Top 100 Geotechnical Terms Explained

Introduction: Understanding Geotechnical Engineering Terminology

Geotechnical engineering forms the foundation (literally!) of civil engineering projects. A strong grasp of its terminology is essential for professionals and students. This article compiles the top 100 terminologies in geotechnical engineering, complete with definitions, to enhance your technical vocabulary.

Top 100 Terminology with Definitions

1-10: Soil Mechanics Terms

1. Void Ratio (e): Ratio of the volume of voids to the volume of solids in a soil sample.
2. Porosity (n): Percentage of void space in a soil sample relative to its total volume.
3. Permeability (k): Measure of the soil’s ability to allow water to flow through it.
4. Shear Strength: Soil’s resistance to shearing stresses.
5. Consolidation: Gradual reduction of soil volume due to expulsion of water.
6. Cohesion: Attraction between particles in fine-grained soils.
7. Plasticity Index (PI): Difference between the liquid limit and plastic limit of soil.
8. Optimum Moisture Content: Water content at which soil reaches maximum dry density during compaction.
9. Liquefaction: Sudden loss of soil strength due to dynamic loading like earthquakes.
10. Effective Stress: Stress carried by the soil skeleton, excluding pore water pressure.

11-20: Foundation Engineering Terms

11. Shallow Foundation: A foundation that transfers building loads to the soil near the surface.
12. Deep Foundation: Foundations extending deep into the ground, such as piles.
13. Pile Cap: Concrete slab connecting multiple piles to distribute load.
14. Bearing Capacity: Maximum load a soil can support per unit area.
15. Settlement: Vertical movement of the ground due to load application.
16. Frost Heave: Soil expansion due to freezing water.
17. Raft Foundation: Large foundation slab supporting multiple columns or walls.
18. Cantilever Wall: Retaining wall with a projecting base slab.
19. Retaining Wall: Structure designed to hold back soil.
20. Gabion: A cage filled with stones used for erosion control.

21-40: Slope Stability Terms

21. Slope Stability: The ability of a slope to resist failure under its existing conditions.
22. Factor of Safety (FOS): Ratio of resisting forces to driving forces in a slope.
23. Landslide: Rapid downward movement of soil or rock on a slope.
24. Slip Circle: Circular failure surface in a slope.
25. Seepage Force: Force exerted by water movement through soil pores.
26. Erosion: The process by which soil and rock are removed by wind or water.
27. Creep: Slow movement of soil on a slope over time.
28. Reinforced Earth: Soil stabilized using geosynthetics or other reinforcements.
29. Rockfall: Sudden detachment of rock from a steep slope.
30. Anchor Bolt: Steel rod used to stabilize slopes or retaining walls.
31. Slope Reinforcement: Methods to improve the stability of a slope.
32. Debris Flow: Fast-moving landslide containing loose soil and water.
33. Berm: Horizontal step cut into a slope to reduce erosion.
34. Underpinning: Strengthening or stabilizing existing foundations or slopes.
35. Geogrid: Mesh material used to reinforce soil in slopes and retaining walls.
36. Critical Slip Surface: Surface with the lowest factor of safety in a slope.
37. Hydraulic Gradient: Slope of the water pressure line in soil.
38. Piping: Subsurface soil erosion caused by seepage flow.
39. Toe Erosion: Erosion at the base of a slope, leading to instability.
40. Retrofitting: Upgrading slopes or structures to meet safety standards.

