reduce sway in free standing stair system
reduce sway in free standing stair system
(OP)
I have a few free standing stairs and platforms that seem to be swaying a little too much for the people using them. These stairs and platforms have been analyzed for loads specified in ASCE-7 and deflections limited to 1/4 inch. I recommended and designed cross bracing to limit the sway. I don't have the ability to predict vibrations and movement caused by people using the stairs. And design bracing to those parameters. I did design the cross braces for tension according to the uniform load on the stairs. How is this determined? Is there a method to design bracing to dampen sway on free standing stairs? Any software I can use?






RE: reduce sway in free standing stair system
RE: reduce sway in free standing stair system
RE: reduce sway in free standing stair system
RE: reduce sway in free standing stair system
RE: reduce sway in free standing stair system
RE: reduce sway in free standing stair system
We just got finished designing a hanging stair (fancy finish, etc,) and counted on the stiffness of the concrete filled pans to help with vibration and stiffness. I'm going out tomorrow to view the stair and hope to run up and down and get a good feel if there are vibrational issues. From my vibrational analysis, I don't think there will be, but lets see how it feels.
You have to determine where yuor movement is coming from in order to fix it. If it is the framing of the stair, brace that, if it is the supports of the stair structure, reinforce that.
Let us know either way. These stairs also have little dead load on them compared to concrete filled pans I've usually worked with. Does anyone have any documents how this lack of DL effects the vibrational issues for a typical stair?
RC
All that is necessary for the triumph of evil is that good men do nothing.
Edmund Burke
RE: reduce sway in free standing stair system
RE: reduce sway in free standing stair system
What I'm trying to find out is while I'm analyzing the stairs to code how can I also look at possible swaying, before the stairs are installed and used and someone complains?
RE: reduce sway in free standing stair system
RE: reduce sway in free standing stair system
RE: reduce sway in free standing stair system
For 45' height, there should be several intermediate flies/landings. the columns shall be provided at least at one of the landing, either a simple braced frame (2 legs), or braced tower frame (4 legs).
RE: reduce sway in free standing stair system
RE: reduce sway in free standing stair system