Builds the horizontal acceleration response spectrum S_a(T) for 15 seismic design codes worldwide, with overlay comparison of multiple codes / parameter sets on one chart.

• EC8 Type 1/2, NTC-18, France NA
• ASCE 7-16/7-22, ASCE 41-17, UBC-1997, NBCC 2015
• NZS 1170.5, IS 1893:2016, TBEC/TBDY-2018
• GB 50011-2010, NCSE-02, NTE E.030:2016, Iran 2800
• Elastic & design spectra · multi-curve overlay

Complete geometric, section and design resistance properties for standard rolled steel sections (IPE, HEA, HEB, HEM) per EC3. Includes cross-section classification and unit switching between cm and mm.

• Full section geometry & inertia properties
• Torsional & warping constants
• Cross-section classification (§5.5)
• N_pl,Rd, V_pl,Rd, M_el,Rd, M_pl,Rd
• Unit toggle: cm ↔ mm

ULS cross-section and member stability checks for standard rolled steel sections (IPE, HEA, HEB, HEM). Supports multiple load combinations with full utilisation factor breakdown.

• 22 checks per combination (§6.2 & §6.3)
• Flexural, torsional & LTB buckling
• Interaction checks (Annex A & B)
• Section optimizer · CSV export
• Paste load combinations from Excel

Cantilever retaining wall design using Rankine earth pressure theory. Covers full stability analysis and reinforced concrete structural design with a live dimensioned wall sketch.

• Rankine Ka / Kp earth pressure
• Overturning, sliding & bearing checks
• RC design: stem, heel & toe (EC2)
• Dynamic cross-section canvas sketch
• Surcharge & groundwater options

Converts survey point coordinates from the EGSA87 (GGRS87) projected grid to WGS84 geographic coordinates. Results in decimal degrees and DMS, with an interactive map and spatial statistics.

• Inverse TM projection & Helmert datum shift
• Decimal degrees & DMS output
• Interactive Leaflet map (OSM & satellite)
• Haversine path length & polygon area
• Excel import & export · clipboard paste