ContinuaX: an agent-driven finite element program for structures, its solution methods and its calibration in static and dynamic analysis

ContinuaX is a finite element program for structures, written in Rust, that an engi-neer drives through a window and an AI agent drives through the Model ContextProtocol (MCP), both acting on the same model at the same time. It offers solids,shells, beams, seven material models and static, buckling, frequency, response-spectrum and implicit dynamic analysis through 34 MCP tools, and it solves onthe CPU or on an NVIDIA GPU. Every calibration case was built and solvedthrough the MCP tools. The NAFEMS LE1 membrane differs from its referenceby +0.26 %, the LE10 thick plate converges to within 1 % on 312,000 equationson a rented GPU, and five shell and solid benchmarks agree with their referenceswithin 1.5 %. The NAFEMS FV12 frequencies agree within 1.16 %, the error ofan oscillator falls with the square of the time step to 0.009 %, and Euler’s bucklingloads are reproduced within 1.1 %. In four case studies against measurements, themasonry modulus of a 70 m brick stupa calibrated to its measured first frequencyof 1.388 Hz is 1.08 GPa, an IPE160 beam matches the measured stiffness and yieldmoment but exceeds the ultimate moment because local buckling is not modelled,a shear-critical reinforced concrete beam reaches 1.08 times its measured strength,and a prestressed box girder places the neutral axis correctly but is 0.73 times asstiff as the test. Shells carry no geometric stiffness yet, beams have no warping,and there is no geometric nonlinearity.