Calculator library
Every calculator, A–Z by discipline
411 free civil and structural engineering calculators across 16 fields. Each page shows the inputs, a worked example with results and checks, the method and the standard, with a link to the live calculator.
Steel 60 Concrete 37 Timber 14 Masonry 10 Foundations 46 Retaining & slopes 27 Ground engineering 43 Site investigation 64 Pavements & traffic 15 Hydraulics & drainage 16 Bridges 8 Analysis & loading 26 Temporary works & site 11 Utilities 2 Construction & estimating 31 Project controls 1
Steel calculators
- Base plate shear lug
Lug embedded below grout: concrete bearing on the lug, lug cantilever bending and the lug-to-plate fillet welds. - Beam lateral–torsional buckling (restraint options)
Segment capacity with restraint arrangement, load height and rotational restraint factors and αm options, for library… - Beam-column interaction (I-section)
Section capacity reduced for axial load, in-plane member capacity and out-of-plane (lateral buckling) interaction for… - Block shear rupture
Block shear with the AS 4100 rupture/yield shear plane options and kbs for non-uniform tension. - Bolt design & bolt group
Bolt shear, tension, bearing and tear-out; eccentric bolt group by the elastic method. - Bolt in combined tension & shear (with prying)
Bolt tension capacity, prying allowance and the elliptical shear–tension interaction. - Bolt in shear & ply bearing
Single bolt shear capacity with threads in / excluded from shear planes, ply bearing and end tear-out; bolt category… - Bolted flange splice (cover plates)
Flange force from moment and axial share; outer cover plate tension yield/fracture and short-column compression; bolts… - Bolted moment end plate (extended, 8.8/TB)
Extended end plate on a UB beam framing into a UC column flange. The flange force M*/(d − tf) goes to the two bolt… - Bolted web splice
Web carries the shear plus its share of moment (Iw/I); double web plates; bolt group polar analysis with eccentricity… - Bracing gusset (Whitmore, Thornton, block shear)
Whitmore effective width, gusset tension yield and fracture, compression buckling over the Thornton length, and block… - Butt-welded splice (CP / IP)
Complete penetration butt weld at parent strength, or incomplete penetration treated as a fillet on the design throat. - Car-park vehicle barrier (impact energy)
Steel-post edge barrier in a car park. The impact force is found from the kinetic energy ½mv² absorbed by the… - Cast-in anchor: concrete cone & steel (simplified)
Characteristic cone breakout with projected-area group and edge factors, steel tensile failure, and design resistance… - Castellated beam (net tee checks)
Parent I-section expanded by the cut depth: global bending carried as tee axial forces, Vierendeel bending of the tees… - Column base plate (axial)
Concrete bearing capacity with confinement and required plate thickness for a concentrically loaded column. - Column cap plate & beam web bearing
Beam sitting on a column cap plate: stiff bearing length with dispersion through flange and plate, web yield, and cap… - Composite steel–concrete beam
Effective width, plastic neutral axis in the slab, positive moment capacity and stud count for full shear connection. - Compression member: CHS
CHS compression capacity computed from outside dimensions and thickness, with the local buckling form factor. - Compression member: PFC channel
Channel strut with properties computed from d, bf, tf, tw and capacity about both axes. - Compression member: SHS / RHS
SHS/RHS compression capacity computed from outside dimensions and thickness, with the local buckling form factor. - Compression member: single equal angle
Equal angle strut: area and minor principal radius rv from dimensions, local buckling kf and member capacity… - Compression member: UB / UC (library)
Major and minor axis member capacity for library or custom I-sections, with independent effective lengths. - Corrosion allowance & coating life
First-year corrosion rate by category, long-term thickness loss per side with the ISO 9224 power law, remaining… - Crane runway beam (two wheels)
Maximum moment from two moving wheels (Barré position), dynamic factor, lateral surge on the top flange and biaxial… - Crane runway beam with fatigue
Simply supported runway beam under the two wheels of an overhead travelling crane end carriage. Maximum wheel loads… - Deflection limits checker
Maximum deflection of simply supported, propped, fixed or cantilever members under UDL and point load, against… - Double angle web cleat
Two angle cleats bolted to the beam web (double shear, eccentric) and to the support (single shear), with angle shear… - Embedded plate with headed studs (anchor group)
Steel plate cast into a concrete element with a rectangular group of welded headed studs, loaded in tension and in… - Extended end plate (4-bolt unstiffened)
Bolt rows either side of the tension flange share the flange force; plate checked as a T-stub; compression-side bolts… - Fillet weld group
Fillet weld capacity per mm and an eccentric weld group (two lines or all-round) by the elastic method. - Fin plate (shear tab) connection
Single vertical line of bolts with eccentricity, plate shear yield and rupture, block shear, plate bending and the… - Fire: limiting steel temperature
Limiting temperature from the load ratio, yield stress and modulus reduction factors at a given temperature, and… - Fixed column base plate with anchor bolts
Axial load plus moment: stress-block length, anchor tension, bearing stress, and plate thickness on both the… - Floor vibration from walking (AISC Design Guide 11)
Natural frequency from the deflection of the floor system under its in-service weight, the predicted peak acceleration… - Flush end plate moment connection
Bolt tension from elastic distribution about the compression flange, end plate thickness from a double-curvature… - Friction-type bolted joint (8.8/TF)
Slip resistance with faying-surface slip factor, hole type factor and tension interaction. - Lifting lug (plate with pin hole)
Plate lifting lug loaded through a pin at a sling angle in its plane: net tension, tear-out above the hole, pin… - Load-bearing web stiffener
Bearing yield of web plus stiffener pair, and buckling of the stiffener with the effective web strip as a column of… - Pin connection
Pin in double shear, pin bearing, pin bending between plates and the lug net tension across the pin hole. - Portal frame (pinned base)
Gable portal analysed by the stiffness method for 1.2G + 1.5Q and 0.9G + Wu; knee and ridge moments, reactions… - Portal frame with second-order effects (AS 4100)
Pinned-base gable portal analysed by the stiffness method for three combinations, then amplified for second-order… - Portal knee: column web panel zone
Shear in the column web panel from the rafter moment; diagonal stiffener area required if the web is overstressed. - Portal rafter
Steel UB rafter for a portal shed: gravity and wind-uplift combinations, flange restraint and deflection. - Purlin / girt check
Gravity and uplift moments for single- or double-span purlins and girts, compared with the section's design capacity… - Purlin cleat under uplift
Purlin cleat welded to a rafter: bolt shear from wind uplift and downslope load, cleat bending at the weld toe. - Rod bracing (tension-only)