41-60: Site Investigation Terms

41. Borehole: A drilled hole used to investigate subsurface conditions.
42. Standard Penetration Test (SPT): Test to measure soil resistance to penetration.
43. Cone Penetration Test (CPT): A test that measures the resistance of soil to a cone pushed into the ground.
44. Trial Pit: Shallow excavation for inspecting soil or rock layers.
45. Geotechnical Report: Document summarizing soil investigation findings.
46. Groundwater Table: Depth below which soil pores are fully saturated with water.
47. Sampling: Collecting soil or rock for laboratory testing.
48. Undisturbed Sample: Soil sample preserved in its natural state.
49. Core Barrel: Equipment used to extract cylindrical rock samples.
50. In-situ Test: Test conducted on the soil or rock at its natural location.
51. Seismic Refraction: Geophysical test to determine subsurface properties using seismic waves.
52. Auger Drilling: Drilling method using a helical screw to extract soil samples.
53. Resistivity Test: Test to measure electrical resistance of subsurface materials.
54. Dynamic Cone Penetrometer (DCP): Portable device to assess soil strength.
55. Percolation Test: Test to measure soil’s ability to absorb water.
56. Soil Profile: Vertical section showing soil layers.
57. Ground Investigation: Comprehensive study of ground conditions for construction.
58. Shear Box Test: Laboratory test to determine soil shear strength.
59. Atterberg Limits Test: Test to determine soil consistency limits.
60. Grain Size Distribution: Analysis of soil particle sizes.

61-80: Earthworks Terms

61. Earthworks: Construction activities involving soil or rock movement.
62. Cut and Fill: Excavation and placement of soil to create level surfaces.
63. Excavation: Removal of earth for construction purposes.
64. Compaction: Process of increasing soil density using mechanical means.
65. Bulking Factor: Increase in soil volume when excavated.
66. Shrinkage Factor: Decrease in soil volume when compacted.
67. Fill Material: Soil or rock used to raise ground levels.
68. Subgrade: Prepared soil layer beneath a pavement or slab.
69. Embankment: Raised structure of compacted soil or rock.
70. Backfilling: Refilling excavated areas with soil or other materials.
71. Rockfill: Embankment made of rock fragments.
72. Borrow Pit: Excavation site for obtaining soil or rock material.
73. Slope Dressing: Shaping and finishing slopes for stability.
74. Grading: Leveling and smoothing the ground surface.
75. Haul Road: Temporary road for transporting earthwork materials.
76. Riprap: Loose stone used to protect slopes from erosion.
77. Settlement Monitoring: Measuring vertical ground movement over time.
78. Dewatering: Removing water from soil to enable construction.
79. Geotextile: Fabric material used for soil separation and filtration.
80. Erosion Control Mat: Material used to prevent surface erosion.

81-100: Miscellaneous Geotechnical Terms

81. Overburden Pressure: Pressure exerted by overlying soil layers.
82. Stress Path: Variation of stress during loading and unloading of soil.
83. Kinematic Analysis: Study of possible failure modes in slopes.
84. Plastic Flow: Permanent deformation in soil under stress.
85. Swelling Pressure: Pressure exerted by soil when it absorbs water.
86. Void Ratio (e): Ratio of the volume of voids to the volume of solids in a soil.
87. Critical State Soil Mechanics: Theory linking soil volume, stress, and shear strength.
88. Hydraulic Conductivity: Soil’s capacity to transmit water.
89. Soil Stabilization: Improving soil properties using chemical or mechanical methods.
90. Retaining Wall Drainage: System to prevent water buildup behind walls.
91. Ground Anchor: Device used to transfer loads from structures to the ground.
92. Subsurface Investigation: Study of soil and rock layers below ground level.
93. Load Transfer Mechanism: Distribution of forces through soil or foundations.
94. Geophysical Survey: Non-invasive techniques for mapping subsurface conditions.
95. Soil-Water Characteristic Curve: Relationship between soil suction and water content.
96. Collapsible Soil: Soil prone to sudden volume reduction when wet.
97. Ground Improvement: Techniques to enhance soil properties for construction.
98. Earth Pressure: Lateral pressure exerted by soil on retaining structures.
99. Geohazard: Natural or human-induced events like landslides affecting stability.
100. Bearing Failure: Collapse of soil under excessive load from foundations.

Conclusion

Mastering these 100 geotechnical engineering terms will strengthen your understanding of the field, enhancing both academic and professional skills. Bookmark this glossary for easy reference and continued learning!

Let me know if you need further refinements or additional sections!

Saraswati Chandra Project Manager

See Full Bio