I contacted APA. They emailed to me a document called "Introduction to Lateral Design" which discusses how to deal with ridge vents in roof diaphragms. For unblocked diaphragms there is no issue because there is no requirement for connection to be made between unsupported edges of...
BOO1,
I haven't seen it (or specified) it either. That's why I asked the question - I was wondering if omitting the plywood at the ridge vent was actually a problem. Can the truss transfer the forces across the opening? I sent an email to APA asking this question. I will let you know if they...
The other half of the problem is what to for the other direction. The diaphragm that resists the shear from the gable end walls is also in two pieces. The problem at the ridge is that I don't have a shear wall running down the middle of the building to resist the drag forces transmitted from...
Is the solution to design two "sub-diaphragms" and put blocking along each edge of the ridge vent? The blocking would also be diaphragm chords and will be designed for tension.
I am analyzing a large 3.5 to 12 roof as a plywood diaphragm. I realized that there will be a ridge vent down the center of the diaphragm that will essentially cut the roof in half (a few inches of the plywood will be removed to provide the ventilation at the ridge vent). Does this cause a...
I am designing a two-story house, mostly for wind load. I am having difficulty establishing a constant lateral load path from the roof to the ground. I am looking at a system of a wood shear wall at the 2nd floor (supporting the roof) and a steel moment frame below, supporting the 2nd floor...
Qshake,
Thanks for you response. I have also asked this question to AISC and they said that it is not considered composite according to latest codes. One book that I have that deals with structural renovations, suggests coring the slab above the beam and welding shear studs to the top flange...
The project consists of adding new ceiling hung medical equipment on the ground floor of a hospital. The building was apparently built in the 1920s, and of course there are no as-built drawings. The existing floor framing above consists of a concrete slab supported on steel beams. The...
We did some measurements on an existing building that was to be expanded vertically. The new steel beams (W8x24 spanning 17 feet) were to be supported on one end by new steel columns spliced to existing columns and at the other end on an existing brick wall. Unfortunately our measurements came...
There is an article in Modern Steel Construction magazine (November 2001, published by the American Institute of Steel Construction) about designing HSS connections. This article referred a publication called "Hollow Structural Sections Connections and Trusses - A Design Guide", by JA...
I am designing a 4-story steel building (100'x100'). The first phase of the construction will only build the first 3 stories. What type of provisions should I make for the future story? It is unknown how far in the future the 4th story will be added. Thanks.
This is a great forum going here.
I also think STAAD leaves alot to be desired. I am currently trying to use it to analyze a steel building. I created the original file with STAAD Pro 2000. I now have the latest STAAD Pro 2001 and it crashes when I try to open the original input file. The...
I have designed a foundation to support a large piece of equipment. The machine manufacturer recommends extruded polystyrene insulation for the vibration isolation joint around the perimeter of the foundation. The machine manufacturer states that the machine vibration is 10 Hz. Has anyone...
