Reinforced Concrete Buildings In recent times, reinforced concrete buildings have become common in India, particularly in towns and cities. Reinforced concrete (or simply RC) consists of two primary materials, namely concrete with reinforcing steel bars. Concrete is made of sand, crushed stone (called aggregates) and cement, all mixed with pre-determined amount of water. Concrete can(…)
Effects on Structures
HOW BUILDINGS TWIST DURING EARTHQUAKES?
Why a Building Twists In your childhood, you must have sat on a rope swing – a wooden cradle tied with coir ropes to the sturdy branch of an old tree. The more modern versions of these swings can be seen today in the children’s parks in urban areas; they have a plastic cradle tied(…)
SEISMIC DESIGN PHILOSOPHY FOR BUILDINGS
The Earthquake Problem Severity of ground shaking at a given location during an earthquake can be minor, moderate and strong. Relatively speaking, minor shaking occurs frequently, moderate shaking occasionally and strong shaking rarely. For instance, on average annually about 800 earthquakes of magnitude 5.0-5.9 occur in the world while the number is only about 18(…)
ARCHITECTURAL FEATURES & EARTHQUAKE
Importance of Architectural Features The behaviour of a building during earthquakes depends critically on its overall shape, size and geometry, in addition to how the earthquake forces are carried to the ground. Hence, at the planning stage itself, architects and structural engineers must work together to ensure that the unfavourable features are avoided and a(…)
SEISMIC EFFECTS ON STRUCTURES
What are the Seismic Effects on Structures? Inertia Forces in Structures Earthquake causes shaking of the ground. So a building resting on it will experience motion at its base. From Newton’s First Law of Motion, even though the base of the building moves with the ground, the roof has a tendency to stay in its(…)