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Time-History Verification

Time-History Verification

Time-History Verification

(OP)
I'm modeling a 6 story building that I hope to verify against actual test data.  

All preliminary tests are conclusive but I am unable to include dead load within my time-history analysis.  My base reaction (Z) for static dead load case is 810kips.  My base reaction (Z) for my time-history acceleration load case is 0.165 kips.  

I'm running a time-history function of base accelerations using non-linear, direct integration and p-delta.  My time integration method is Hibler-Hughes- Taylor with an Alpha factor of -0.33.  Mass and stiffness proportional damping is 0.5%.  I've run nearly all related parameters and still cannot get my time-history acceleration load case to show any significant change in Base Reaction (Z).  

I've done runs with:
Load Pattern self-weight multiplier is set for 1.0 or 0 on the two load cases (Dead and ACC)
Frame gravity multiplier set to 1.0 or 0 on both Load Patterns

I've done all combinations of these runs to no avail as well as defining mass source to the load patterns.

I have also given my Dead load case a non linear direct integration function and applied it with my Acceleration Case. Once again, I cannot activate the dead load in my acceleration cases.  

Could I be reading the output Base Reactions table wrong?  Dead Load, according to the table, is spot on (within a few hundred pounds of the actual test building).  

Any advise/insight would be greatly appreciated!

Thanks

Tyler




 

RE: Time-History Verification

Hello tfosterwsu
Your problem is incomprehensible
If you joint your sap file maybe will help engineers to detect what's wrong with it.

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