Brace force from the bay shear and geometry with a prestress allowance, threaded rod capacity on the tensile stress… - Sheet pile wall: section, tie rod, waling & deadman
Required section modulus of the sheet piles, tie-rod diameter, waling size and continuous deadman capacity and… - SHS / RHS beam: bending & shear
Section modulus and compactness of a rectangular hollow section in major-axis bending, web shear capacity and… - Small steel-framed house (preliminary)
From plan, roof pitch, wind region and terrain: site wind speed and class, then purlin, rafter, stud and lintel sizes… - Spreader beam (CHS strut) for a two-point lift
Compression in the spreader from the sling angle, bending from self-weight, member capacity of the CHS as a pin-ended… - Stair stringer
Inclined stringer carrying half the stair: horizontal-span moment, shear, and deflection along the incline. - Steel angle lintel
Equal-angle lintel over a masonry opening with triangular (arching) or full masonry load. - Steel beam (UB)
Section and member moment capacity (lateral-torsional buckling), shear and deflection, with built-in UB sizes. - Steel column (AS 4100 compression + bending)
Section and member compression capacity about both axes, moment capacities and combined-action utilisation for UB/UC… - Steel I-beam in torsion with warping
UB or UC simply supported with fork ends (twist prevented, warping free) carrying an eccentric point load at midspan… - T-stub in tension with prying (Thornton)
Available bolt tension of a T-stub flange including prying; thickness for no prying, α′ and Q. - Tension member: net area & stagger
Gross yield and net-section fracture with staggered holes (s²t/4g) and the correction factor kt for eccentric end… - Web bearing: yield & buckling
Unstiffened web bearing yield (1.25 bbf tw fy) and bearing buckling with αc at le/r = 2.5 d1/tw for library or custom… - Welded plate girder (flexure & shear)
Section properties from plates, effective section modulus with flange/web slenderness, web shear buckling with…
Concrete calculators
- Basement wall propped top and bottom
Basement wall spanning vertically between the floor slab at the top and the basement slab at the bottom, loaded by… - Circular RC column: N–M interaction
Circular column or pile section with bars evenly spaced round a circle. The interaction curve is built by strain… - Circular water tank wall
Hydrostatic hoop tension, hoop reinforcement for a limiting steel stress and stored volume. - Column biaxial bending (AS 3600)
Load-contour check (Mx*/φMux)^αn + (My*/φMuy)^αn ≤ 1 for a rectangular column, with the exponent αn derived from the… - Composite slab (steel deck)
Positive moment capacity of a composite slab with the profiled deck acting as reinforcement, vs factored moment. - Concrete bearing stress
Bearing capacity under a plate with the √(A2/A1) enhancement capped at 2.0. - Concrete cores: corrected strength and acceptance
Core compressive strengths corrected for length/diameter ratio, the mean and the lowest, against the usual in-situ… - Concrete material properties
Mean in-situ strength, Ec from density, flexural and direct tensile strength, and the stress-block parameters for a… - Concrete NDT: half-cell potential survey
Converts readings to the copper/copper-sulfate scale and classifies each point: > −200 mV low (90 % no corrosion)… - Concrete NDT: ultrasonic pulse velocity and crack depth
Pulse velocity through the member and its quality grade, dynamic modulus, and the depth of a surface crack from… - Continuous beams and slabs: AS 3600 simplified moment coefficients
Design moments and shears from the AS 3600 coefficients for continuous beams or one-way slabs of near-equal spans… - Corbel (strut-and-tie)
Single strut-and-tie model: tie force including horizontal restraint, tie steel, strut angle and strut stress with βs. - Corbel or nib: strut-and-tie design
Short cantilever (av/d ≤ 1) carrying a vertical reaction V* and a horizontal restraint force H* (≥ 0.2V* for precast… - Creep coefficient
Design creep coefficient from the basic value for f′c, maturity (k2), age at loading (k3) and environment (k4). - Design shrinkage strain
Autogenous plus drying shrinkage at time t with the hypothetical thickness, environment factor and basic drying strain… - Development & lap length
Development length of deformed bars in tension and tension lap length. - Doubly reinforced RC beam
Rectangular beam with compression steel: neutral axis by trial on compression-steel yield, capacity and ductility. - Grouted duct anchorage and panel joint shear friction
Starter bars from a footing or slab grouted into corrugated ducts in a precast panel. The embedment must develop the… - Load balancing (parabolic tendon)
Equivalent upward load wp = 8Pe/L², balanced fraction of the permanent load, and average precompression. - Moment–curvature (RC section)
Full M–φ response of a rectangular RC section: cracking, first yield and ultimate, with curvature ductility. - One-way slab
Bending steel, bar spacing and deemed-to-comply span/depth for a one-way slab. - Post-tensioned flat slab: load balancing, stresses, punching
Interior panel of a bonded post-tensioned flat plate. The tendon drape balances a chosen share of the self-weight (P =… - Post-tensioning friction & draw-in losses
Force along a parabolic tendon from curvature and wobble friction, and the length affected by anchorage draw-in. - Prestressed beam fibre stresses
Top and bottom fibre stresses at transfer and service for a rectangular section with eccentric prestress. - RC beam (flexure + shear)
Singly reinforced rectangular beam: tension steel, ductility and shear with stirrups. - RC beam torsion with shear (AS 3600 Cl 8.3)
Rectangular beam under combined torsion and shear. Checks whether torsion can be ignored (T* ≤ 0.25φTuc), web crushing… - RC cantilever retaining wall stem
Factored earth and surcharge moment at the stem base, vertical reinforcement and shear capacity (pair with the… - RC column (N–M interaction)
Short rectangular column, uniaxial bending: interaction diagram, minimum moment and slenderness. - RC deflection and crack control
Short-term and long-term deflection of a simply supported RC beam or slab strip using Ief, and the service steel… - RC T-beam flexure (flange in compression)
Rectangular stress block in a T-section: neutral axis in the flange or web, moment capacity, ductility (ku) and… - RC wall: in-plane shear and simplified axial capacity
Braced reinforced concrete wall resisting in-plane horizontal shear and vertical load. Shear capacity Vu = Vuc + Vus… - RC wall: simplified axial capacity
Braced wall design axial strength per unit length with eccentricity and the slenderness eccentricity ea = Hwe²/(2500… - Slab punching shear (AS 3600)
Critical shear perimeter at dom/2, concrete capacity fcv, and moment-transfer reduction for an interior, edge or… - Slender RC column (moment magnifier)
Slenderness, buckling load Nc, moment magnifier δb and the magnified design moment checked against the N–M interaction… - Staircase (waist slab)
Self-weight of steps and waist, bending reinforcement for a flight spanning horizontally, and riser/going checks. - Tilt-up panel: lifting and in-service design
Tilt-up wall panel. Lifting: the panel is raised from the casting bed on two or four rows of inserts; the peak bending… - Two-way slab
Moments in both directions for a rectangular slab simply supported on four edges.
