In working stress method we are designing the structure for
the load acting on the structure.
In limit state method we are designing for the limit state of
safety and serviceability by applying partial safety factor
partly for the load or moment and partly for the stress
induced in the structure.
in limit state load is overesimate than actual,so we can
assure more reliable.safe than wsm. hence we can obtain
suitable section which is stronger than wsm. it is verry
common. wsm only suitable for chimney, water tank ....etc
In case of design procedure , the facted load can be taken
for limit state mtd, by working stress method axial load
can be taken and strength of material is low, by limit
state method strength of material is high.