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CMAA 70 any formula for the calculation of bumper load /impact load , Cbs? i have not found any

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F4ng

Structural
Apr 14, 2016
2
Lutfi (Structural)4 Sep 03 21:44
Better yet get the CMAA 70 and 74 code books. They have very detailed method and formulas on how to compute the crane stops. Dr. Blodgett’s approach is identical to theirs.

Also AISC published industrial building design guide/recommendations that tackle the cranes and crane stops.

Good luck.
-----------------the above is what i found here, now,-------------------------------
hi there, I looked into the CMAA 70, not found any...detailed,
anyone has any simple direct way to calculate? I would assume , to be safe, worst case, the bumper does not work/function in case of a 3 ton crane hit on stop, 5-10% kenitic energe gone to those hardware whatever, then 95- 90% kenitic energe, (m v0 ^2 /2) , v0= 100 ft/minute for a 3 ton crane, then to a stop (vt=0), in, let us say, 1 second time, 90% kenitic energe transfered to hit-load/impact /bumper load to my one side runway column , due to worst case of non-symetric stop on 2 runways, then I will get a Force, i use that Force;
i have a load factor of 1.0 on my C7 (as per CISC guide ) ( here in Canada) , then i might consider a more general condition of symetrical, 50% energe transfered to structure in 1-1.5 second of time;
so , simple, i will have my vt=0 , v0 equivalant, t, then F= (M (v0-0))/t ..., got the V0e from the 90% or 95% of the initial E,
Since the change of momentum equals to the exerted impulse
mv2-mv1=Ft

F=( mv2-mv1)/t, where v2 =0, v1 from E disipation +E2 = E1 = E(v0=100 ft/minute).
your comments please,

 
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