Timber calculators
- Bolted timber joint at any angle to the grain
Timber joint with a group of bolts loaded at an angle to the grain. The characteristic capacities parallel and… - Bracing walls: racking force and capacity
Wind racking force on a house or shed in one direction from the area of the elevation (half the wall height plus the… - Flitch beam (timber with a steel plate)
Two timber members bolted either side of a steel plate. Moments share in proportion to EI; each material is checked… - Glulam / LVL beam (AS 1720.1)
Simply supported glulam or LVL beam carrying a floor or roof strip. Design capacities φk1k12·f′b·Z and φk1·f′s·As for… - Nailed timber joint (AS 1720.1 Sec 4)
Nailed timber-to-timber or steel-plate-to-timber joint. Lateral design capacity Nd = φ·k1·k13·k14·k16·k17·n·Qk with… - Timber beam / joist (AS 1720.1)
Bending and shear capacity with load-duration factor k1 and long-term deflection with j2 for MGP, F-grade and glulam… - Timber beam shear
Shear capacity with As = (2/3) b d for rectangular sections. - Timber bearing perpendicular to grain
Bearing capacity with the bearing-length factor k7. - Timber column (compression)
Compression capacity with slenderness coefficient S, stability factor k12 and the material constant ρc. - Timber combined bending & compression
Interaction (M/φMx)² + N/φNcx ≤ 1 and M/φMx + N/φNcy ≤ 1 for a rectangular member. - Timber floor vibration & long-term deflection
Joist fundamental frequency, deflection under a 1 kN point load, and long-term creep deflection with j2. - Timber pile (structural + geotechnical)
Compression capacity of a tapered round timber pile at ground level (with stability factor k12) and at the toe, and… - Timber tension member
Tension capacity parallel to grain on the net area after holes. - Timber wall stud: axial load and wind
Load-bearing stud carrying the roof or floor load and face wind pressure. Slenderness about the major axis uses the…
Masonry calculators
- Cavity wall: load sharing and wall ties
Two masonry leaves joined by ties across the cavity, spanning vertically between supports. Wind on the outer leaf is… - Concentrated load on masonry with a padstone
Beam reaction bearing on a masonry wall, first directly and then through a concrete padstone. The bearing factor kb… - Masonry lintel loading with arching
If enough masonry stands above the opening the lintel carries only a 45° triangle of masonry; otherwise the full… - Masonry panel in two-way bending
Unreinforced masonry panel supported on four sides, or three sides with the top free, under uniform face pressure… - Masonry wall with an opening: piers, lintel, bearing
Unreinforced masonry wall with a window or door opening carrying a line load from the floor or roof. Load to each pier… - Reinforced masonry retaining wall
Core-filled blockwork stem on a reinforced concrete base. Rankine active pressure with surcharge; sliding… - Reinforced masonry shear wall (AS 3700)
Core-filled reinforced blockwork wall racking under an in-plane horizontal force. Shear capacity Vd = φ(fvr·Ar +… - Reinforced masonry wall: out-of-plane bending
Bending capacity per metre of a reinforced core-filled block wall, with the steel ratio limit. - Unreinforced masonry wall: compression
Characteristic masonry strength from the unit strength, slenderness Srs and reduction ks, design compressive capacity… - Unreinforced masonry: vertical bending
Vertical bending capacity per metre using the flexural tensile strength f′mt plus the precompression, against a…
Foundations calculators
- Axial pile load–settlement by t-z / q-z curves (API RP 2GEO)
Unit shaft friction and end bearing by the API method (α in clay, β in sand), then the pile is marched up from the toe… - Bearing capacity
Ultimate and allowable bearing pressure for strip or rectangular footings with shape and depth factors. - Bi-directional (O-cell) test: equivalent top-down capacity
Fits hyperbolas to two points on the upward (shaft) and downward (base) curves and adds them at a common displacement… - Combined footing (two columns)
Length placing the resultant at the centroid (uniform pressure), width for allowable bearing, and maximum longitudinal… - Crosshole sonic logging: profile rating
Rates every reading of one tube-pair profile against the median first arrival time (FAT) and energy: Good ≤ 10 % / < 6… - Driven pile capacity from SPT (Meyerhof)
Shaft friction layer by layer from SPT N and base resistance from N at the toe with the embedment into the bearing… - Dynamic pile test (PDA): CASE method capacity
From the force and velocity measured at the pile head at the peak (t1) and one wave return later (t1 + 2L/c): total… - Footing settlement & stress distribution
Immediate settlement of a rectangular footing plus consolidation of a clay layer, with the vertical stress increase… - Footing uplift resistance
Uplift capacity from footing self-weight plus the soil frustum spreading at angle α, against wind uplift. - Helical (screw) pile capacity
Compression capacity as the sum of helix bearing (c Nc + q′ Nq) plus torque-correlated capacity for comparison. - Impulse response (mobility) test: length and impedance
Length from the spacing of resonant peaks in the mobility spectrum, and the equivalent diameter from the measured… - Laterally loaded pile (Broms)
Ultimate lateral resistance of a free-head pile in sand or clay, short (rigid) or long (yielding) mode. - Laterally loaded pile: p-y analysis (Matlock clay, API sand)
The pile is a beam on non-linear soil springs solved by finite differences with secant-stiffness iteration. Layers use… - Layered settlement under a rectangular footing (Fadum + oedometer)
Stress increase at the centre of each layer by the Fadum influence factor, the layer settlement Δσ·h/Eoed, the total… - Low-strain pile integrity test (PIT): length and impedance
Pile length from the toe echo time, depth of an anomaly, and the impedance ratio and equivalent diameter implied by… - Micropile (grout–ground bond + structure)
Bond length capacity and the structural capacity of grout plus bar (ASD 0.4f′c, 0.47fy). - Negative skin friction (downdrag)
Drag load on a pile from a settling layer (fill over soft clay) by the β method, and the maximum axial force at the… - Neutral plane, drag force and downdrag settlement (unified method)
Single pile through settling ground. The load curve (dead load plus accumulated negative friction from the top) and… - Pad footing
Square pad: bearing, flexural steel, one-way shear and punching shear. - Parallel seismic: unknown pile length
Fits straight lines to the first-arrival times above and below a trial break depth; the intersection, corrected for… - Pile axial capacity (layers, AS 2159 φg)
Shaft and base resistance through layered sand (SPT N) and clay (su), with the AS 2159 geotechnical reduction factor… - Pile cap (2/3/4 piles)
Truss-method tie force and steel, strut angle, pile load and column punching. - Pile cap for 2 to 9 piles
Standard pile cap layouts from 2 to 9 piles (line, triangle, square, square with centre pile, 2 × 3, hexagon with… - Pile capacity and settlement from CPT (LCPC method)
Pile designed directly from a cone penetration test, as in the GEO5 Pile CPT program. The equivalent base resistance… - Pile driving formulas (Hiley / Gates)
Ultimate resistance from hammer energy and set; check against required capacity. - Pile group efficiency & settlement
