Structural and Civil Engineering Curriculum

Soils

Module from the Structural and Civil Engineering Curriculum curriculum.

Module 2 - Soil Investigation and Bearing · Learning Objectives · 1. Interpret geotechnical report: SPT N-value, CPT qc, shear strength Su · 2. Estimate allowable bearing from presumptive values (IBC Table 1806) · 3. Screen for liquefaction in sandy soils with shallow groundwater · 4. Identify expansive clay requirements (undercut, lime stabilization) · 5. Plan dewatering for excavations below groundwater · Presumptive Bearing Values (IBC Table 1806.2)

Soil Type	Allow Bearing (psf)	Notes	Typical Use	Settlement Risk	Ref
Crystalline bedrock	12000+	Hard, rocky	Large foundations	Minimal	IBC
Sedimentary rock	4000+	Soft rock	Tank foundations	Small	IBC
Dense sand/gravel	3000	GW/GP	Typical refinery	Small	IBC
Medium dense sand	2000	SW	Common	Moderate	IBC
Loose sand	1000-1500	SP	Caution	High	IBC
Stiff clay	2000	CL	Compact	Moderate	IBC
Soft clay	500-1000	CL	Not for heavy equipment	High	IBC
Organic silt/peat	Special	OH/PT	Avoid or pile	Very high	IBC

Source: Structural_Civil_Engineering_Curriculum_v1.xlsx · Sheet: Soils

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