\begin{equation} \begin{array}{|c|l|l|} \hline \text { S. No. } & \text { Working stress method (WSM) } & \text { Limit state method (LSM) } \\ \hline 1 & \text { Stress-strain behavior is linear } & \text { Stress-strain behavior is non linear } \\ \hline 2 & \text { WSM is also known as plastic design } & \text { LSM is also known as elastic design } \\ \hline 3 & \begin{array}{l} \text { WSM is stress based method of RCC } \\ \text { design } \end{array} & \begin{array}{l} \text { LSM is strain based method of RCC } \\ \text { design } \end{array} \\ \hline 4 & \begin{array}{l} \text { In WSM, the material follows Hookes' } \\ \text { law as stress is not allowed to cross the } \\ \text { yield limit. } \end{array} & \begin{array}{l} \text { In LSM, stress is allowed to cross } \\ \text { the yield limit } \end{array} \\ \hline 5 & \begin{array}{l} \text { A section which is plane before bending } \\ \text { remains plane even after bending } \end{array} & \begin{array}{l} \text { A section which is plane normal to } \\ \text { the axis of structural component } \\ \text { remains plane after bending. } \end{array} \\ \hline 6 & \begin{array}{l} \text { In WSM, safety factor is considered. } \\ \text { In LSM, partial safety factor is } \\ \text { considered. } \end{array} \\ \hline 7 & \begin{array}{l} \text { In WSM, tensile stresses of concrete are } \\ \text { considered. } \end{array} & \begin{array}{l} \text { In LSM, tensile stresses of concrete } \\ \text { are not considered. } \end{array} \\ \hline 8 & \begin{array}{l} \text { Modular ratio } \\ \text { taken into consideration to calculate } \\ \text { allowable stresses. } \end{array} & \begin{array}{l} \text { The ultimate stresses are considered } \\ \text { as allowable permissible stresses. } \end{array} \\ \hline \end{array} \end{equation}Show More

\begin{equation} \begin{array}{|c|l|l|} \hline \text { S. No. } & \text { Working stress method (WSM) } & \text { Limit state method (LSM) } \\ \hline 1 & \text { Stress-strain behavior is linear } & \text { Stress-strain behavior is non linear } \\ \hline 2 & \text { WSM is also known as plastic design } & \text { LSM is also known as elastic design } \\ \hline 3 & \begin{array}{l} \text { WSM is stress based method of RCC } \\ \text { design } \end{array} & \begin{array}{l} \text { LSM is strain based method of RCC } \\ \text { design } \end{array} \\ \hline 4 & \begin{array}{l} \text { In WSM, the material follows Hookes' } \\ \text { law as stress is not allowed to cross the } \\ \text { yield limit. } \end{array} & \begin{array}{l} \text { In LSM, stress is allowed to cross } \\ \text { the yield limit } \end{array} \\ \hline 5 & \begin{array}{l} \text { A section which is plane before bending } \\ \text { remains plane even after bending } \end{array} & \begin{array}{l} \text { A section which is plane normal to } \\ \text { the axis of structural component } \\ \text { remains plane after bending. } \end{array} \\ \hline 6 & \begin{array}{l} \text { In WSM, safety factor is considered. } \\ \text { In LSM, partial safety factor is } \\ \text { considered. } \end{array} \\ \hline 7 & \begin{array}{l} \text { In WSM, tensile stresses of concrete are } \\ \text { considered. } \end{array} & \begin{array}{l} \text { In LSM, tensile stresses of concrete } \\ \text { are not considered. } \end{array} \\ \hline 8 & \begin{array}{l} \text { Modular ratio } \\ \text { taken into consideration to calculate } \\ \text { allowable stresses. } \end{array} & \begin{array}{l} \text { The ultimate stresses are considered } \\ \text { as allowable permissible stresses. } \end{array} \\ \hline \end{array} \end{equation}

The salient features of the working stress method are as follows;

1. It uses elastic theory for the design of structures, which considers the stress distribution as linear up to the collapse of the structure.
2. It accounts working loads during the design.
3. It uses factor of safety (FOS) for concrete in bending as 3, FOS for concrete in compression as 4 and FOS for steel as 1.78.

The salient features of limit state method are as follows;

1.  It uses multiple safety factor formats for the design of structures, which attempts to provide adequate safety at ultimate loads as well as adequate serviceability at service loads. 
2. It accounts the design loads during the design.
3. It uses two limit states; a) Ultimate limit state b) Serviceability limit state.

Difference between Working Stress and limit stress  Philosophy:

S.NO.	Working Stress Method (WSM)	Limit State Method (LSM)
1	Stress-strain behavior is linear.	Stress-strain behavior is non linear.
2	WSM is also known as plastic design.	LSM is also known as elastic design.
3	WSM is stress based method of RCC design.	LSM is strain based method of RCC design.
4	In WSM, the material follows Hookes law as stress is not allowed to cross the yield limit.	In LSM, stress is allowed to cross the yield limit.
5	A section which is plane before bending remains plane even after bending.	A section which is plane normal to the axis of structural component remains plane after bending.
6	In WSM, Safety factor is considered.	In LSM, partial safety factor is considered.
7	In WSM, tensile stresses of concrete are considered.	In LSM, tensile stresses of concrete are not considered.
8	Modular ratio, `m=280/(3 sigma_(c b c))` is generally taken into consideration to calculate the allowable stresses.	The ultimate stresses are considered as allowable permissible stresses.

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The salient features of the working stress method are as follows;

1. It uses elastic theory for the design of structures, which considers the stress distribution as linear up to the collapse of the structure.
2. It accounts working loads during the design.
3. It uses factor of safety (FOS) for concrete in bending as 3, FOS for concrete in compression as 4 and FOS for steel as 1.78.

The salient features of limit state method are as follows;

1.  It uses multiple safety factor formats for the design of structures, which attempts to provide adequate safety at ultimate loads as well as adequate serviceability at service loads. 
2. It accounts the design loads during the design.
3. It uses two limit states; a) Ultimate limit state b) Serviceability limit state.

Difference between Working Stress and limit stress  Philosophy:

S.NO.	Working Stress Method (WSM)	Limit State Method (LSM)
1	Stress-strain behavior is linear.	Stress-strain behavior is non linear.
2	WSM is also known as plastic design.	LSM is also known as elastic design.
3	WSM is stress based method of RCC design.	LSM is strain based method of RCC design.
4	In WSM, the material follows Hookes law as stress is not allowed to cross the yield limit.	In LSM, stress is allowed to cross the yield limit.
5	A section which is plane before bending remains plane even after bending.	A section which is plane normal to the axis of structural component remains plane after bending.
6	In WSM, Safety factor is considered.	In LSM, partial safety factor is considered.
7	In WSM, tensile stresses of concrete are considered.	In LSM, tensile stresses of concrete are not considered.
8	Modular ratio, `m=280/(3 sigma_(c b c))` is generally taken into consideration to calculate the allowable stresses.	The ultimate stresses are considered as allowable permissible stresses.