Terminology

Auger	a tool having a helical shaft that is used for boring holes into the ground and removing the loosened soil
Axial	the direction perpendicular to the plane of the top of the pile
Bulging	is a portion of a pile, which protrudes beyond the nominal diameter of the pile. This occurs when piles are bored through strata of soils with differing density. Bulging occurs when good practices are being observed.
Clay	an earthy material that is plastic when moist but hard when fired, that is composed mainly of fine particles of hydrous aluminum silicates and other minerals
Communication	is a term used to indicate that piles have been placed too close together while the concrete grout is still fluid. Visual observations of changes in levels of grout in the pile(s) above or below the ground indicate the adjacent shaft may have expanded . This may have pinched off or reduced the shaft diameter of the adjacent pile. Florida Building Codes recommend 24 hours between adjacent piles spaced within 6 pile diameters.
Compression	to apply a downward vertical load to a pile
Concrete Grout	a mixture of cement, water and sand or chemicals that solidify
Cores	are cylindrical samples of rock which are obtained from drilling and tested for compressive strength
Pile	a long slender column composed of solidified concrete grout constructed in the ground to carry a vertical load
End Bearing	the force that resists motion between the tip of the pile and the soil/rock.
Friction	the force that resists relative motion between the surface of the pile and the contact with the soil
Geotechnical Report	a summary report of the exploration of the subsurface soils and how they are to be used as construction materials.
Group effect	a group of piles under load will behave differently than individually loaded piles
Head	is a term that normally refers to the height in feet that the concrete grout is above the tip of the auger discharge bit as it is being withdrawn from the hole. While this can’t be measured because it is below the ground it is normally estimated by observing height the grout on the auger after it is totally withdrawn from the hole.
Impenetrable	incapable of being penetrated
Karst	is a geological term which describes the conditions existing in limestone formations containing solution filled cavities and voids.
Neat Line volume	refers to the volume of a cylindrical shaft of a given diameter and length.
Necking	is a condition most feared by engineers and designers. Should the withdrawal rate of the auger exceed the replacement rate of the concrete pumped into the pile the soil may collapse and make the pile shaft smaller than nominal. In other cases shaft could be discontinuous. This could result is serious structural inadequacies.
Negative Skin Friction	is a condition when piles are placed though compressible strata where the skin friction on the pile above the compressible layer is considered to reduce the overall load carrying capacity of the pile.
Overage	is a term that refers to the amount of concrete used in excess of the Neat Line Volume of a cylindrical shaft of a given diameter.
Overage factor	Is the Estimated Volume of Concrete pumped divided by the Neat Line Volume of the hole. Most engineers specify a minimum of 115%.
Overflightling	is a theoretical condition which occurs when a continuous helical auger is rotated into the ground and excessive soil is removed . It is thought that this condition may cause a reduction in the soil density and thus a reduction in available skin friction between the soils and the pile surface. Overflighting may be considered occurring when large depressions occur around the hole while it is being installed..
Penetration	the action of passing through
Pile Load Test	is a test to determine the safe load carrying capacity of a pile. As loads are superimposed on a pile the load deflection and given intervals are recorded and analyzed. Reaction systems for applying loads to test pile can consist of weighed blocks or anchor piles with steel beams. Recent advances in testing procedures include "Statnamic" testing. Higher design loads are more adequately evaluated using this methodology. Both compressive and tensile data can be derived from one load test. Test piles are instrumented with strain gauges at various depths to provide additional engineering design data. http://www.testpile.com/
Pile Caps	are steel reinforced concrete structures , normally square or rectangular, of a thickness which combine piles in groups to support singular columns above.
Positive Concrete pressure	is thought to be the pressure that is required to maintain the shaft of concrete when extracting the auger during casting of the pile. There are varying beliefs on the pressure required and where the pressure should be measured. Because there are numerous factors which affect the line pressure such as , concrete consistency, height, length of supply hoses, location of gages and pump ability, there is not a known authority on this subject.
Rock	consolidated or unconsolidated solid mineral matter
Safety Factor	is a multiple of safety greater than 1 that is applied to the design load carrying capacity of a pile. Engineers and codes may specify the factor of safety depending on the structure that is being supported. Most codes require a safety factor of 2. This is sometimes increased depending on the amount of information available about the site.
Sand	a loose granular material that results from the disintegration of rocks, consists of particles smaller than gravel but coarser than silt
Silt	loose sedimentary material with particles usually 1/20 millimeter or less in diameter
Soil Test Boring	a bore hole drilled or augered into the ground in which soils are sampled at intervals, obtained and classified.
Standard Penetration Test Boring	is the sampling of soils using a standard procedure in which a sampler of a given size driven into the soil with a 140 pound hammer falling from a height of 30 inches. The number of blows of the hammer is recorded for each successive 6 inches of penetration for a total of 18 inches. The total number of blows for the last 12 inches is called the “N” Value. See ASTM.
Standard Penetration Test Boring Log	The a graphical representation of the inferred subsurface soil strata recorded at depth with it’s corresponding “N” Value.
Strata	soil or rock of one kind lying between beds of other kinds
Unified Soil Classification System	is standard system of classifying soil by particle size and characteristics.
Volume	is normally expressed in Cubic Yards. It is calculated by multiplying 3.1416 times the radius squared times the length. The Neat Line volume is referred to as 100%.
Weathered	is a term that described the condition of limestone that is weakly cemented together.

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