# Daffodil International University

## DIU Activities => Permanent Campus of DIU => Topic started by: Shihab Ahammed on July 11, 2018, 11:36:56 PM

Title: Difference between pushover and seismic analysis
Post by: Shihab Ahammed on July 11, 2018, 11:36:56 PM
Seismic analysis generally is a dynamic analysis which may be linear or nonlinear while pushover is a nonlinear static analysis. The difference is in Pushover you try to get the capacity of the building for maximum displacement and in seismic analysis you try to keep your displacements under control as per codes.

Pushover is generally performed for retrofitting purposes where the building is old and you are doing some rehabilitating work. And many times in case of 10-12 story regular building. But as pushover is a static analysis and it does not capture the torsional effects accurately it is avoided for irregular buildings. Today all the computers can quickly perform linear dynamic analysis and it takes about 30-40 seconds to run it. So why not capture the dynamic effects for new buildings? That is why pushover analysis is slowly drifting away from design of new buildings.
Title: Re: Difference between pushover and seismic analysis
Post by: hussainuzaman on July 15, 2018, 10:16:33 AM
Thank you for the nice posting.
Is there any figures to explain these two types of analysis? Which softwares can perform these analysis?
Title: Re: Difference between pushover and seismic analysis
Post by: Shihab Ahammed on August 01, 2018, 09:45:01 PM
sir,
I used SAP to perform time history analysis..ETABS and SAP can be used to perform both the analysis. Sir, there are some videos regarding these anaylis
Title: Re: Difference between pushover and seismic analysis
Post by: Ananda Ghosh on September 22, 2018, 12:43:02 PM
As per i know from my undergrad thesis, the main basic difference between the pushover analysis and Time history analysis is that, in pushover analysis, the earthquake magnitude(accelerogram) is generated by the ETABS software. We have no control on it to create this artificial lateral load. We can not modify any factor for observing variable phenomena. On the other hand in time history analysis, a real life earthquake is chosen. It can be applied in any point with some factorization for real time observation. That's it.

In case of  pushover,  SAP can be  the best option and but ETABS (latest version) is chosen for time history analysis. Because our latest BNBC code can be followed in the latest version making factor(c,k) changed.
Title: Re: Difference between pushover and seismic analysis
Post by: Shihab Ahammed on September 25, 2018, 10:13:49 PM
thanks for enlightening us Ananda Ghosh