Use this geological calculation for a transparent first-pass interpretation of measured rock, soil, fluid, well, stratigraphic, isotopic, geophysical, or seismic data under an explicitly selected model.

e0

Initial void ratio e0 at the start of the increment.

d sigma'

Effective stress increase d_sigma' in kPa.

de

Decrease in void ratio de over the increment.

Oedometric (constrained) modulus E_oed = (1 + e0) * d_sigma' / de = 1 / mv from a consolidation loading increment. Void ratios dimensionless, stresses in kPa. The tool evaluates the supplied inputs together and returns the named outputs below; it does not infer omitted operating conditions or change the units shown.^[1]

E oed

Constrained modulus E_oed in kPa.

• Geological models are scale-, site-, method-, and calibration-dependent. Heterogeneity, anisotropy, sampling, diagenesis, pressure-temperature history, instrument response, boundary conditions, and empirical-correlation range can dominate the result.
• Use finite inputs in the displayed units and preserve more precision than the final presentation requires. Independently verify safety-critical, financial, compliance, or production decisions.

Compare independent measurements and models, retain units and analytical metadata, propagate uncertainty, and validate interpretations against logs, cores, maps, laboratory data, or field observations.

• Coefficient Of Volume Compressibility Calculator

  Coefficient of volume compressibility mv = av / (1 + e0), where av = de / d_sigma' is the slope of the e - sigma' curve over a loading increment. Result in 1/kPa.

• Compression Index Calculator

  Compression index Cc = -(de) / d(log10 sigma') = (e1 - e2) / log10(sigma2' / sigma1') from two points on the virgin consolidation curve. Void ratios dimensionless, effective stresses in kPa.

• Consolidation Settlement Calculator

  Primary consolidation settlement of a normally consolidated fine-grained layer Sc = H * Cc / (1 + e0) * log10(sigma_f' / sigma_i'). Assumes virgin compression with Cc; for overconsolidated ranges use Cr instead. Thickness in m, stresses in kPa, settlement in m.