford, Murray, and Sheriff. 1990). Seismic Methods These methods are commonly used in determining the geology, rock quality, and stratigraphy of a site.

The techniques give detailed information regarding the layering of the subsurface and the properties of rock geomechanical with the help of the acoustical seismic waves. Refraction and reflection are the seismic methods used commonly utilized (Telford, Murray, and Sheriff. 1990). The methods are used in determining the rock velocities and geological structure through reflecting or refracting waves off the boundaries of units of rock having different velocities of seismic or impedance (Das and Sobhan, 2013).