Resolving Forces and Sizing Profiles in Structural Engineering

AI Thread Summary
The discussion focuses on resolving forces and sizing profiles for a structural frame supporting a 32,000 kN pipe. The user is facing inconsistencies in force calculations across different members, particularly between members M20 and M10, and seeks methods to ensure balanced results. Suggestions include using matrix inversion for load calculations and employing space frame software for accuracy. Additionally, profile sizing should consider tension, compression, and buckling potential, with an emphasis on reducing section sizes for efficiency. The importance of understanding load transfer and the implications of plastic design in steel structures is also highlighted.
Gunter1977
Messages
6
Reaction score
4
TL;DR Summary
Frame members
I'm with a home study structural engineering as an electrical engineer. The assignment that I am trying to do is calculating a frame to support a large pipe with a weight of 32,000 kN distributed across eight legs. ( so it on a job site) I've performed a detailed analysis of the forces using free-body diagrams and resolved the components for each member, as shown in the attached PDF. However,

I have encountered challenges in achieving consistent results across all members, particularly in balancing the sum of forces and moments. For instance, while I've determined the axial force in member M20 to be 5072 kN,

I'm struggling to achieve the same consistency for member M10.

Questions:
1. Method for Resolving Forces:
How should I approach ensuring consistent results across all members? Are there specific methods or techniques I should consider to balance the forces and moments effectively?

2. Determining Profile Sizes: What factors should I consider when determining the sizes of profiles (beams)? Is it primarily based on considerations of tension, compression, or potential for buckling under load? I appreciate any insights or guidance on these issues. Thank you!

Thank you in advance,
 

Attachments

  • Like
Likes DeBangis21 and berkeman
Engineering news on Phys.org
1. Consider solving the loads as a matrix inversion, rather than sequentially, individually. Use space frame software.

2. Refine the design by changing, (preferably reducing), the sections based on tension, compression, and column stability (buckling).

What gives? Plastic design of steel structures, allows the material to bend when first installed. Do you want the pipe or the supporting frames to deform first? By designing the frames to deform, until the load is cradled in the structure, there will be significant savings in weight and cost.
 
I believe that the free body diagram is very far from reality, as the lateral forces are non-existing, unless an external horizontal force is acting on the tank.

The only external forces acting on the support are the equally divided weight, acting solely in a vertical direction.
How the different members transfer those loads to the ground is a different matter.

Therefore, the represented four blue vectors seem to be incorrect.

Tank support.jpg
 
Last edited:
How did you find PF?: Via Google search Hi, I have a vessel I 3D printed to investigate single bubble rise. The vessel has a 4 mm gap separated by acrylic panels. This is essentially my viewing chamber where I can record the bubble motion. The vessel is open to atmosphere. The bubble generation mechanism is composed of a syringe pump and glass capillary tube (Internal Diameter of 0.45 mm). I connect a 1/4” air line hose from the syringe to the capillary The bubble is formed at the tip...
Thread 'What type of toilet do I have?'
I was enrolled in an online plumbing course at Stratford University. My plumbing textbook lists four types of residential toilets: 1# upflush toilets 2# pressure assisted toilets 3# gravity-fed, rim jet toilets and 4# gravity-fed, siphon-jet toilets. I know my toilet is not an upflush toilet because my toilet is not below the sewage line, and my toilet does not have a grinder and a pump next to it to propel waste upwards. I am about 99% sure that my toilet is not a pressure assisted...
After over 25 years of engineering, designing and analyzing bolted joints, I just learned this little fact. According to ASME B1.2, Gages and Gaging for Unified Inch Screw Threads: "The no-go gage should not pass over more than three complete turns when inserted into the internal thread of the product. " 3 turns seems like way to much. I have some really critical nuts that are of standard geometry (5/8"-11 UNC 3B) and have about 4.5 threads when you account for the chamfers on either...
Back
Top