Chapter 2: Stiffness Method Procedures
Chapter 3: Continuum (2D/3D) Elements
CST Beam Analysis
Auto-mesh a beam into Constant Strain Triangle elements. Visualize the stiffness matrix, displacements, strains, and von Mises stress with adjustable mesh density.
Section 3.2Interactive Element Explorer
Drag element nodes to prescribe displacements and watch strain and stress update in real time. See displacement arrows, contours, and the deformed shape.
Section 3.2Why This Q4 Field Is Not OK
Explore why certain displacement fields violate completeness or compatibility requirements for the Q4 quadrilateral element.
Section 3.2Inter-Element Compatibility
Compare linear, quadratic, and higher-order shape functions along shared element edges to see when displacement fields stay compatible across neighbors.
Section 3.2Isoparametric Mapping
Drag physical nodes to see how the master element maps to general quadrilaterals. Visualize the Jacobian and isoparametric transformation process.
Section 3.38- & 9-Node Isoparametric Elements
Switch between Q8 serendipity and Q9 Lagrangian elements. Drag mid-side and centre nodes to bend edges into parabolas and watch the Jacobian respond.
Section 3.5Plate with Hole — Q8 Plane Stress
Full FEM example: rectangular plate with a circular hole, bottom fixed, non-uniform traction on top. Auto-meshed with 4-petal Q8 serendipity elements; view stresses, strains, and deformed shape.
Section 3.5Numerical Integration Playground
Midpoint, Simpson, and Gauss–Legendre side by side. Drag sample points to watch moment-matching gauges light up, run a physics-style optimizer that snaps the points to the Gauss roots, or race Monte-Carlo “rain” against a 2-point Gauss rule.
Section 3.6