Causes and Prevention of Structural Failures
The design of structures should satisfy three fundamental requirements:
1. Stability: The structure should be stable under the action of loads.
2. Strength: The structure should resist safely stresses induced by the loads.
3. Serviceability: The structure should perform satisfactorily under service loads.
Stability, strength and serviceability can only be achieved by following basic design principles. This paper presents different structural failures, so other engineers can benefit from this knowledge.
Part of a building in Vijayawada collapsed one early morning killing a person. On inspection, it was found that the collapsed part was constructed adjacent to the main building with 25mm expansion joint. The collapsed building was constructed on two columns. Each column has 6-16mm main steel. Load from each column is transferred to a single under reamed pile. Which has 6-10mm bars.
It appears that the collapse is due to three causes:
1. The over lap length of steel rods at the junction of pile & column is inadequate.
2. Structure is unstable due to number of columns used (two only)
3. Unsymmetrical wall load on the structure.
The collapse of the building could have been prevented by structurally connecting it to main building there by providing stability.
Collapse of a Foot–Bridge
A Footbridge in Vijayawada collapsed one day before opening & fell into the canal below killing two painters. The footbridge has a span of 40m. It consisted of two welded trusses, cross girders & precast RCC slabs. On inspection, it was found that the welding is defective.
Following the provisions in IS code for structural steel fabrication would have prevented this failure.
Collapse of a Residential Building
One evening in Vijayawada, a three story residential building (Fig 2.) collapsed a day before occupancy killing watchman & his family.
On inspection, it was found that...