How is Working Stress Method (ASD) different from Limit state method (LRFD or LFD)? Assumptions, Advantages and comparisons

working stress method

How is Working Stress Method (ASD) different from Limit state method (LRFD or LFD)? Assumptions, Advantages and Comparisons Limit state method (LRFD or LFD) “A limit state is a condition beyond which a structural system or a structural component ceases to fulfill the function for which it is designed” Various limit states are Strength limit … Read more

What is Resilience and Modulus of Resilience?

Resilience and Modulus of Resilience

Resilience and Modulus of Resilience Resilience. Resilience is the total elastic strain energy which can be stored in the given volume of metal and can be released after unloading. it is also equal to area under load deflection curve within elastic limit. Modulus of Resilience is defined as elastic strain energy per unit volume and … Read more

Toughness and Impact Strength of Metals

Charpy test

Toughness and Impact Strength of Metals Toughness is the resistance to the impact loading against fracture. If a metals is tough, then it has the ability to store large strain energy before failure, deflection curve up to fracture stage. Modulus of Toughness It is the total strain energy per unit volume upto fracture stage. it … Read more

What is Proof Stress?

Proof Stress and Proof Resilience

Proof Stress In some ductile materials such as Aluminium, Copper, Mild Steel, the yield point cannot be clearly defined during tension test, therefore yield stress is Unknown. For such metals design stress called PROOF stress is calculated using offset method. An offset of strain equal to given permissible plastic strain, eg at 0.2% for Al, … Read more

6 Reasons why Mild Steel is most commonly used metal in Civil Engineering for Reinforced Concrete

High Tensile Deformed Bar

Why Mild Steel is most commonly used metal in Civil Engineering for Reinforced Concrete? Even though there are lots of metals (like Aluminium, Cast iron ) available for reinforcing concrete, Mild Steel is the most widely used reinforcing material in reinforced concrete. Following are the major reasons behind this. It is highly ductile. The Young’s … Read more

Failure modes in beams | Types of Failure in Reinforced Concrete Beams

Development Of Cracks in Beams

Failure Modes in beams There are two common types of failure in slender, non Prestressed flexural elements that carry the load in one direction only are Compression failure of the Compressive Chord “ductile flexural failure”:  After yielding of the reinforcement, if no redistribution of forces is possible, the deformations of the beam become important while … Read more

Ductile Fracture of Metals by Necking – Cup and Cone Failure

Cup and cone of mild steel road after Necking

Ductile Fracture of Metals by Necking – Cup and Cone Failure extensive plastic deformation and energy absorption (“toughness”) before fracture Fracture: separation of a body into pieces due to stress, at temperatures below the melting point. Steps in fracture: crack formation crack propagation Major Fracture Mechanisms Depending on the ability of material to undergo plastic … Read more

Buckling of Columns – Euler Theory for Elastic Buckling

Buckling of Concrete Columns

Buckling of Columns – Euler Theory for Elastic Buckling BUCKLING – Loss of stability –Axial loads cause lateral deformations (bending-like deformations) Buckling of Columns is a form of deformation as a result of axial- compression forces. This leads to bending of the column, due to the instability of the column. This mode of failure is … Read more

Fracture in Steel – Brittle fracture in ductile material

Brittle Cracking of a Wide Flange Beam

Fracture in Steel – Brittle fracture in ductile material Brittle failure is the brisk propagation of cracks through a material. This typically occurs so quickly that no plastic deformation takes place before fracture occurs. In structure failures, brittle failure usually causes a failure in structural integrity. Because of the rapid nature of this failure, it often leads … Read more