41 calculators · 11 categories
Geotechnical Tools for the Web
Free Interactive web calculators for geotechnical engineering, pavement design, and GIS workflows.
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41 tools
Foundations & Piles
Bearing Capacity Calculator (Shallow Footings)
Evaluate ultimate and allowable bearing capacity for strip, square, circular, and rectangular shallow footings using Terzaghi, Meyerhof, Hansen, and Vesic general equations.
Foundations & Piles
Deep Foundation Axial Capacity (Driven Piles & Drilled Shafts)
Calculate ultimate, allowable and uplift axial capacity of driven piles (alpha, lambda and beta methods) and drilled shafts (O'Neill & Reese 1999 / FHWA GEC-10) in layered soil, with IGM layers, belled bases, exclusion zones and large-diameter base reduction.
Foundations & Piles
CPT Pile Capacity (LCPC & Eslami–Fellenius)
Axial pile capacity direct from a CPT sounding by the LCPC (Bustamante & Gianeselli) and Eslami–Fellenius methods, with capacity versus embedded length.
Foundations & Piles
Pile Group Efficiency & Settlement Calculator
Calculate pile group reduction efficiency (Converse-Labarre, Sayed-Baker), cohesive block failure capacity (Skempton), and 2:1 equivalent raft immediate & 1D consolidation settlement.
Foundations & Piles
Lateral Pile P-y Curve Generator
Generate non-linear p-y response curves for laterally loaded piles in soft clays (Matlock 1970) and sands (API RP 2A) at varying depths.
Foundations & Piles
Lateral Pile Capacity (Broms Method)
Ultimate lateral load of single piles by Broms (1964) in clay and sand: free or fixed head, short, intermediate and long piles, with capacity versus length.
Foundations & Piles
Seismic Site Classification & Response Spectrum
Determine seismic Site Class (ASCE 7-16/22 & Eurocode 8) from 30m weighted average Vs30, N60, and su with live Design Acceleration Response Spectrum curves (Sa vs. T).
Foundations & Piles
Liquefaction Potential Analyzer
Calculate Factor of Safety (FS) against liquefaction using Idriss & Boulanger (2008) SPT methodology with magnitude and overburden corrections.
Retaining & Earth Pressure
Lateral Earth Pressure Calculator
Compute active (Ka), passive (Kp), and at-rest (Ko) lateral earth pressures using Rankine and Coulomb theories with slope, batter, water table, and surcharge superposition.
Retaining & Earth Pressure
Cantilever Retaining Wall Stability
Analyze sliding, overturning, resultant eccentricity, middle-third check, and base contact pressure distributions for cantilever retaining walls with interactive cross-section sketch.
Retaining & Earth Pressure
Sheet Pile Wall Design (Cantilever & Anchored)
Embedment depth, maximum bending moment and anchor force for cantilever and anchored sheet pile walls (free and fixed earth support) in layered soil with water.
Retaining & Earth Pressure
Seismic Earth Pressure (Mononobe–Okabe)
Mononobe–Okabe seismic active and passive earth pressure with wall friction, sloping backfill and batter: dynamic increment, resultant height and failure wedge.
Settlement & Consolidation
Elastic Settlement Calculator
Compute immediate elastic settlement under flexible and rigid footings using Theory of Elasticity (Harr / Bowles / Fox) and Schmertmann (1978) CPT strain influence method.
Settlement & Consolidation
Consolidation Settlement Calculator (1D)
Calculate primary consolidation settlement for normally consolidated (NC) and overconsolidated (OC) soils, secondary compression (Cα), and analytical pore pressure isochrones.
Settlement & Consolidation
Terzaghi 1D Consolidation Rate & Isochrones
Bidirectional solver for time factor (Tv) vs degree of consolidation (U%) and Fourier series excess pore pressure dissipation profiles for single/double drainage.
Settlement & Consolidation
Multi-Layer Settlement Analysis
Comprehensive static settlement calculation for multi-layer stratigraphy combining sand elastic modulus, Schmertmann CPT, and non-linear clay consolidation with Boussinesq stress attenuation.
Soil Mechanics & Lab Tests
Soil Phase Relationships & Weight-Volume Calculator
Solve all fundamental soil phase and index properties (w, e, n, Sr, Gs, γ, γd, γsat, γ') with bidirectional solver and interactive 3-phase soil block diagram.
Soil Mechanics & Lab Tests
Particle Size Distribution (PSD) Plotter
Interactive grain size analysis tool supporting standard ASTM sieves, manual entry, CSV upload, envelope ranges, D10/D30/D60/D90 calculation, Cu, Cc, and soil fraction percentages.
Soil Mechanics & Lab Tests
Atterberg Limits & Flow Curve Plotter
Plot the liquid limit flow curve (moisture content vs. number of blows on a semi-log scale) to automate the interpolation of the Liquid Limit, Plasticity Index, and Liquidity Index.
