Applies To
	Product(s):	STAAD Advanced Concrete Design
	Version(s):	Connect Edition
	Environment:
	Area:	Concrete Design
	Subarea:	General
	Original Author:	Ranjana, Bentley Technical Support Group

    Explain how the Live load reduction as per Table-10 of IS 1893-2016 is handled in RCDC. And how live load reduction available in RCDC works for this?

• IS 1893-2016 – Table-10 is for percentage of Imposed Load to be considered in calculation of seismic weight. Refer below snap,

   

  The lump mass for the earthquake load is calculated based on the % of vertical load. It is assumed in the code that during earthquake live load intensity would not be full. Thus, for the calculation of seismic weight, we can reduce the live load. The dead load is considered 100%. The live load is considered as per table above. It is related to lateral loads.

  Please note that this reduction is only to calculate seismic weight which we considered for lateral load calculation for earthquake load conditions. It is not related to vertical live load on column and beam.

  It must handle in analysis part as it will govern the load to be applied laterally for earthquake.

   Please note that, it is not applicable for Wind loads, as these loads are not depending on the Building weight.

   The live load reduction given in Is 875, is for the vertical load. The reduction is applied floor wise as per the number of stories supported by column and footing. Please note that, it is not applied for beam and slab design.

   The intention of the code here is at a time, building would not be occupied by full live load for exposed area. Thus, we can take advantage of partially occupied area. Thus, the Live load reduction is as per no of stories supported by column and foundation and it is maximum 50%.

  For calculation of seismic weight 'full live load' need not be considered. For design of elements, the effect of this EQ (in member) is considered with appropriate load factor of the combination. With regards to the combination of DL+LL+EQ, one can consider the reduced LL as explained. (based on the number of levels supported).