I am evaluating a storage tank concrete foundation and cannot determine a plausible cause for the cracking pattern. I was wondering if anyone had seen a simular pattern?
I evaluated the foundation using a fea analysis and found it adequate as long as the subgrade modulus is about 90 lb/ft^3...
I am working on a project well into construction where a 500,000 gallon tank holding water some 70 feet tall with an alumnium dome roof has had some ice/snow shedding issues. The footprint around the tank is very compact and there has been some insulation on piping that has been damaged. From...
Two additional considerations:
1. Sometimes the generators have short circuit or locked rotor torque that needs to be accounted for to assure the generator does not come off the roof when this upset condition is experienced.
2. For the isolator option the frequencies and limit states of the...
The 7th edition of the Masschussetts Building code specifically addresses load combinations including cranes. And it is free online, if you do a search. Requirements are in chapter 16 under structural design.
You probably should join AUGI and search for answers and post most of your questiosn there. You will find more people use use revit.
You adjust the longitudinal rotation of an element through its properites, though I have found it to be somewhat finiky in RS2009. Sometimes it works and sometime...
As I mentioned, I have only been doing this work for about three years. One of my fellow engineers recommends using a 5 kip point load on every beam in the center for maximum moment. It seams reasonable, so this is what I use. Point load to be concurrent with distributed live load. Granted...
I suggest putting post on Boiler and Pressure Vessel Forum. Requirements would be similar. Those guys could probably answer your question very easily.
My guess is fire code and fuel gas code. But only a guess. I think a lot of it has to do with details, volume of gas, gas pressure etc.
Having done this work for the past couple of years, I can offer some of my opinions on the subject.
1. Plan for at least a 3-5 kip load on every beam, and reduce it appropiately at the columns. The ME's tend to like to hang a lot of stuff off of the building.
2. Plan for the vendor submittals...
Does RISA 3d have the ability to do time history analysis or the equivelant to model and develop the vibration outputs for a given machine vibration input? The machine is a rotating piece of equipment supported on an elevated braced steel structure.
I know it can calculate mode shapes and...
Fema has some guidance on storm shelters.
This can be had at the link.
Maybe only critical items need to be placed in the safe room rather than design the entire building for a torndao.
As others have stated, internal pressures can be come significant for a direct hit by a...
You might want to post your question on the ME Acoustics and Mechanical Vibrations engineering forum. Those guys get really scientific with vibration theory. I would think you would get some interesting responses.
I am currently working on a 80 plus year old powerhouse building for the addition of new equipment. There are many historic shapes that are not loaded with RISA out of the box. I realized I can add shapes individually with the Risa input. But are there any third party applications or freebies...
I have used compression development length in columns for cases where the column will not see tension.
I would agree to be more worried about concrete compressive stress. In a footing the column/pedestal steel would be more confined by surrrounding concrete and I would be less worried about...
Abrasive blast to SSPC-6 (Near white). SSPC-6 requires degreasing with solvents prior to blasting.
Apply zinc rich primer, Apply intermediate epoxy stripe coate to all sharp corners by brush. Apply epoxy intermediate coat. Apply polyurethane top coat. Paint manufacturer's will be glad to...
Get a copy of ACI publication 351.3R-04 "Foundations for Dynamic Loads". Also be sure to get all the information the manufacturer can give you including any special design parameters, as others have suggested.
I agree with previous post. First define the governing code or criteria. However, having said that I know some of the ASME B30 codes for lifting devices call for a FS of 5 against yield and 3 against ultimate strength.
I have been using the Risa to Revit link and on the bi directional cyling I loose my section set assignments in RISA. Is there a way to preserve the section set assignments for the elements that have not been changed on the Revit side?
For example after cyling established, I noticed that the...