Group capacity from single-pile capacity with efficiency, block failure check in clay and group settlement from a… - Pile group loads (rigid cap, any layout)
Axial load in every pile of a vertical-pile group under axial load and biaxial moments, with compression and tension… - Pile group settlement & cap load distribution (interaction factors)
Each pile's head stiffness from Randolph & Wroth and the interaction factor α = ln(rm/s)/ln(rm/r0) between every pair… - Pile group settlement: equivalent raft and settlement ratio
Group of friction piles replaced by an equivalent raft at two-thirds of the embedded length, its plan size spread at 1… - Pile load–settlement curve: Fleming hyperbolic (CEMSET)
Predicts the full load–settlement curve of a single pile from its ultimate shaft and base capacities. Shaft load… - Pile set-up from restrike testing
Back-calculates the set-up factor A from end-of-drive and restrike capacities, then extrapolates the capacity at a… - Pile settlement: elastic and t-z
Head settlement of a single pile by the Randolph & Wroth closed form and by a load-transfer (t-z) analysis with… - Piled raft: load sharing and load–settlement (Randolph / Poulos)
Raft stiffness from a rigid plate on an elastic half-space, pile-group stiffness from Randolph & Wroth with a group… - Raft foundation
Corner pressures with two-way eccentricity, kern check, elastic and consolidation settlement. - Raked pile group (2D rigid cap)
Axial force in vertical and raked piles under a rigid cap carrying vertical load, horizontal load and moment, by the… - Rock-socketed pile
Socket shaft resistance from rock UCS, base resistance as a multiple of qu, geotechnical reduction factor φg. - Rock-socketed pile: capacity and settlement (Rowe & Armitage)
Bored pile socketed into rock below a soil overburden. Socket side resistance f = k√qu (Rowe & Armitage: k = 0.45 for… - Settlement on sand: Schmertmann (CPT)
Strain-influence settlement from CPT qc layers with E = 2.5qc (square) or 3.5qc (strip), depth and creep corrections. - Slab on elastic subgrade (Winkler plate, grillage)
Rectangular slab or raft on a Winkler subgrade (GEO5 Slab), analysed as a grillage of crossing slab strips with… - Slab on ground (Westergaard)
Flexural stress for interior, edge and corner wheel or post loads on a slab on grade. - Spread footing from CPT: bearing and settlement
Pad or strip footing designed directly from a CPT, as in GEO5 Spread Footing CPT. The equivalent cone resistance qce… - Static pile load test (Davisson)
Load–settlement curve with the elastic line and Davisson offset to find the failure load. - Static pile load test interpretation
Load–settlement readings: Davisson offset limit load, 10 % of diameter criterion and Chin's hyperbolic ultimate, then… - Strap (cantilever) footing
Exterior footing eccentric to a boundary column connected by a strap to an interior footing: reactions, footing areas… - Strip footing with eccentric load
Strip footing under a wall with moment: eccentricity, effective width B′, trapezoidal pressure and ultimate bearing on… - Thermal integrity profiling (TIP): effective diameter and cover
Converts the average temperature at an anomaly to an effective radius, estimates cover to the cage and the cage offset…
Retaining & slopes calculators
- Anti-slide (stabilising) piles in a slope
Force each pile must provide to raise the slope factor of safety, the moment and shear at the slip surface, and the… - Basal heave of an excavation in clay (Bjerrum–Eide)
FS = Nc su/(γH + q) with Skempton's Nc for the excavation geometry. - Braced excavation: apparent pressure & strut loads
Peck apparent pressure for sand, soft or stiff clay and strut loads by tributary area. - Cantilever retaining wall: L, inverted-T or counterfort, with reinforcement
Reinforced concrete retaining wall as an L-shape (no toe), inverted-T or counterfort wall. Stability by Rankine active… - Crib wall stability (Coulomb)
Treats the filled crib as a battered gravity block: Coulomb thrust on the inclined back, sliding, overturning… - Embedded retaining wall on elasto-plastic springs (staged, propped)
A sheet-pile, contiguous or secant wall modelled as a beam on springs that stay between active and passive limits… - Gabion gravity wall
Stepped gabion wall: weight from porosity, Coulomb active thrust with back-slope, sliding, overturning and base… - Ground anchor acceptance test
From the elastic extension between alignment and test load: apparent free length against the acceptance limits, tendon… - Ground anchor design
Strand count, fixed (bond) length, free length beyond the active wedge, lock-off and test loads, elongation and grout… - Infinite slope (static & pseudo-static)
Factor of safety for a long translational slide with seepage, seismic coefficient and the yield acceleration ky. - Lateral earth pressure
Active, passive or at-rest pressure diagram with water table, surcharge and cohesion. - Lateral pressure from surcharges (elastic)
Lateral pressure profile on a rigid wall from a line load (Terzaghi modified Boussinesq) and a strip load, with… - MSE ramp: back-to-back reinforced soil walls
Ramp of two facing MSE walls: height varying along the ramp, steel strips / geogrid / welded mesh, external stability… - MSE wall with steel strips
External sliding, overturning and bearing, plus Kr, maximum tension, pull-out and tension checks at every strip layer… - Planar failure with tension crack (Hoek & Bray)
Factor of safety of a planar slide with a water-filled tension crack, uplift on the plane and optional horizontal… - Prefabricated (segmental block) gravity wall
Dry-stacked concrete blocks set back at each course, as in GEO5 Prefab Wall and the Redi-Rock module. Coulomb active… - Reinforced soil wall (geogrid)
External sliding, overturning and bearing, plus reinforcement tension and pull-out at every layer. - Retaining wall stability
Cantilever wall: sliding, overturning, eccentricity and toe pressure. - Secant pile wall
Embedment and bending from the embedded-wall analysis, overlap and interlock thickness at the toe allowing for… - Seismic earth pressure (Mononobe–Okabe)
Static and seismic active coefficients, thrusts and overturning moment on a retaining wall. - Sheet pile / embedded wall
Embedment depth, anchor force and maximum bending moment for cantilever or single-anchored walls in granular soil… - Shotcrete facing (soil nail / anchored wall)
Flexure and punching-shear resistance of a reinforced shotcrete facing against the nail-head load, plus shotcrete… - Slope stability (Bishop / Fellenius, grid search)
Multi-layer slope with water table, crest surcharge and seismic coefficient. Searches a grid of centres for the… - Slope stability: Janbu simplified (slices)
Factor of safety for any (non-circular) slip surface entered as slices: width, mid-height, base inclination and… - Slope stability: Spencer & Morgenstern–Price with reinforcement and earthquake
Layered slope with a phreatic line, crest surcharge and a horizontal seismic coefficient. Finds the critical circle by… - Soil nail verification / proof test
Checks that the test reached the required multiple of the design load without pull-out or excessive creep, and… - Soil nail wall (simplified)
Nail forces from active pressure, pull-out beyond the failure plane and tendon tension for each nail row.
