Zouatine
Structural
- Mar 18, 2020
- 36
Respected All,
Hope you are doing well,
Kindly, I'm trying to design a shear wall in sap2000 to resist the earthquake load. As you may known that sap2000 doesn't have the option to design the shear wall so for this reason I'm using a wider column approach, where instead of modelling the shear wall as a shell element we use a column with same cross section as the shear wall (picture is attached).
The same model was created using the Etabs software for the sake of comparison between the wider column and the shear wall modelling option in Etabs ,the comparison was based on the design (reinforcement).
the designed RC structure has eight stories . From the 1st to the 3rd story , the rebar area from the wider column approach and the Etabs model is approximately the same the difference is roughly 5%. the only concerning thing is the upper stories starting from the 4 story, the sap2000 for the wider column approach gives a constant rebar area 174000mm2 , even though , I checked the design axial and moment forces they are not the same ( decreasing when from story to another story ) but still sap2000 is giving the same reinforcement. Where in the Etabs the reinforcement is less when we go from a story to another one which i believe is the correct one.
the wider column modelling in sap2000.
Reinforcement from the sap2000 (wider column app)
Reinforcement from etabs ( where the shear wall is modeled as a shell element .
the design forces in the 8th floor from the sap2000 ( wider column app).
the design forces in the 4th floor from the sap2000 ( wider column app).
the design are not the same but the reinforcement is the same ????
Would you please help me with any thoughts why the sap2000 is given a constant reinforcement area starting from the 4th story ?
Thank you waiting for your kind replies.
Hope you are doing well,
Kindly, I'm trying to design a shear wall in sap2000 to resist the earthquake load. As you may known that sap2000 doesn't have the option to design the shear wall so for this reason I'm using a wider column approach, where instead of modelling the shear wall as a shell element we use a column with same cross section as the shear wall (picture is attached).
The same model was created using the Etabs software for the sake of comparison between the wider column and the shear wall modelling option in Etabs ,the comparison was based on the design (reinforcement).
the designed RC structure has eight stories . From the 1st to the 3rd story , the rebar area from the wider column approach and the Etabs model is approximately the same the difference is roughly 5%. the only concerning thing is the upper stories starting from the 4 story, the sap2000 for the wider column approach gives a constant rebar area 174000mm2 , even though , I checked the design axial and moment forces they are not the same ( decreasing when from story to another story ) but still sap2000 is giving the same reinforcement. Where in the Etabs the reinforcement is less when we go from a story to another one which i believe is the correct one.
the wider column modelling in sap2000.
Reinforcement from the sap2000 (wider column app)
Reinforcement from etabs ( where the shear wall is modeled as a shell element .
the design forces in the 8th floor from the sap2000 ( wider column app).
the design forces in the 4th floor from the sap2000 ( wider column app).
the design are not the same but the reinforcement is the same ????
Would you please help me with any thoughts why the sap2000 is given a constant reinforcement area starting from the 4th story ?
Thank you waiting for your kind replies.