Civil Engineering/Modellling in etabs
QUESTION: hi sir,
i am performing seismic assessment of a G+3 stored building under seismic zone 2 in india using etabs, i had few doubts regarding modelling of building in etabs:
1. how do i input bent up bars and stirrups in beams and columns using this software.
2. whether i should include plinth level beams for the purpose of assessment and if i will include how does it effect the whole structure and if i don' how does it effect.
as i had studied regarding plinth level beams someone has said that we should include plinth beams if the effect of these beams are major in contribution to the lateral stiffness of the whole frame/structure.
if so, how should i calculate the effect of plinth level beams on lateral stiffness of whole frame.
looking forward for your prompt response.
ANSWER: Dear Hemanth
1- Etabs is a structural analysis softwares which is based on macro modelling of the structure. You dont need to apply such a details to analyse your structure.
2- Plinth beams are secondary systems which cant be analyzed directly. they simply and implicitly the reliability of foundations against slipping under lateral loads. A plinth beam mobilize the neighbour footing to contribute to bear lateral loads applied be a specific frame which may be braced and bearing lateral forces.
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QUESTION: thank you for your response sir,
the 2nd answer was not so clear to me as i am a 2nd year under graduate student
so, please can you elaborate and reply to me sir whether to include plinth beams are not.
sorry for the trouble caused by me to you.
Actually you dont need to model explicitly the plinth beams neither the reinforcement details and so on. You should design a plinth beam according to results of structural analysis. Then you dont have to model them in your structural analysis file.'