Ground engineering calculators
- 1D consolidation: multi-layer finite difference
Layered clay with different cv and mv, drained at the top, bottom or both. Solves the consolidation equation… - Basement uplift, buoyancy and base-slab design
Basement below the design high groundwater level: hydrostatic uplift against the permanent dead load (finished and… - Block sliding / toppling criteria
Mode of a block of width b and height h on a plane of dip ψ with friction φ: stable, sliding, toppling or both. - Circular shaft lining (ring compression)
Lateral earth and water pressure at the design depth, ring thrust and an ovalisation moment from non-uniform pressure… - Confined aquifer drawdown (Thiem & Cooper–Jacob)
Drawdown at a distance and time using Cooper–Jacob, and steady Thiem discharge for comparison. - Consolidation settlement
Primary settlement (NC or OC clay) and time to a degree of consolidation. - Convergence–confinement (circular tunnel)
Critical support pressure, plastic zone radius and wall displacement for a support pressure pi. - CPT liquefaction: FS profile, settlement and lateral spreading
Runs the full Boulanger & Idriss (2014) CPT procedure on every reading: Ic and fines content from Robertson's… - Dewatering: drawdown, pumping rate and neighbour settlement
Excavation treated as an equivalent large-diameter well in an unconfined or confined aquifer: radius of influence… - Dynamic compaction: depth of improvement
Depth of improvement, applied energy per unit area and print spacing check. - Excavation base uplift & piping
Uplift factor of safety of the clay plug over a confined aquifer and the exit-gradient piping check. - Footing on sand columns: bearing and settlement
Pad footing on a group of sand (or stone) columns in soft clay. The improved block gets a composite friction angle… - Geosynthetic-encased sand columns (GEC)
Sand or gravel columns wrapped in a geotextile sock for very soft clay under an embankment. Without encasement the… - Geotextile filter criteria
Retention (O95 ≤ B·D85) with B from Cu, permeability kg ≥ ks (critical ×10), and permittivity. - Granular filter design (Terzaghi)
Retention D15f/D85s ≤ 4–5 and permeability D15f/D15s ≥ 4–5 checks, with uniformity guide. - Hoek–Brown rock mass strength (GSI)
mb, s, a from GSI, mi and D; rock mass UCS, tensile strength, global strength and modulus. - Joint shear strength (Barton–Bandis)
Peak shear strength τ = σn tan(φr + JRC log10(JCS/σn)) and equivalent friction angle. - Liquefaction triggering (CPT)
CPT-based triggering with Ic screening, clean-sand equivalent Qtn,cs, FS profile, LPI and indicative settlement. - Liquefaction triggering (SPT)
Layer-by-layer CSR, CRR, factor of safety, LPI and post-liquefaction volumetric settlement from SPT blow counts and… - Packer permeability test (Lugeon)
Lugeon value of each stage using the effective pressure at the test section (gauge + water column − groundwater), and… - Point load index (rock)
Is and size-corrected Is(50) for diametral or axial/block tests, AS 1726 strength term and estimated UCS. - Prefabricated vertical drains
Radial consolidation with smear, time to target degree, triangular or square spacing. - Preloading with surcharge
Surcharge needed so that primary settlement under the permanent load is removed by a target time, with the degree of… - Pumping test analysis (Cooper–Jacob straight line)
Fits a straight line to late-time drawdown against log time in an observation well to give transmissivity and storage… - Q-system & support
Q = (RQD/Jn)(Jr/Ja)(Jw/SRF), equivalent dimension De = span/ESR, Q–RMR correlation and unsupported span. - Rigid inclusions (CMC) with a load transfer platform
Grid of rigid inclusions under an embankment or slab with a granular load-transfer platform. Arching by the Marston… - Rock bolt pattern for a loose block / wedge
Bolt load from suspending a loosened zone of height h over the bolt tributary area, with bolt length guidance. - Rock Mass Rating (RMR89)
Ratings for UCS, RQD and spacing from values, plus joint condition, groundwater and orientation adjustment; class and… - Rock slope kinematic analysis (planar, wedge, toppling)
Discontinuity sets mapped in a rock cut are tested against the slope face. Planar sliding needs a set dipping within… - Rock wedge stability (3-D, Hoek & Bray) with stereonet
Tetrahedral wedge formed by two discontinuities, the slope face and the upper ground surface. Geometry by plane… - Sand compaction piles
Replacement ratio, settlement reduction, composite shear strength, consolidation by radial drainage and sand… - Sand compaction piles for liquefaction mitigation
Loose sand densified by driving sand compaction piles. At each depth the SPT N gives the relative density and void… - Seismic hazard & base shear (AS 1170.4)
Hazard factor and return period to design spectrum for site classes Ae–Ee, natural period and base shear distributed… - Settlement monitoring: Asaoka and hyperbolic prediction
Predicts the final settlement from settlement-plate readings at a constant interval by two independent methods, and… - Site period & Vs30 from layers
Time-averaged shear-wave velocity over 30 m, average Vs of the soil column and fundamental site period. - Slug test (Hvorslev)
Fits ln(H/H0) against time to find the basic time lag T0 and the hydraulic conductivity of the screened zone. - Soil stabilisation binder spread rate
Binder spread rate and quantity from the target binder content, dry density and stabilised depth. - Stone columns (Priebe)
Area replacement ratio and basic settlement improvement factor for a stone column grid. - Tunnel face stability (Broms & Bennermark)
Stability ratio N = (σv − σT)/su and the support pressure needed to keep N at a target. - Tunnel lining & rock load
Overburden, lining hoop thrust and stress, ovalisation moment, and rock support pressure. - Tunnelling settlement trough (Peck)
Maximum surface settlement, trough width i = K z0 and settlement at an offset for a volume loss. - Well pumping: unconfined (Dupuit) & radius of influence
Discharge from a fully penetrating well in an unconfined aquifer with Sichardt's radius of influence. - Wick drains with preload: time–settlement (Hansbo)
Prefabricated vertical drains in a soft clay under a preload with surcharge. Equivalent drain diameter, influence…
Site investigation calculators
- Aggregate crushing value
Percentage passing 2.36 mm after crushing at 400 kN. - Atterberg limits & plasticity chart
Liquid limit from cone penetrometer or Casagrande points, PI, liquidity index and position on the plasticity chart. - Blast vibration (scaled distance)
Peak particle velocity from charge per delay and distance, and the maximum charge per delay for a PPV limit. - Blast vibration: site law regression and charge limits
Regresses monitored peak particle velocities against scaled distance to find the site constants, then the maximum… - Borehole log builder
Draws a borehole log from a layer table (base depth, soil type code, SPT N, description) with groundwater, and… - Brazilian tensile strength
Indirect tensile strength of rock discs σt = 2P/(π D t), averaged over the set. - Building damage assessment from ground movement
Bending and diagonal tensile strains in a wall from the deflection ratio and horizontal strain, the limiting tensile… - Bulk density by wax coating
Bulk and dry density of an irregular lump from waxed mass in air and in water. - California Bearing Ratio (lab)
