Building tools where
structures meet software
I write about computational structural engineering, finite element methods, and the applications I build to make structural analysis more accessible, visual, and open.
Latest writing
From the notebook
Saola: A Grasshopper Plugin Built on ETABSharp
ETABSharp made ETABS automation testable and composable. Saola takes that one step further — bringing it into Grasshopper so structural engineers can build parametric ETABS workflows without leaving the canvas.
Read article →The Stiffness Matrix from First Principles
Where does the element stiffness matrix actually come from? A full derivation from virtual work, through shape functions, to the 12×12 frame element matrix you use every day.
Talking to ETABS in Natural Language: ETABSSharp + MCP
I built an MCP server on top of ETABSSharp that lets AI assistants query, modify, and run analysis on ETABS models through plain English. Here's how it works.
Building ETABSharp: A C# Wrapper for the ETABS API
The raw ETABS API is verbose and weakly typed. Here's how I designed a fluent C# wrapper that makes structural automation actually enjoyable to write and get help from LLM.
Open tools
Engineering calculators
Beam Calculator
Simply supported, fixed-end, cantilever. Shear, moment, and deflection diagrams — live as you type.
Open tool →Section Properties
I, A, Z, S, r for standard and custom cross-sections. Export results to JSON.
Open tool →Column Buckling
Euler and Johnson curves with automatic method selection based on slenderness ratio.
Open tool →About
Thanh Tu Do
Structural Eng. & App Developer
I'm a structural engineer who writes software. I work on high-rise buildings and long-span structures, and I build the tools I wish existed — browser-based calculators, ETABS automations, Rhino/grasshopper plugins, open structural solvers.
This site documents that work. The writing spans 3D complex modeling, computational methods, and the software architecture behind the tools.