A guide to BS 7910:2019 Annex P: it explains the physical meaning of the reference stress Ο_ref and the reference-stress method, the equivalence of Ο_ref and the limit load P_L, how it gives the FAD horizontal axis L_r, the general framework and net-section degradation, the plastic cut-off L_r,max and flow stress, and the calculation steps β with original diagrams and a live worked example.
A guide to BS 7910:2019 Annex M: starting from crack-tip stress singularity, it explains the physical meaning of the stress intensity factor K_I, the general Annex M framework and its correction factors, the semi-elliptical surface-crack solution and evaluation points, the weld-toe magnification factor Mk, and the full calculation steps β with original diagrams and a live worked example.
A guide to BS 7910:2019 Clause 7 fracture assessment: starting from the two failure modes, it uses a single Failure Assessment Diagram (FAD) to tie together the fracture-mechanics principle, the K_I / Ο_ref / K_r / L_r calculation chain, and the standard assessment steps β with original diagrams and a live worked example.