INCINERATOR STACK
INCINERATOR STACK
(OP)
I need some suggestions regarding the structural integrity of an incinerator stack. This stack I am referring to is 9,000 lbs and 45 feet high with a 48 inch diameter. We have three guy wires that are hand tight with three turns of the turnbuckle. The stack is moving at high winds 12" off of center. The stack is comprised of 9-60" flanged 10 gauge stainless steel. The bottom of the stack where it is flanged to the incinerator is moving and causing bolts to loosen and even snap.
The following are possibilities that we need to look into as to why this stack is such an issue.
1. Wind load to surface area on chimney at 9,000 lb. What moment is being created.
2. If the incinerator starts to rock, will it amplify the movement on chimney.
3. Will it be recommended to have more tension on guy wires .
4. Will the chimney require a lower support structure to brace movement.
Any and all suggestions are welcomed. I am trying to help out a friend.
Thanks,
Louie24
The following are possibilities that we need to look into as to why this stack is such an issue.
1. Wind load to surface area on chimney at 9,000 lb. What moment is being created.
2. If the incinerator starts to rock, will it amplify the movement on chimney.
3. Will it be recommended to have more tension on guy wires .
4. Will the chimney require a lower support structure to brace movement.
Any and all suggestions are welcomed. I am trying to help out a friend.
Thanks,
Louie24






RE: INCINERATOR STACK
The wind force causint overturning is about 70% of the projected area with the resultant located about midheight of the stack if the stack is uniform in width.
Your friend needs to engage a local structural engineer, and soon for reasons of safety. This thing is telling you that it wants to fail.
Mike McCann
MMC Engineering
http://mmcengineering.tripod.com
RE: INCINERATOR STACK
RE: INCINERATOR STACK
RE: INCINERATOR STACK
1. Guyed towers are often designed so that the base is pinned...in other words the base is not designed to resist moment and fixing the base can cause the development of unanticipated stresses in the tower and the base connection.
2. The capacity and stability of guyed towers is highly dependent on having the appropriate tension in the guys. Overtightening them can have effects that are not intuitive including precipitation of collapse. Excessive slack has obvious consequences. Guyed towers are designed for a certain amount of sway and deflection and the guys should not be overtightened in a well meaning attempt to stiffen or immobilize the structure.
RE: INCINERATOR STACK
I agree that a structural engineer should look at it to make sure the guy tension, angle, and configuration is properly matched to the tower, as well as the base configuration.
RE: INCINERATOR STACK
RE: INCINERATOR STACK
Whoever decided to downgrade the stack should have provided a required tension in the guys.
Michael.
Timing has a lot to do with the outcome of a rain dance.
RE: INCINERATOR STACK
Just curious and just looking for a quick practical method.
Dik
RE: INCINERATOR STACK
With a gal.
Mike McCann
MMC Engineering
http://mmcengineering.tripod.com
RE: INCINERATOR STACK
From the sag and the material properties and dimensions. By looking up along the guy, and aiming at something of known dimension, one can get a good estimate of the displacement perpendicular to the theoretical line of the guy, then convert that to vertical sag, and thence calculate the tension.
Michael.
Timing has a lot to do with the outcome of a rain dance.
RE: INCINERATOR STACK
Dik