Diaphragm + Shear Wall Detailer

Distribute a storey lateral shear V to the shear walls — by rigid-diaphragm analysis (center of rigidity, direct + torsional shear from eccentricity) or by flexible-diaphragm tributary distribution — then get each wall's force & unit shear and the diaphragm chord / collector force, with a plan diagram.

⭐ Free to design · Balance … EP

⚠️ Educational tool — verify against NSCP 2015 / ASCE 7 §12. Rigid-diaphragm torsion uses walls resisting in the load direction only (ignores transverse-wall contribution to J — conservative for those walls). Add accidental torsion (±5% of the plan dimension) and amplification A_x where required, and detail chords/collectors/connections to the code.

① Diaphragm idealisation

Storey shear V (kN)

Diaphragm span L (m)

Diaphragm depth B (m)

Load coord. x_cm (m) (rigid)

Wall coordinate x is measured along the span L from one end (0 → L). The chord force uses M = V·L/8 (uniform diaphragm load) and the depth B as the lever arm.

② Shear walls (resisting in the V direction)

Name

Rigidity R

x (m)

Length L_w (m)

Rigidity R is relative (used in rigid mode). In flexible mode walls are loaded by tributary width from their positions (R ignored).

🧱 Wall force distribution

—

Center of rigidity x_cr

—

Eccentricity e

—

Σ R_id_i² (J)

—

Max wall force

—

Max unit shear

—

Chord / collector C

—

Wall force table

Diaphragm + Shear Wall Detailer

① Diaphragm idealisation

② Shear walls (resisting in the V direction)

🧱 Wall force distribution

Wall force table

Worked solution