I'm looking for some opinions and approaches for methods of calculating wind loads on conveyor trusses and more specifically the arched belt "covers" that are sometimes attached to the truss. See the pictures for what I'm talking about.
Currently we are using ASCE 7-10 Figure 27.4-3 for...
Hello all,
I am working on the design of the structure shown in the attached sketch. I have modeled the structure and done a second order analysis in RISA 3D. I don't have any issues with the model stability but I am trying to verify the global buckling with a hand check. For each mast I...
I'm looking at the following scenario, conceptual sketch attached. A conveyor is pinned at the tail and will be inclined/declined using a winch and wire rope system. The wire rope will attach at at least a couple points along the conveyor and will be supported from a central mast that will...
Has anyone "designed" a hanger like shown in the attached sketch? I've seen them used occasionally in mine processing plants but I assumed they were just remnants of decades old practices.
I've been asked to use this concept to support a walkway stringer from the bottom chord of a box truss...
**I considered posting this in the Mechanical>Acoustics & Vibration forum but I think I'll get more input here. I'm looking for any opinions/experiences but specifically from structural engineers if there are any.**
I've recently started looking into motion amplification camera technology to...
I'm looking for any references or guidelines on acceptable vibrations for industrial structures. I see plenty of charts and resources for the machinery but most of those are aimed at limiting bearing and shaft failures. Using criteria for an occupied office building seems to conservative as...
Hello all. I am looking for some tips on determining the natural frequency of a structure supporting a vibrating screen during coastdown. My understanding is that I can measure the machine speed over the duration while simultaneously measuring the displacements of the structure. I currently...
I know this has come up on the forums before. Specifically, this thread addressed some concerns serious concerns with the force transfers in stepped retaining walls.
https://www.eng-tips.com/viewthread.cfm?qid=459064
I'm designing a wall and want to use the tapered geometry and direct lap...
Hello,
I'm looking for a sanity check on a concept I'm working through. In the attached sketch, will I be getting five times the line tension lifting at each bottom corner?
Also, is there a preferred pattern to lace the cables through the sheaves for something like this. The lower sheaves...
I'm going to show my ignorance here, but suppose I have a hydraulic cylinder that has a total stroke of 100 inches and I only need to use 50 inches. Is there a way to limit the stroke hydraulically? Trying to avoid travel limit switches if possible but I don't want the cylinder to extend past...
I am looking at a bulk material storage bin and thinking about the many cycles of loading and unloading. Suppose I have simple span floor beams with a "floor" plate bolted to the top flange of the beams. What case would be appropriate for the fatigue checks on the beam at the bolt location...
Crane collapse in London. Not clear if any fatalaties but it doesn't look good. A lot of detail in the Youtube video.
https://www.bbc.co.uk/news/amp/uk-england-london-53339296
https://www.youtube.com/watch?v=FGoOZPAe78s
It's been years since I had my physics and fluids classes but I finally need them now. Problem is I've apparently forgotten the little I learned.
I have tank that can have water overflow at a given rate. Tank is open to air pressure at overflow location. I need to size a pipe to handle the...
I'm looking for any design criteria for superstructures of inland river barges. I am not designing the barge, only the processing equipment and structure that will be on the deck. As a preliminary design I have treated it as a normal static design. Would doing the same for seismic load be a...
I'm looking for thoughts on the situation shown in the attachment. A structure supporting a reversing conveyor. The structure will become engulfed in the crushed stone stockpile. What type of lateral pressures would you use? My initial approach was:
1. Assume only one stockpile in place.
2...
I'm looking for some tables similar to Roark's or Moody that deal with the triangular shaped retaining walls or flat plates, fixed on two edges as shown in the sketch. Does anyone know of such resource...
This is a foundation for a large aggregate bin and crusher. Contractor is planning on using the blocks as spacers for top and bottom mat. We are saying no. Has anyone else seen this method used before? I'm also not thrilled with the bottom mat support but it doesn't bother me as much as the...
Anyone care to describe how they handle wind load combinations when using RISA3D and RISA Foundation? Specifically, do you use two separate basic load cases for the two different roof pressure values? Seems like the only way to keep the roof wind load separate so that it can be added to load...
I'm curious how everyone handles designing structures around vibrating machinery. For example, in the situation shown in the attached sketch. I have a small structure supported on a larger structure that also supports a large vibrating screen. The screen weighs about 93,000 lbs and operates...
I have a conveyor support on a structure that supports a vibrating screen. See attachment. There is a vibration damping pad between the support baseplate and the main structure. I'm still seeing a some vibration in the longitudinal direction. I know it isn't ideal, but would bolting (welding...
