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Calculating Seismic NonBuilding Component-ASCE 7-02, 9.14

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BPres

Mechanical
Feb 1, 2005
24
I'm a mechnical engineer and have designed a base frame to support 8 motor driven components. Per customer I have to design to meet ASCE 7-02, 9.14.

I find that in Section 2.0, Combinatins of Loads,equations 2.3.2.5 and 2.3.2.7 are the ones applicable to this case.

So, the questions are;

1) How do I used the E values. Equasions 9.5.2.7- and -2 imply I should use both values to see which has most affect, right?

2) I'm using an FEA software to do the analysis. To use the forces, I have to convert them to accelerations. How do you split the Combinations of Loads for horizontal and vertical?
Should I go all the way back to equ. 9.5.2.7- and -2?

I'm confused about how to apply forces and accelerations.
 
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I've done some of this non-building structure stuff only from the civil-structural side though.

Are you designing the mechanical components to meet a wind/seismic event? Or is this intended for anchorage?

I only have the 7-05 on me but I'd guess seismic coeff for mechanical/electrical components are addressed in 13.6. Is that the same chapter as 9 in the 7-02?
 
I'm designing to meet seismic requirements. Yes, Chap. 9 of 7-02 is the same as Chap. 13 of 7-05.

Looking at 7-05 Chap. 12.4, I believe I understand for non-buildings, paragraph 12.4.2.3, Strength Design, I would use #5 for upward seismic acceleration and #7 for downward seismic acceleraton. Is that correct? Many times our customer gives us different Sds values for vertical and horizontal. In which case Sds(vert) is applied to the 0.2Sds part and Sds(horz) is applied to Qe (Qe=Fp of non-building)of both #5 and #7 , correct?

Comparing 7-05 with 7-02 I'd say the same cases apply to 2.3.2 of 7-02. It is just not explained as clearly as in 7-05.

 
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