Good Morning Eng Tips,
I`m starting off a new project in an existing building, circa 1975.
I retrieved a joist tag that reads as follows:
24H8 39 11-1/2 (as a stacked fraction) J3
Ceco Corp Pittsburgh PA
I`ve worked with a lot of historic joists and I`m generally familiar with tags, but there...
JAE started a thread about how to handle an unfortunate shear wall location.
I highjacked the thread a bit and started talking about the flexural detailing/stiffness of diaphragms and through it would be best to start a unique thread on the topic.
Some of the conversation is summarized below...
ACI 318-11 section 7.10.5.7 states, "Where anchor bolts are placed in the top of columns or pedestals, the bolts shall be enclosed by transverse reinforcement that also surrounds at least four vertical bars of the column or pedestal. The transverse reinforcement shall be distributed within 5" of...
I`m looking into some modification to a small existing industrial facility that necessitates modifying the existing lateral system/braced frames.
These braced frames are along perimeter walls only, and attached to a pier via (4) 1" dia hooked anchor bolts with 8" embed to the top of the hook...
We're in the early stages of looking at an existing facility that requires new rooftop equipment. Unfortunately, its heavy equipment in a heavy seismic zone.
For gravity loads - the existing structure cannot carry the weight and reinforcing isn't practical. We're planning on dropping four new...
I was recently hired by a client to retrofit an existing building to support their equipment. They're using roughly 1/2 the building and the other half will be vacant for the time being. It's an existing structural built in the early 80s, joist & joist girder construction, braced frames, cmu...
I`m doing some work in an existing building constructed circa 1995. I've measured the existing joists, retreived a joist tag, and know that the joist is a 26K7. From there, it's easy to look up the loads.
Because I`m adding new point loads to the joist (New RTU) I wanted to model the members in...
Along a similar vein as my previous thread is the question of diaphragm deflection between lateral supports.
SDI has a procedure and tons of tables to determine the deflection of a metal roof deck between supports.
In the past, I've considered this carefully in the design and spaced lateral...
I've gotten into some discussions with coworkers recently about whether or not it's appropriate to use only 3 shear walls to stabilize a single story building with a flexible diaphragm.
To create an arbitrary example - say you have a 100' x 100' building with a shear wall or lateral frame on the...
Per ACI, in a concrete column all corner bars shall have lateral support. In addition, every alternate interior longitudinal bar and every bar more than 6" from laterally supported bar shall be laterally supported. (ACI 318-05 7.10.5.3).
For these interior bars (alternate or 6") I've always...
A different post here a couple days ago referenced slab design in accordance with the Eurocode and TR-34. I wasn't familiar with the document, so I wanted to check it out and see how the results compared to other design methods. I've been doing a lot of slab on grade design recently and I...
I was told when I just started working that #4 is designation for deformed rebars and 1/2"Ø for smooth rebars. I couldn't find from codes, is that correct or where can I find this information? Thank you
I know two-way PT slab need to be designed <7.5√fc’ per ACI 318 18.3.3. But no specific requirement limit you design even larger than 12√fc’ as long as you consider some requirement in other parts of the chapter 18: like using cracked section for deflection calculation per table R18.3.3.
Is my...
Checking one project and see Architect drawing says" TYPE 1A with sprinkler, and specifies 1-Hour rating for column and beams and slabs. Is that right? Where is it in the code. I see 3 hours rating in table 601 and know there is reduction for high-rise to TYPE 1B, but still does not see...
if using 100psi minimum prestressing PT as temperature per ACI318 7.12.3, no need for any mild steel in that direction? What to prevent shrinkage cracks before the stressing? Thank you.
AISC 13th Sect J10 has a number of requirements that need to be checked when you have point loads on flanges, including flange local bending, web local yielding, etc, etc.
Most of these can be strengthened with the use of transverse stiffener pairs (perpendicular to the web). Per section J10.8...
To start, I think I've got a solid understand of VQ/I as it relates to horizontal shear in steel beams. I woke up feeling well versed on the subject and spent a couple hours reading some amazing discussions here on this forum.
So here's the question: Has anybody ever witnessed a horizontal...
I've been working as an engineer for the past 7 years, but mostly on large scale commercial & residential projects.
A friend has asked me to help design a retaining wall for his house.
The concrete design is easy, but normally on projects I have a full geotech report to give soil type...
