Expert Guide

Babu

Structural Design Helpers

Seismic Base Shear Estimator (IS 1893)

Quality Inspector

Kaka

Estimate earthquake design force.

📐 Formula & Method

Vb = Ah × W, where Ah = (Z/2) × (I/R) × (Sa/g). Sa/g is usually 2.5 for stiff soil.

Vb = (Z/2 × I/R × 2.5) × W

📋 Worked Example

5000kN weight, Zone III, I=1, R=3:
• Vb = (0.08 × 1/3 × 2.5) × 5000 ≈ 333 kN

❓ Frequently Asked Questions

Which zone is Delhi in?

Delhi falls in Zone IV (High Risk Zone).