Dear Richard/Dave.

For Two phase flow analysis, we are using C-II dynamic response spectrum method.

I learnt from the basis, DLF max will be 2. (Two - No of cycles used)

But in my case surprisingly, it touches 4.

Please check once, Correct me If I am wrong

Please find the report(DLF vs freq) generated by C-II after entering our input time vs force.

* USER ENTERED TIME HISTORY PULSE
* TIME(milliseconds) FORCE(N. )
* 0.00000 1155.79
* 22.08048 1155.79
* 23.00000 0.00
* 179.51613 0.00
* 180.00000 1155.79
* 201.59662 1155.79
* 202.00000 0.00
* 359.03226 0.00


* FREQ (HZ) MULTIPLIER
0.0002063 0.0907975
0.0033000 0.0037244
0.0167063 0.0067488
0.0528000 0.0151095
0.1289062 0.0360342
0.2673000 0.0739524
0.4952062 0.1333364
0.8448001 0.2101690
1.3532062 0.2735129
2.0625000 0.2910598
3.0197065 0.4244100
4.2768006 0.8796148
5.8907051 1.5775653
7.9232974 1.0641319
10.4413996 2.4652064
13.5167885 1.6349050
17.2261925 3.5805736
21.6512794 3.7416873
26.8786774 3.2443714
32.9999619 3.0339775

A DLF of 2 is the maximum ratio of (induced load/applied load) for a single impulse load. You have two impulses in your time history.

YES, I checked for single cycle DLF max 2 is coming

Thank you for your clarification.