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Saddle calculation as per LP Zick Method (div 1)

Saddle calculation as per LP Zick Method (div 1)

Saddle calculation as per LP Zick Method (div 1)

While going through compress calculation, I found some doubts while taking the loads during calculation.

1)    Bending Moment calculation at the saddle
Mq = w*(2*H*Al / 3 + Al^2 / 2 - (R^2 - H^2) / 4)
Where, w=Wt/(L+4H/3)
As per compresses calculation, Wt is taking as total operating weight. As my concern is that it is missing the additional load due to either wind/seismic during moment calculation that means it is neglecting the stress due to wind/seismic at the saddle support. Am I correct?

2)    Shear stress Calculation:
Same problem I found  calculating shear stress.
Qshear = Q - w*(a + 2*H / 3)
Where, Q=total weight +seismic/wind load
W=unit operating weight per effective length.
Am I right guy?

RE: Saddle calculation as per LP Zick Method (div 1)

The calculation of 'w' and 'Q' include the seismic or wind loadings.

Compare the numbers in the calculation rather than just looking at the equations.

Notice that Q involves Ql and Qt; both of those use the wind shear V and the largest of the two is added to W.

w is harder to show but it works out.

RE: Saddle calculation as per LP Zick Method (div 1)

if u see my attached file with additional wind load calculation u will see that

Q = Weight on saddle + larger of Qt or Ql
Q = W + Qt = 79,124.98 + 5,697.82 = 84,822.79 N

w = Wt / Le = 157,271.34*10 / 6,648 = 236.57 N/cm

where total operating weight= wt on saddles  

During calculation of Bending Moment calculation at the saddle
Mq = w*(2*H*Al / 3 + Al^2 / 2 - (R^2 - H^2) / 4)

don't u think it miss the additional load Qt (5697.82N) while calculating Mq? It's clear.

u can check in ur compress model also with additional loads(seismic or wind).

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