Shear-Lag Fiber Pull-Out: Stress & Shear Profiles (2D)

A 2D companion to the fiber pull-out test, built directly from the shear-lag (Cox/Kelly) equilibrium differential equation rather than a flattened 3D scene: the fiber-stress and interfacial-shear-stress profiles along the embedded length are solved in closed form for the current debond length, redrawn live as the debond front advances, and integrated to produce the force-displacement curve. Because the debond-propagation force is solved from the actual profile — not assumed constant — it rises as the bonded region shrinks, a real stress-concentration effect near full debond that a flat-plateau approximation misses. Choose a fiber, set the embedded length and interfacial shear strength, and run the pull test to see elastic loading, shear-lag-governed debonding, and frictional slide-out (or fiber fracture) play out together with the underlying stress fields.