To address the insufficient tensile strength of composite fan blade dovetail roots

a layup design strategy was developed. A finite element model of composite interlayer structures with resin pocket defects was developed to systematically analyze the effect of drop layer angles on structural strength. Additionally

a finite element model of composite dovetails was established to collect stress data of resin pockets in variable-thickness regions

enabling the optimization of layup design parameters based on the analysis. Results show that the interlayer structure strength increases by 28% at drop layer angles of 45° and 90° compared to the 0° condition. Following optimization

the maximum stress in dovetail resin pockets decreased from 121.57 MPa to 50.50 MPa

with overall strain values reduced and stress dispersion and resistance to strain concentration significantly enhanced in critical areas. This study provides a theoretical basis for the design of composite dovetail structures and offers engineering guidance for improving their stability and reliability under real-world operating conditions.