All,
The owner and architect want to place a standing seam metal roof over an existing conventional bar joist and metal deck roof system. The slope of new roof would be parallel to the joists. Joists span 45', are spaced 4' oc and have panel points about 4' oc. Narrow rib metal deck with 5"...
We are rehabbing a 130 year old courthouse. The roof framing clear spans about 50 feet over a central core using 7' to 9' deep girders built up of 1x12's. The webs are two layers of 1x's (flat) diagonally opposed to each other. The chords are then nail laminated to them and consist of 6 or 8...
I am to get to play with Ricardo's Wave program a few days in the next couple of weeks. Any words of wisdom? Would anyone have input files for SBC engines that could be shared? I am assuming that each component will need an input file to model it, ie. cams, head ports, intake runners, intake...
The IBC Existing Building Code uses the term "in high seismic zones...". I connot find a definition for that in either the existing building code or the main IBC. What am I missing? Thanks.
I am designing the foundation for a minor tower. The specifications included design of ice loads from ASCE7-02. When I use eqn 10-1 to calculate the area it seems excessive. It takes a length times a width (a rectangle) and then multiplies it by pi. I understand pi*D^2/4 as an area but the...
We have a client who's elevated slab on metal deck and bar joists is cracking. Thankfully it was not our design. It appears to be shrinkage cracks but I cannot find much information on control joint locations for elevated slabs. Any help or direction to authoritative source would be...
We are preparing a Critical Lift Plan for an 88T pick in a conjested area. The erector's contract required a sealed plan. No problem doing the work but we are not sure what to charge. It seems like the liability is disproportionate to the hours of work. Any guidance? Thanks
I would like to build a SB Chevy engine to run as an Atkinson cycle engine. By Atkinson cycle I am referring to high compression with late intake valve closing. Pump premium gas. I am willing to live with reduced power output for a slight increase in efficiency. Can anyone provide a starting...
Can anyone recommend a good book or other source of info on the Miller Cycle engine? As I understand, it is simular to the Atkinson Cycle (less the complex mechanism) engine but with a pump to get the specific HP back up. Thanks
Is there something that I can coat the "back" area of clutch slave and brake cylinders with to reduce corrosion? It seems the boots do not keep out all moisture and condensation on vehicles that are use infrequently. Thanks for any help.
I am designing segmental retaining walls on a project. One portion of one wall skirts a retention pond. The NCMA design manual throws up a lot of red flags regarding "Submerged SRW Design" in section 8. Other designers feel that if backfilled with free draining granular material the water...
In the late 70's or early 80's Bruce Crower developed a kit for the 350 SBC that reportedly improved mileage significantly. It used a very high compression ratio combined with late intake valve closing. The theory being less throttling losses, less compression stroke, higher expansion ratio...
I am analyzing an existing PEMB. It looks like a typical PEMB. 25' bay spacings, 2/12 slope, 150' span, all tapered plate girder type members, 8 1/2" deep Z purlins, late 1980's construction, etc. In my analysis the columns show a higher stress than the girders. Also the depth of the...
Past threads have commented on the high unbalanced snow load of ASCE 7-02. It has been reduced in 7-05. In my case the 7-05 magnitude is slightly higher but it only applies to a narrow strip on the windward side of the ridge. Does anyone have any history on this change? I would like to...
A client needs to add ceiling loads to an existing PEMB. No drawings were available so we measured everything up and ran it on a frame program. As expected the interaction equations (code checks) came out near one. I gave myself a pat on the back for the good modeling effort.
Now the hard...
I usually hang around on the structural forums but I hope no one minds me asking for help here. I am looking for a good book on Holley tuning. I have a kit car with a fairly radical SBC engine (250+ degrees duration at 0.050 lift). It runs fine at the track and so so on the street but I think...
Does anyone have a catalog or other info on "4 inch Stran Steel Studs @ 16" c.c."? This is the callout on some 1948 drawings for a building that we are rehabbing. In this particular case they are load bearing wall studs supporting a bar joist roof system. Thanks for the help.
We recently started working for a contractor that specializes in Pre-engineered Metal Buildings. We provide the foundation design based on soils information and loads from the PEMB manufacturer as well as other features from the architect. The first couple were cake.
With winter approaching...
In the 2002 AASHTO Standard Specification for Highway Bridges, Eqn. 16-27 the thrust Ns times a factor is added to the moment Ms in determining the stress in the reinforcing. This stress is used to check for crack control. By definition these terms are added when the trust is causing...
