×
INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

Are you an
Engineering professional?
Join Eng-Tips Forums!
• Talk With Other Members
• Be Notified Of Responses
• Keyword Search
Favorite Forums
• Automated Signatures
• Best Of All, It's Free!

*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

#### Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

# Seismic: Zero Period Acceleration & Zone Factor

## Seismic: Zero Period Acceleration & Zone Factor

(OP)
1. Zero Period Acceleration
2. Zone factor
Their relation to each other if any (formula).

Regards,
s1111

### RE: Seismic: Zero Period Acceleration & Zone Factor

I'll give it my best shot:
If a flexible structure is subject to an earthquake, the movement of the structure will vary depending on the frequencies of the earthquake versus the natural frequencies of the structure.  If the structure is perfectly rigid, its natural frequency is infinite, its period is zero, and it simply moves in unison with the ground, and the acceleration should be the "Zero Period Acceleration" in that case.  That may be adjusted by various other factors as well, and you would need to check the exact definition in the source you're using.  A structure with zero period would be a "rigid structure" in ASCE 7-05, if I remember the terminology right.

In older seismic codes, they had the US divided into 4 or 5 different seismic zones, and depending on which zone, you used a specific coefficient in the seismic design.  Generally, the acceleration used in the design would be proportional to these zone factors.  Current seismic codes use maps with continuous variation in the different variables, rather than distinct zones.  See ASCE 7-05, for example.  In referring to ASCE 7, see the section on "non-building structures not similar to buildings".

Hope this helps, if not, perhaps explain more specifically what you're trying to do.

### RE: Seismic: Zero Period Acceleration & Zone Factor

(OP)
Thank you JStephen for your feedback.

regards,
s1111

#### Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

#### Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

#### Resources

eBook - 10 Reasons to Choose CATIA on the Cloud
To compete in todayâ€™s fast-paced and competitive market, smaller and newer firms need a powerful platform that will enable them to compete with bigger players, without the heavy investments needed in computer hardware, software and personnel. Download Now
White Paper - Smart Manufacturing for Electronics
This white paper describes a transformative approach to electronics manufacturing made possible by the addition of Mentor Graphics to the Siemens family. It describes a completely digitalized strategy that supports both printed circuit board (PCB) and mechanical design and manufacturing, uniting the entire product lifecycle â€“ from idea and production to customers and back. Download Now

Close Box

# Join Eng-Tips® Today!

Join your peers on the Internet's largest technical engineering professional community.
It's easy to join and it's free.

Here's Why Members Love Eng-Tips Forums:

• Talk To Other Members
• Notification Of Responses To Questions
• Favorite Forums One Click Access
• Keyword Search Of All Posts, And More...

Register now while it's still free!