I'm modeling a continuous beam that has 5 spans and the end spans are cantilevers. When all of the spans are equal, the moment at the first supports from the ends from Risa are correct. That is they match the moments calculated using structural analysis; w(l^2)/2.
When the end spans don't equal...
I am using Bentley's Conspan to design a voided slab superstructure. I am trying to find out why the Service I self-weight deflection doesn't match the deflection due to the self-weight load case, or my hand calculation.'there should be no factors applied for Service I. I have stripped off all...
Sorry about that. I am looking in the NY, NJ, CT tri-state area, but if there is
a particularly good fabricator, then travel is not an issue. Quality is
the most important issue.
thanks
I am looking for a very good shop capable of high end fabrication of stainless steel architectural metal work. Five-axis cnc type of work. Any suggestions on where to look?
Thanks
Thanks structSU10. Risa is working pretty well, but the difficulty is trying to model the rubber bumper
connections of the glass top to the base members. I feel it is incorrect to connect the glass plates directly to the base. I've been using a very short link model with the properties of...
I am analyzing a table for a friend that has a base made of 3/4" diam. steel bars, with a 1" thick glass top. The base consists of one piece of bar that has many 90 degree bends, and stability may be an issue. Risa 3D and other programs can do this, but I was wondering if there is software out...
I am trying to understand the provisions of ACI Appendix D (318-08), specifically Section D.6.2.9 on anchor confinement reinforcing. To me, the code doesn't specifically state how to design the confinement steel, but states the steel must be developed in accordance with Chpt 12.
I checked in...
I am determining the base shear for a single story structure and someone told me that I shouldn't include the parallel wall weights in this.
I also read in the Structural Engineering Reference Manual, 4th edition, Diaphragm Load Section that the seismic weight tributary to a diaphragm should not...
I am designing OMF connections using the Seismic Design Manual, for an R > 3. The thing I'm confused about is the required shear. Section 11.2a of the Provisions states Vu or Va must be increased by the seismic load effect, E = 2[1.1RyMp]. Page 4-3 of the Manual shows the same value but in the...
I've been designing some cmu lintels and some configurations I need are not in Table 4 of TEK 17-1B. I created a spreadsheet to design my lintels and checked it against the Table 4 values. What is strange is some Mresisting values match and others are off by a significant amount, say...
Can someone tell me why RAM computes a negative moment capacity for a beam using the composite properties? I checked the documentation and it does use the composite properties if the moment isn't greater than 2x the positive moment.
Unless I'm missing something, the code states that the...
Seth,
Thanks for your response, but your response leaves me with a couple of questions:
My case is the one with braces that by-pass a level, because there are no diaphragms at those locations (I have multiple diaphragms, at different levels). My question is, based on how RAM is determining the...
I have a model with multiple diaphragms at different levels, but also at different locations in plan; it is an "L" shaped structure. With the various stories, I have columns that RAM treats as segmented at the different story locations. The problem is the little segmented column masses are not...
Seth,
I have another question if you don't mind. What am I missing with modeling cantilevers? It seems that I can't model a cantilever with a simply supported beam in the backspan. Am I missing something?
Thanks
Gumpmaster,
Thanks. I realized after I replied to Seth's post that the rho override takes place after the analysis, which is why I was seeing the calculated rho values.
I wish I could upgrade but it is not my company. I have to say I find it very difficult getting around in RAM and checking...