Roof Joint Wraps R1.

Research record

The detail behind
the study.

Source-linked work for this revision. Reported checks describe the stated model or test; physical qualification and applicability to the current retrofit remain separate.

Preliminary opening-frame reinforcement

The assembly contains nine frame members, six external reinforcement solids and six separate bondline volumes. The overwrap follows each T junction and leaves the branch ends open. STEP keeps all 21 solids separate for inspection.

Initial engineering choices: 6 mm reinforcement, 0.5 mm bondline and 100 mm extension beyond the member face. These are not strength-sized or approved laminate dimensions. They establish actual space consumption and assembly interfaces for further design.

The conservative rectangular opening reduces from 944 × 560 mm to 931 × 547 mm. Reinforcement also projects 6.5 mm above and below the original members, which must be accommodated by roof skin and bearing details. The former opening dimension must not be quoted as the finished clear opening.

Manufacturing direction is external secondary-bonded reinforcement applied while the assembled frame is accessible, before closing the roof skin. This is a direction for process development, not a complete work instruction. Reentrant corner fillets, ply orientations/drop-offs, drape, adhesive selection, surface preparation, bondline control and cure remain unresolved. Square corners in this first envelope are not acceptable finished ply paths by implication.

The geometry generator checks single solids, stock interference, joint-to-joint interference, conservative opening clearance and STEP body preservation. These checks do not establish shear/bending/torsion interaction, peel strength, fatigue, environmental durability or manufacturing acceptance. Joint loads are recorded separately in the roof-joints-r1 package.