Load–penetration curve to CBR at 2.5 and 5.0 mm, with swell and pavement subgrade notes. - CBR soaked swell & moulding conditions
Swell during soaking, moulding density ratio and moisture ratio for a CBR specimen. - Coefficient of consolidation (root-time & log-time)
cv from Taylor's t90 and Casagrande's t50, with permeability from k = cv·mv·γw. - Collapse potential (oedometer)
Collapse potential from the strain on wetting at constant stress, with the usual severity classes. - Compaction curve (standard / modified)
Moisture–density points to MDD and OMC with zero-air-voids and 80 % saturation lines, plus field density ratio. - CPT interpretation (Robertson SBTn)
Normalised cone resistance and friction ratio, Ic, soil behaviour type plotted on the Robertson chart and as a profile. - CPTu dissipation test: ch and kh
Horizontal coefficient of consolidation from the time to 50 % dissipation, with an optional estimate of horizontal… - DCP to CBR
Penetration per blow by layer and estimated in-situ CBR, plotted with depth. - Density index (max/min dry density)
Density index of a sand from its maximum and minimum index densities and the field dry density. - Direct shear test
Peak (and residual) failure envelopes from shear box results. - Double hydrometer dispersion ratio
Percent dispersion from the fraction finer than 5 µm with and without dispersant and mechanical agitation. - Downhole seismic: interval Vs, Vs30 and site class
Corrects slant travel times to vertical, computes interval shear-wave velocities, Vs30 and the site period of the soil… - Emerson class number (dispersion)
Decision tree for the Emerson class (1–8) from observed slaking, dispersion and swelling of soil aggregates. - Field density: core cutter
Bulk and dry density from a driven core cutter, with relative compaction against the laboratory MDD. - Field density: sand replacement
Hole volume from calibrated sand, then bulk density, dry density and relative compaction. - Fines content by washing
Percentage finer than 75 µm from the dry mass before and after washing plus dry sieving of the residue. - Flakiness index
Flakiness index from the flaky mass in each size fraction. - Flat dilatometer (DMT) data reduction
Corrects the A and B readings, then gives the intermediate parameters ID, KD, ED, soil description, constrained… - Free swell & swell pressure (oedometer)
Free swell strain under seating load and swell pressure from the constant-volume or load-back method. - Hydrometer analysis
Fine-fraction grading from hydrometer readings: particle diameter by Stokes' law and percent finer. - Inclinometer: displacement profile and rate
From initial and current deviation readings per probe interval (A-axis), the incremental and cumulative displacement… - Linear shrinkage
Linear shrinkage of a soil bar dried in a 250 mm mould, with a rough plasticity index indication. - Liquid limit: Casagrande cup
Flow curve (w against log N) by least squares; LL at 25 blows and the flow index. - Liquid limit: cone penetrometer
Linear fit of moisture content against cone penetration; the liquid limit is w at 20 mm penetration. - Liquid limit: one-point method
LL from a single Casagrande reading using LL = wN (N/25)^0.121, valid for 20–30 blows. - Los Angeles abrasion loss
LA abrasion loss of a coarse aggregate grading after 500 revolutions. - Ménard pressuremeter: modulus, bearing and settlement
Ménard modulus from two points on the pseudo-elastic part of the test curve, net limit pressure, soil class from… - Moisture content (oven drying)
Moisture content of several specimens from tin masses, with mean, range and repeatability check. - Moisture, density & phase relations
Bulk and dry density, void ratio, porosity, saturation and field density ratio, with a three-phase diagram. - Nuclear gauge density lot assessment
Lot of nuclear gauge tests: dry density, relative compaction, characteristic value (mean − k·s) and moisture ratio. - Oedometer consolidation test
Lab sheet: e–log σ' curve, Cc, Cr, Casagrande preconsolidation pressure, mv per stage and cv by Taylor's root-time… - Organic content (loss on ignition)
Loss on ignition from crucible masses, with the AS 1726 organic description. - Particle density & water absorption (coarse aggregate)
Oven-dry, SSD and apparent particle densities and water absorption from the basket method. - Particle size distribution
Sieve masses to % passing, grading curve, D10/D30/D60, Cu, Cc and a USCS group symbol. - Permeability (constant / falling head)
Hydraulic conductivity from constant- or falling-head tests, corrected to 20 °C. - Permeability: flexible-wall (triaxial)
Hydraulic conductivity from steady inflow/outflow under a back-pressure difference, temperature corrected to 20 °C. - Plastic limit & consistency indices
PL from repeat threads, PI, liquidity and consistency index, activity and plasticity chart class (A-line). - Plate load test
Pressure–settlement curve to deformation modulus and modulus of subgrade reaction. - Pocket penetrometer & consistency
Converts pocket penetrometer readings (≈ qu) to su and the AS 1726 consistency term. - Relative compaction & moisture variation
Density ratio and moisture variation from field and laboratory results against a specification window. - Residual strength: ring shear
Residual friction angle from a regression through the origin and a free-intercept fit. - Resistivity sounding (Wenner array)
Apparent resistivity for each electrode spacing from the measured resistance, the range and trend with depth, and an… - Rock uniaxial compressive strength & modulus
UCS of a rock core with the L/D correction, tangent modulus at 50% and the ISRM strength term. - Sand equivalent
Sand equivalent from clay and sand readings in the graduated cylinder (mean of trials). - Seismic refraction: two layers, forward and reverse shots
Least-squares lines for the direct and head-wave arrivals of a forward and a reverse shot give V1, the apparent up… - Shrink–swell index & AS 2870 site class
Iss from swell and shrink strains, characteristic surface movement ys for a triangular suction profile, and site class. - Shrinkage limit & shrinkage ratio
Shrinkage limit from wet and dry pat volume and mass, with shrinkage ratio and volumetric shrinkage. - Slake durability index
Second-cycle slake durability index and Gamble durability class. - Soil aggressivity to buried concrete & steel
Exposure classification for concrete and steel piles from pH, sulfate, chloride and resistivity. Thresholds… - Specific gravity (pycnometer)
Two-trial lab sheet for soil particle density with temperature correction to 20 °C and repeatability check. - SPT corrections & correlations
Raw N to N60 and (N1)60 with energy, rod, borehole and overburden corrections, and common correlations, plotted with… - Stress paths (MIT p′–q) and strength fit
Total and effective stress paths from triaxial data, with the Kf line fitted to give c′ and φ′. - Ten percent fines value (wet/dry strength)
Load giving 10% fines from a test at x kN producing y% fines: F = 14x/(y + 4); wet/dry variation. - Triaxial test (UU / CU / CD)
Mohr circles and failure envelope from triaxial specimens: su for UU, c′ and φ′ for CU (with pore pressure) or CD. - Unconfined compression test
Stress–strain with area correction, peak qu, su = qu/2 and E50 secant modulus. - Vane shear (lab / field)
Undrained strength from peak and remoulded torque, sensitivity and Bjerrum's plasticity correction.
