Free Web Tool · FHWA NHI-10-024

MSE Wall Internal Stability

Per-layer reinforcement tension Tmax and pullout-resistance ratio FS_po per FHWA NHI-10-024 simplified method (steel inextensible, single-tier wall).

Input

Results

Ka = tan²(45 − φ/2)
σh at base (γH·Ka + q·Ka)
Tmax per layer (max σh·Sv)
Pullout resistance Pr = α·F*·σv·b·2·Le
FS pullout = Pr / Tmax
Required strip thickness (yield)
Method

Tmax_i = σh_i · Sv where σh = Kr·σv + Δσh (here Kr ≈ Ka). σv = γ·z + q. Pullout: Pr = α·F*·σv·b·2·Le. Yield: t_req = Tmax / (b·Fy/1000) plus sacrificial allowance. FS_po ≥ 1.5 typical.