Geotechnical Engineering · Engineering Glossary
A soil boring is a subsurface investigation technique in which a drilling rig advances a hollow rod into the ground to collect soil samples and measure soil resistance at regular intervals. The data from soil borings is analyzed by the geotechnical engineer to characterize the soil profile, determine bearing capacities, and identify any problematic conditions.
Standard Penetration Tests (SPT) are conducted within the boring by counting the number of hammer blows required to drive a split-spoon sampler 12 inches — the N-value indicates relative soil density. Undisturbed tube samples are collected from fine-grained soils for laboratory consolidation and shear strength testing. The depth and number of borings depends on the project size, load levels, and variability of soil conditions; most commercial sites require 3–8 borings to an adequate depth. The geotechnical engineer assembles the boring data into a geotechnical report with foundation recommendations, bearing pressures, and site-specific seismic site class determination. Apex Grid coordinates project scope and boring locations with the geotechnical subconsultant.
Apex Grid Engineering maintains this glossary as a resource for architects, contractors, developers, and property owners who encounter unfamiliar engineering terminology on their projects.
View All Engineering TermsApex Grid's licensed PEs provide geotechnical engineering services across multiple jurisdictions — with fast quote turnaround and permit-ready documents.
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