Pavements & traffic calculators
- Asphalt overlay from FWD deflections
Falling-weight deflectometer bowls at each test point give the surface modulus (from D0), the subgrade modulus (from… - Asphalt volumetrics (Marshall)
Air voids, VMA and VFA from bulk and maximum densities, with Marshall stability and flow checks. - Car park layout (AS/NZS 2890.1) and accessible spaces
Rectangular open-air car park laid out with 90° bays in double-loaded modules (bay + aisle + bay) across the site… - Concrete (rigid) pavement thickness
Plain concrete pavement or hardstand under a design axle. The subgrade reaction k comes from the CBR and is lifted by… - Design traffic (ESA) for pavements
Cumulative heavy vehicle axle groups and ESAs over the design period with compound growth. - Flexible pavement: mechanistic check (CIRCLY-style)
Mechanistic check of a flexible pavement under the Austroads Standard Axle. Layers are transformed by Odemark's… - Granular pavement thickness (thin surfacing)
Total granular cover above the subgrade from CBR and design traffic: t = [219 − 211 log CBR + 58 (log CBR)²]… - Horizontal curve: radius, superelevation, transition, sight clearance
Minimum radius for the design speed from maximum superelevation and side friction; the side friction demanded on the… - Lane closure: tapers, buffer, signs and queue (TTM)
Single-lane closure on a multilane road. The merge and shoulder taper lengths follow from the approach speed and lane… - Mechanistic pavement criteria (subgrade & asphalt)
Allowable repetitions from subgrade vertical strain N = (9300/µε)⁷ and asphalt fatigue N = RF[6918(0.856Vb +… - Road capacity and level of service (multilane / motorway)
Basic motorway or multilane road segment. Demand is converted to passenger cars per hour per lane (peak-hour factor… - Roundabout entry capacity and delay
Each approach enters against the circulating flow in front of it. Entry capacity follows Tanner's gap-acceptance… - Signalised intersection: cycle, green splits and delay
Fixed-time signals with one critical movement per phase. Flow ratios y = q/s give the intersection flow ratio Y and… - Stopping sight distance and vertical curves
Stopping sight distance for the design speed, reaction time and deceleration, corrected for the grade; the crest curve… - Weighted plasticity index & base suitability
Weighted plasticity index and plasticity modulus for unbound pavement material checks.
Hydraulics & drainage calculators
- Culvert outlet control headwater
Headwater for a full-flowing culvert in outlet control: HW = H + ho − L S with entrance, friction and exit losses. - Flood freeboard, hazard and loads on a building
For a building site in a flood-prone area: depth and depth × velocity, the ARR 2019 combined hazard category (H1–H6)… - Grassed swale and bioretention basin
A trapezoidal grassed swale conveying the treatment flow and the major flow to a bioretention basin. Normal depths and… - Hydraulic jump
Sequent depth, energy loss and jump length for a rectangular channel. - Kerb and channel flow spread and kerb inlets
Flow in a kerb and channel with a depressed gutter: spread T from Izzard's equation with the composite-gutter ratio Eo… - On-site detention storage (triangular hydrographs)
Storage from post-development inflow and permissible site discharge using the triangular-hydrograph approximation V =… - Open channel flow (Manning)
Discharge, velocity and Froude number for a trapezoidal channel at a given depth. - Orifice outlet
Discharge of an orifice under head and the orifice size for a target flow. - Partially full pipe (Manning)
Flow area, wetted perimeter, discharge and velocity at a given depth ratio in a circular pipe, and full-bore capacity. - Pier scour (CSU / HEC-18)
Local scour depth ys = 2.0 K1 K2 K3 a (y1/a)^0.35 Fr^0.43. - Pressure pipe head loss (Darcy & Hazen–Williams)
Friction factor, head loss by Darcy–Weisbach and Hazen–Williams, and velocity for a full pressure pipe. - Rational method peak flow
Time of concentration (Bransby-Williams), peak flow for a design intensity and catchment. - Riprap sizing (Isbash)
Stone diameter for a design velocity: d = V²/(2g C²(Gs − 1)), stone mass and layer thickness. - Stormwater pipe network (QUDM rational method)
Minor drainage network laid out as pits draining to a downstream pit (0 = outlet), listed upstream first. For each… - Stream & debris force on a pier
Drag force from flow on the pier and on a debris mat, with the resultant height for overturning. - Weir discharge (sharp & broad crested)
Rectangular sharp-crested weir Q = Cd(2/3)√(2g) b H^1.5 and broad-crested Q = 1.705 b H^1.5.
Bridges calculators
- Box culvert
Single-cell culvert: earth and surcharge loads, corner and mid-span moments. - Box girder section
Single-cell box: area, centroid, I, section moduli and fibre stresses, with optional prestress. - Bridge abutment: stability and stem design
Cantilever abutment carrying the deck reactions on its bearing shelf, with earth pressure from the approach fill and a… - Deck expansion joint movement
Joint movement from temperature range, shrinkage and creep shortening over the expansion length; gap at installation. - Elastomeric bearing (Method A)
Shape factor, compressive stress limit 1.0·G·S (≤ 7 MPa), shear deformation limit Δs ≤ hrt/2 and rotation sense check. - Girder load distribution (lever rule)
Share of a wheel line pair to an exterior girder by the lever rule with deck cantilever. - Influence lines and moving loads
Influence lines for reaction, shear and moment at a chosen section, and the critical position of an axle train for the… - SM1600 bridge girder: moving load, envelope, girder check
Simply supported bridge span under the AS 5100.2 SM1600 family. The M1600 vehicle (four tri-axle groups of 3 × 120 kN…
Analysis & loading calculators
- Beam on elastic foundation (Winkler)
Deflection, bending moment and contact pressure under a point load on a long beam or strip footing resting on Winkler… - Continuous beam (stiffness method)
Any number of spans with UDLs; exact BMD, SFD, reactions and deflected shape. End fixity selectable. - Cyclonic wind: roof uplift and tie-down chain
Roof uplift on a house or shed in any wind region, including the cyclonic Regions C and D. Regional speed VR = F(a −… - Dead load build-up and design loads
List the layers of a floor or roof build-up, either as a thickness with a unit weight or as an area load directly. The… - Dynamic amplification (SDOF, harmonic)
Dynamic amplification and force transmissibility for a damped single-degree-of-freedom system. - Earthquake: equivalent static storey forces (AS 1170.4)
Fundamental period, spectral shape factor for the site class, base shear and its distribution to storeys with the… - Euler buckling (end conditions)
Critical buckling load and stress for the four classic end conditions. - Fatigue damage (Miner's rule)
Cycles to failure for each stress range block from N = 2×10⁶ (ff/fr)³ (m = 3) and the cumulative damage sum. - Frame analysis (any 2D structure)
Define nodes, members (UB/UC or RC sections), supports and loads for any plane frame, beam or truss. Get bending… - Gravity load take-down
Column axial load storey by storey with dead, live, live-load area reduction and ULS/SLS combinations. - Impact load from a dropped mass
Equivalent static force from a mass dropped onto an elastic member: F = W(1 + √(1 + 2h/δst)). - Live load area reduction
Reduction factor ψa = 0.3 + 3/√A for tributary areas over 20 m² (not for assembly, storage or Q > 5 kPa). - Load combinations (AS/NZS 1170.0)
Strength and serviceability combinations for any action effect (moment, shear, axial or reaction) from dead, imposed… - Machine foundation (vertical mode)
Vertical stiffness and damping of a rigid circular base, natural frequency and frequency ratio against the operating… - Mohr circle explorer
