Introduction to Limit State Design - Design and drawing of Steel Structure

TL;DR

The limit state method of design focuses on the ultimate conditions beyond which a structure can no longer fulfill design criteria, ensuring both strength and serviceability requirements are met.

Transcript

hello everyone in this video we are going to see introduction to the limit state method of design in previous video we have seen working stress method now we will see the limit state method of design so what limit state or what in short it is also known as lsm or lsd limited method of design or limited method just so what exactly is this method see... Read More

Key Insights

• 🎨 The limit state method of design considers the ultimate conditions a structure can withstand, ensuring it meets both strength and serviceability requirements.
• ⛔ Limit state of collapse focuses on factors like bending moment, shear force, torsion, and axial forces, while the limit state of serviceability looks at deflection, cracking, and vibration.
• 💀 The method analyzes the structure under various loads, including dead load, live load, wind load, and earthquake load.
• 😒 It uses load combinations to determine the critical design load for a structure and ensures stability, appearance, durability, and fire resistance.
• 💦 The limit state method of design offers a safer and more comprehensive approach compared to the working stress method.
• 🧑‍🏭 Factors like deformation, vibrations, corrosion, and repairable damages are considered under the limit state of serviceability.
• 👨‍💻 The limit state method of design follows code 1893 and its combinations provided in part one and part two.

Questions & Answers

Q: What is the limit state method of design?

The limit state method of design is an approach that considers the ultimate conditions beyond which a structure cannot fulfill design criteria. It focuses on both the strength and serviceability requirements of a structure.

Q: How does the limit state method of design differ from the working stress method?

The limit state method considers various limit states, such as collapse and serviceability, and checks the structure against each of them. In contrast, the working stress method applies a factor of safety to a single design load.

Q: What are the two types of limit states in the limit state method of design?

The two types of limit states are the limit state of collapse (strength) and the limit state of serviceability. The limit state of collapse deals with factors like bending moment, shear force, torsion, and axial forces, while the limit state of serviceability considers deflection, cracking, and vibration.

Q: How does the limit state method ensure structural safety?

The limit state method of design analyzes the structure for all possible combinations of design loads and checks each part and the whole structure against these loads. It ensures that the structure remains stable, does not experience excessive deformation, and can withstand expected environmental conditions and fire.

Summary & Key Takeaways

• The limit state method of design considers the maximum capacity of a structure to resist loads beyond which it no longer meets design criteria.

• It involves two types of limit states: limit state of collapse (strength) and limit state of serviceability.

• The limit state of collapse deals with factors like bending moment, shear force, torsion, and axial forces, while the limit state of serviceability considers deflection, cracking, and vibration.