I've always tried to avoid detailing a tube beam welded to the face of the two supporting columns because I feel like this creates a difficult tolerance window and constructability issue. Even if the steel is manufactured perfectly, field installation of the columns could create a situation...
Architect wants to cut new doors and windows in existing panels. I've never dealt with this issue before and want to hear some sound engineering advice. In theory, the portion above the opening just becomes something of a really skinny deep beam spanning between columns that are the full height...
I work for an A/E firm and often encounter both sides of this coin. We are retained as both the structural engineer to design shell buildings where no mechanical equipment information is available, as well as tenant remodels of existing buildings for which new mechanical equipment loads are...
I was taught to treat a structure's horizontal diaphragm(s) as if they were bending members (beams) being loaded by wind or seismic forces. I have always been more inclined to obtain forces by using "beam theory" equations as opposed to just "using the trib".
Imagine a beam with three...
I got thrown into the fray of an RFI fire drill where the contractor working on a renovation project found an existing steel column displaying corrosion near the base. The bottom of the column is still encased in concrete/topping and not exposed. It appears that the corrosion occurs up to around...
I have been laboring under the interpretation of Registered Design Professional in Responsible Charge (RDPiRC) of special inspection as the person who is literally in charge of all aspects of the process (i.e. determining the special inspections required and their required frequencies...
I can find published formulas for the critical deflection of a continuous beam with a uniformly distributed load and equal spans (wl4/185EI); however, I would like to know if anyone has ever taken the time to derive an equation for a two-span continuous, uniformly-loaded beam with unequal spans...
ASCE 7-10 - 27.4.5 states that pp is the combined net pressure on the parapet due to the combination of the net pressure from the front and back parapet surfaces. The coefficient GCpn is depicted at the net pressure coefficient and is equal to:
= +1.5 for windward parapet
=-1.0 for leeward...
Trying to run some prelims to win a bid for an site expansion so I don't have tons of info. Part of the expansion is to add parking below grade and use the deck as tennis courts. I feel that the closest category in ASCE7 is the "bowling alleys or other recreational areas" at 75psf. I feel this...
If the soil bearing is high enough, one could encounter a situation where the pier will not fail the soil in bearing before is surpasses the Pallow obtained from treating the pier as a concrete compression member 0.8Φ[0.85Asf'c(Ag-As)+AsFy]. Is column axial failure a factor in drilled pier...
When I have designed straight shaft piers in the past, I've added what is basically uplift using the compression SF to the allowable load obtained from Ag*σallow since that compression skin friction is adding to the pier's resistance to applied loads. (i.e. Pallow = Ag*σallow*(Π*D*(penetration...
I have always had an issue with my company's lack of detailing the interaction (or what I think should be a lack thereof) of floor and roof trusses passing over non load bearing (NLB) walls. We dictate which walls in a structure are to be LB and, without making any special recommendations, seem...
I hope I am not thinking about this situation erroneously but I want to know if there is a combined effect for a beam that will be loaded in two axes. The situation I am dealing with involves a cabana structure with a gable roof and half height walls. One of the methods I came up with for...
Steel folks asked if they could downsize the steel angle listed in our lintel schedule and I am trying to run the numbers and finding out I have a lot of questions. Section F10 states that the nominal yield moment is 1.5My. Thats definitely not hard to do unless you aren't sure what My is. The...
We are dealing with the ever-increasing issue of brick veneer climbing higher than the typical 30ft max of yesteryear and it is causing our company to look into our designs to find out what we can be doing differently for these special cases. I am looking into deflection of wood studs backing...
According to 10.5.4 (318-08) As-min for footings of uniform thickness shall be the same as that required by 7.12.2.1 (0.0018bh) and the commentary section R7.12.2 states that this area of reinforcement may be distributed near the top, bottom, or allocated between the two faces. I was using a...
I am attempting to design a safe room for a school. The safe room is a new structure that abuts the existing structure at one corner. Due to the building "overlap" a drilled pier cannot be installed at the corner of the safe room that abuts the existing structure. Imagine a rectangular building...
I am designing a small multi-purpose/safe room and ran across an issue. I obtained some calcs from an old job that were done by an engineer that no longer works for my company in order to check my work against hers. I noticed in the C&C section that when she calculated the areas for zone 1, 2...
Has anyone ever come up with a simple solution (simple in terms of construct-ability in the field) for a situation in which the ceiling joists and roof rafters need to be connected (preferably over, or at least near to the wall supporting them) but are to be at a different spacing?
Somewhat new to wood framing design so I apologize in advance if this is an elementary question. I am attempting to calculate the combination load effects for a stud wall with sheathing on both faces (exterior plywood sheathing and interior gyp-board) and would like to know if the column...