Principal stresses, maximum shear and the stresses on any plane. Change θ and watch the point move around the circle… - Section properties: arbitrary polygon
Area, centroid, second moments, product of inertia, principal axes and section moduli for any polygon given by its… - Snow loads with drifting at a roof step
Roof snow load for alpine and sub-alpine sites. Balanced and unbalanced shape coefficients for mono- and duo-pitch… - Strain rosette (0/45/90)
Principal strains, direction and principal stresses (plane stress) from a 0°/45°/90° rosette. - Thermal movement & restraint stress
Free thermal movement, fully restrained stress and force, and movement-joint spacing for an allowable movement. - Thick-walled cylinder (Lamé)
Hoop and radial stresses at the bore and outside surface under internal and external pressure, with von Mises at the… - Torsion of thin-walled closed sections (Bredt)
Shear flow q = T/(2Ao), wall shear stresses and torsion constant J = 4Ao²/∮ds/t for a rectangular box. - Truss solver (method of joints)
Pratt, Howe or Warren truss with panel loads: every member force, colour-coded tension (blue) and compression (red). - Two-way slab load to beams
Slab load to supporting beams by 45° lines: triangular load on short beams, trapezoidal on long beams, and equivalent… - Wind actions (AS/NZS 1170.2 simplified)
Site wind speed, design pressure and net wall and roof pressures for an enclosed rectangular building. - Wind pressure on cladding & fixings
Design pressure for a cladding element from Vdes, external and internal coefficients, area reduction and local… - Wind: site wind speed and building pressures (AS/NZS 1170.2)
Regional and site wind speed with terrain, shielding and topographic multipliers, design pressure, wall and roof…
Temporary works & site calculators
- Bored pile: concrete volume, cage and pour
Concrete and reinforcement quantities for a bored pile: theoretical and overbreak volume, trucks, tremie pour time… - Concrete formwork pressure (CIRIA R108)
Lateral pressure of fresh concrete on wall or column formwork from the rate of rise, temperature, form height and mix… - Crawler crane lift check (radius, capacity, ground bearing)
Checks a crawler-crane lift against a load chart (radius vs rated capacity, interpolated), adds hook block and… - Driven pile: Hiley formula (set, capacity, blows per 250 mm)
Relates the final set per blow to the pile resistance for a drop or hydraulic hammer: R = ηh·W·h·ηb/(s + c/2), with… - Lifting lug (padeye) plate check
A plate padeye with a pin hole: bearing on the plate, net-section tension across the hole, shear tear-out to the top… - Mobile crane outrigger pad / crane mat
Worst outrigger load for a mobile crane slewing over a corner (crane + load share plus the load moment over the… - Piling rig working platform (BRE 470)
Granular working platform thickness for a tracked piling rig on a cohesive subgrade by the BRE 470 punching-shear… - Precast pile lifting & pitching moments
A square precast concrete pile lifted horizontally at two points (0.207L from each end, equal hogging and sagging) and… - Spreader beam (lifting) — CHS strut, AS 4100
A tubular spreader carrying a load from two lower slings with a two-leg upper sling to the hook. Sling geometry gives… - Strutted trench: Peck apparent pressure & strut loads
A braced trench with sheeting and struts at chosen levels: Peck's apparent pressure envelope (0.65KaγH for sand; soft… - Temporary cut batter: safe height (Culmann)
The critical height of a temporary cut by Culmann's planar wedge for a soil with cohesion and friction, the factor of…
Utilities calculators
- Coordinates: MGA2020 ↔ latitude / longitude
Converts geographic coordinates (latitude, longitude on GDA2020) to Map Grid of Australia easting and northing in the… - Unit converter
Length, force, pressure, moment, density, area and volume.
Construction & estimating calculators
- Aggregate and base-course tonnage
Tonnes of road base, crushed rock or sand for an area and compacted thickness, with loose volume, truck loads and cost. - Asphalt & pavement
Asphalt tonnes, tack coat and base course quantities and cost. - Bar schedule & rebar weight
Reinforcement mass by bar mark, totals by diameter and tonnage to order. - BOQ builder (bill of quantities)
Add line items with quantities and rates, apply preliminaries, overhead & profit, contingency and GST; export CSV or… - Brickwork & blockwork
Bricks or blocks, mortar, cement bags and sand for a wall, with openings, waste and cost. - Cash-flow S-curve
Monthly spend and cumulative S-curve from a total budget and profile shape, with peak month. - Compaction production and lifts
Number of lifts, roller output and days to place and compact a fill platform. - Concrete materials estimate
Cement bags, sand, aggregate and water for site-mixed concrete by ratio, with wastage. - Concrete maturity (strength in place)
Temperature–time factor and equivalent age from logged temperatures, and estimated in-place strength from a… - Concrete mix design (ACI 211.1)
Batch quantities per m³ (water, cement, coarse and fine aggregate) by the ACI absolute-volume method. - Concrete pour planner
Number of agitator trucks, trucks needed in rotation, pour duration, finish time and cost for a concrete pour. - Concrete volumes & cost
Volumes for footings, slabs, beams and columns, order quantity rounded to 0.2 m³, trucks and cost. - Cost escalation
Escalate a base estimate by a compound annual rate or by the ratio of cost indices, including mid-construction… - Earthworks cut & fill
Volumes from cross-section areas, loose and compacted volumes, truck loads and a mass-haul diagram. - Excavation dewatering estimate
Inflow to a dewatered excavation treated as an equivalent large-diameter well in an unconfined aquifer, with pump power. - Excavation, cart-away & disposal
Excavated bank volume with batters, bulking, backfill retained, truck loads, tonnes to tip and cost. - Flooring (timber / vinyl / laminate)
Boxes of boards or planks, underlay rolls, skirting and cost. - Formwork contact area
Formwork area for slabs, beams, columns and footing edges, ply sheets allowing for re-use, and cost. - Labour productivity & crew cost
Man-hours, crew days, labour cost with on-costs, plant cost and unit rate for an activity. - Painting
Litres and tins of paint and primer, with labour. - Plant fuel and CO₂
Diesel use, cost and CO₂ for a plant fleet from rated power, load factor and specific fuel consumption. - Plasterboard (walls & ceilings)
Sheets, fixings, jointing compound and tape for walls and ceilings. - Plastering & rendering
Render or plaster quantities: wet volume, cement bags, sand and cost. - Rebar cutting length and laps
Cutting length for straight, L, U or closed-link bars with bend deductions and hooks, the laps needed for long runs… - Reinforcement quantities & cost
Steel tonnage from a kg/m³ ratio or a bar list, with laps and waste, supply and fix cost. - Roof sheeting & battens
Gable roof area from plan and pitch, sheet count and length, battens, screws and cost. - Scaffold take-off (modular)
Component count for a single-run modular scaffold, with tie count and hire cost. - Tiling
Tiles, boxes, adhesive and grout for a floor or wall. - Timber wall framing take-off
Lineal metres of studs, plates, noggins and jamb studs for a list of walls. - Trench shoring take-off
Panels, strut rows and struts for a strutted trench, with excavation volume and hire cost. - Truck and loader fleet balance
Truck cycle time, trucks needed to keep the loader busy, fleet production and hours to move a volume.
Project controls calculators
- Gantt chart & CPM schedule
Add tasks, durations and dependencies; see the critical path, drag bars, export CSV or PNG. Saved in your browser.