Structural failures in buildings can lead to serious consequences, making it crucial to understand their causes and take preventive measures. This article delves into the various factors contributing to structural failures and emphasizes the importance of vigilant construction practices.
1. Design Flaws :
Engineers strive for perfection in design, but certain criteria require attention. Over-reinforcing concrete may lead to sudden, brittle failures, while under-reinforcement allows for ductile failure, giving engineers time to take precautions. Nondestructive testing methods such as Rebound Hammer Test and Ultrasonic Pulse Velocity aid in identifying potential issues.
2. Improper Curing :
Cement hydration issues arise in hot and cold weather concreting, necessitating measures like using rapid-hardening cement in hot weather and steam curing in cold weather. Techniques like wet gunny bags, polyethenes, or ponding immersion trap moisture during hot weather concreting.
3. Inadequate Compaction :
Insufficient compaction results in voids in concrete, hindering the binding of cement to aggregates. Vibration machines provide consistent compaction, unlike manual compaction prone to fatigue.
4. Steel Failures :
Corrosion of steel due to moisture contact is common. Proper compaction protects steel, and using high-grade steel like Fe 500 or Fe 550, along with a higher number of small diameter bars, prevents structural failures.
5. Soil Conditions :
Liquefaction can cause tilting or immersion of buildings, emphasizing the need for thorough soil testing before construction. Preventive measures are crucial, as rectifying soil-related issues post-construction can be expensive.
6. Natural Calamities :
Structural failures due to earthquakes, hurricanes, tsunamis, and volcanic eruptions are unavoidable. Following seismic design codes like IS 13920:2016 and IS 1893:2016 ensures safe construction practices against natural disasters.
1. Kemper Arena in Kansas City
The arena’s roof collapsed during heavy rain due to design flaws, violating local codes and resulting in a violent collapse.
2. Lotus Riverside Complex, China
A newly built apartment building collapsed due to soil instability caused by depositing excavated soil on a nearby river bank.
3. Hyatt Regency Walkway Collapse, Kansas City
Last-minute design changes led to the collapse of walkways, causing one of the deadliest structural failures in US history.
Structural failures demand attention and preventive action. Proper planning, adherence to design principles, and avoidance of last-minute changes are essential to ensure building safety. Civil engineers must prioritize safe design practices to prevent structural failures, recognizing that prevention is more effective than remedies.
