Sensitivity

STATIC PROBLEMS
Notes
Direct Differentiation Method (DDM)
Linear Static DDM
Adjoint Method
Nonlinear Static DDM
Bouc-Wen Material Derivatives
Examples
Sensitivity of Cantilevered Beam Displacement
DYNAMIC PROBLEMS
Notes
Linear Dynamic DDM
Nonlinear Dynamic DDM
Rayleigh Damping Derivatives
Modal Damping Derivatives
Eigenvalue Derivatives

Although I love the topic of sensitivity analysis, and wish the DDM was in more widespread use, some of the notes posted above are a bit sloppy. I am currently writing a free online textbook on the topic; I will post it here as soon as it is ready in the fall of 2026.  In the meantime, direct differentiation for the calculation of first- and second-order response sensitivities for linear, nonlinear, static, and dynamic analysis is comprehensively implemented in the Python code G2 posted on the Finite Elements page.