Q3(a). Describe the reasons for earthquake and suggest measures for the construction of earthquake-safe buildings.

“Earthquakes don’t kill people; unsafe buildings do.” - UNDRR Report

Earthquakes occur due to the sudden release of energy in the Earth’s crust, mainly caused by tectonic plate movements. India lies at the convergence of the Indian and Eurasian plates, making it highly vulnerable, with 59% of the landmass prone to moderate or severe earthquakes (NDMA).

Major Reasons for Earthquakes in India

Tectonic Activity:

Collision of Indian Plate with Eurasian Plate leads to strain accumulation, frequent in the Himalayas (Zone V).

Fault Line Movements:

Indo-Gangetic plains and Aravalli–Delhi ridge are seismically active.

Volcanic and Reservoir-Triggered Earthquakes:

Reservoir-induced seismicity in western India (Koyna Dam, Maharashtra).

Human-Induced Causes:

Deep mining, groundwater over-extraction, hydrocarbon exploration.

Measures for Earthquake-Safe Building Construction

1. Adherence to BIS Codes: IS 1893 (Seismic Design) and IS 4326 for masonry buildings.
2. Use of Ductile Reinforcement: Ensures flexibility and prevents brittle collapse.
3. Base Isolation & Shock Absorbers: Separates building from ground motion.
4. Lightweight Materials: Reduces inertia forces during shaking.
5. Retrofitting Old Structures: Adding steel braces, shear walls and jacketing columns.
6. Local Building Bylaws: Haryana’s Urban Local Bodies follow earthquake-resistant norms in Gurugram, Faridabad high-rise zones.

A combination of scientific planning, strict enforcement, and public awareness is essential to minimize earthquake-related losses.