Soil Mechanics & Lab Tests
USCS Soil Classifier
Classify soil samples according to ASTM D2487 standard: coarse-grained, fine-grained, organic soils, dual symbols (GW-GM, SP-SM, etc.), and Casagrande plasticity chart.
Soil Mechanics & Lab Tests
Proctor Compaction Curve Analyzer
Fit laboratory moisture-density compaction test points with quadratic regression to determine Optimum Moisture Content (OMC), Maximum Dry Density (MDD), and Zero Air Voids (ZAV) curves.
Soil Mechanics & Lab Tests
Soil Permeability Calculator
Calculate soil permeability (hydraulic conductivity) using Constant Head Test, Falling Head Test, or Hazen's empirical formula.
Soil Mechanics & Lab Tests
Mohr-Coulomb / Triaxial Test Analyzer
Determine Mohr-Coulomb effective cohesion (c') and friction angle (φ') from triaxial or direct shear test stages using linear regression, and plot failure envelopes.
Soil Mechanics & Lab Tests
CPT Soil Behavior Type (SBT) & Correlation Calculator
Classify soil behavior type (Robertson 1990/2016) from CPT cone resistance (qc), sleeve friction (fs), and pore pressure (u2), with live SBT chart and correlations for su, φ', and N60.
Stress Distribution
Stress Distribution Calculator
Calculate vertical stress increase (Δσz) at any depth in a semi-infinite soil mass under point, line, and rectangular area loads using Boussinesq and Westergaard elastic theories.
Rock Engineering
RQD & Core Recovery Log
Calculate and visualize Rock Quality Designation (RQD) and Core Recovery profiles from drilling runs.
Rock Engineering
Rock Mass Classification Tool
Determine rock mass quality and engineering ratings using Bieniawski (1989) RMR89, Barton (1974) Q-System, and Hoek (2013) Geological Strength Index (GSI) matrix.
Rock Engineering
Hoek-Brown Rock Mass Strength Criterion
Generalized Hoek-Brown failure criterion (2002/2019) with equivalent Mohr-Coulomb parameters (c', φ'), deformation modulus (Erm), tensile strength, and live non-linear failure envelopes.
Rock Engineering
Stereonet Plotter & Analyzer
Plot planes and poles on a lower hemisphere equal-area (Schmidt) stereonet for structural geology and rock mechanics kinematic analysis.
Pavement Design
Equivalent Single Axle Load (ESAL) Calculator
Estimate cumulative traffic loading (W18) over a pavement design life using AASHTO traffic growth methodologies.
Pavement Design
CBR & Subgrade Correlations Calculator
Convert CBR or DCP index values into Resilient Modulus (MR) and Modulus of Subgrade Reaction (k) using standard AASHTO and MEPDG empirical equations.
Pavement Design
AASHTO Flexible Pavement Design
Calculate the required Structural Number (SN) and layer thicknesses for flexible pavements using the AASHTO 1993 design equation.
Pavement Design
AASHTO Rigid Pavement Design
Calculate the required concrete slab thickness (D) for rigid pavements using the AASHTO 1993 design equation.
In-Situ Testing & Geophysics
SPT N-Value Correction Calculator
Automatically correct raw Standard Penetration Test (SPT) blow counts to standard (N1)60 values used for design by applying overburden, energy, and sampler corrections.
In-Situ Testing & Geophysics
Shear Wave Velocity & Vs30 from SPT / CPT
Estimate the Vs profile and Vs30 from SPT (Imai & Tonouchi, Ohta & Goto) or CPT (Robertson, Mayne), with ASCE 7-16/22, NBCC and Eurocode 8 site classes.
In-Situ Testing & Geophysics
Drawdown Analyzer (Pumping Test)
Calculate aquifer Transmissivity and Storativity using Cooper-Jacob, and predict drawdown using the Theis well function.
GIS & Spatial Utilities
Spatial & GIS Format Converter
Convert and filter mapping and survey datasets seamlessly between GeoJSON, KML, KMZ, GPX, and CSV formats with geometry filtering and instant browser export.
GIS & Spatial Utilities
CSV to KML Batch Point Converter
Transform tabular borehole, CPT, and survey coordinate CSV files into styled Google Earth KML placemark files with custom column matching and data validation.
GIS & Spatial Utilities
Geometry Simplifier & Optimizer
Reduce vertex count and file size of heavy spatial datasets (GeoJSON, KML, KMZ, GPX) using Douglas-Peucker optimization with interactive Leaflet map preview and reduction metrics.
Units & Reference
Geotechnical Unit Converter
Convert geotechnical units: pressure (kPa, psf, tsf), unit weight (kN/m³, pcf), hydraulic conductivity, cv, force, moment, subgrade modulus, flow and slope.
Professional Practice
NPPE Practice Exam
Practice exams for the National Professional Practice Examination: 550+ questions on ethics, professionalism, tort law, contracts and intellectual property. Pick topics and length, bookmark questions, no sign-up.