I was asked to design a special concentric braced frame (special Concentrically Braced Frame in seismic design category D, with R=6). it's a one story X-brace with HSS squares as diagonal braces. the height of column is about 14' and span of beam is about 29'. Beam and columns are typical...
I am working on a project with 2.5" NWC on 1" non composite metal deck (total of 3-1/2" deep) supported by steel open web joists at 2'-0" OC.
Do we need to specify saw cut joints on the concrete. the floor layout is about 180'x120'. Thanks.
I am working on a cold-formed steel bleacher framing and want to design diagonal braces. I wondering how much lateral load we should use for such structure
10% of live load? any reference for that? Thanks
we are designing a two-way PT slab for a parking deck.
The typical span of slab (distributed tendons direction) is 30 ft
at the pour strip, we have two conditions.
At first condition, there will be a 18 ft wide pour strip. So the overhang of slab from each side is about 6'. at this, the tendons...
for single story building, I have load bearing CMU walls and typical roof open web joists sit on top of CMU walls. The metal roof deck (unfilled with concrete) sits on the joists as diaphragm.
It seems the wall can restrain the Z direction but not the X, Y direction. So when I have seismic...
we are designing a generator platform. According to the code, the weight of generator will be increased by 20% or 50% to consider its vibration.
If there are vibration isolators under the generator, can we reduce that impact load? do we have any design guide/reference for that load?
Thanks.
We are designing a one story specially moment frame. what should we need use to design the column footing (shallow, spread), load combination with amplified seismic loads, or typical load combination?
Thanks.
We are designing a specially concentric braced frame. I understand the connection of braces shall be designed for the expected yielding strength of brace or maximum possible load for the system. In our case, the brace is connected to the column and base plate through gusset plate, then to base...
We have calculation sheets (*.mcd) developed with Mathcad 2000. But those files can not be open with Mathcad prime 2.0.
Does anybody know how to do the conversion? any suggestions?
Thank you so much
We designed some shoes/anchors for gasoline pipe. a bunch of steel plates are welded together and then welded to the pipe. One of reviewer's comments is "new compliance calls for a four corner cutout/weld. As shown it would appear to be four point weld". I do not understand what that is.
Can...
I am calculating wind loads for an open structure roof. I use equation 6-25 p=qhxGxCn of ASCE 7-05 section 6.5.13.
The Cn net pressure coefficient shall be determined from Figs 6-18A through 6-18D. But All those figs have the requirement of 0.25<h/L<1.0. In my case, h/L is 1.33. Is it going to...
We have specified mortar mix strength of 1800 psi. But for several times, the field test data shows those mortar sample has only about 1200 to 1500 psi per ASTM C780. I checked online it seems a quite common situation.
Can anybody have some reference for that? What is minimum strength we can...
We designed a cold-formed steel stud shear walls with Simpson HD holddowns. We use Simpson SET-XP epoxy for the threaded rod as the anchor bolt of the shear walls.
Today I got a question from the field guys. After the epoxy hardens, they tighten the nuts for the threaded rods. But they use 90...
we want to verify that the welders working on one project are AWS certified welders. So do they have welder certification cards or welding test records we can check?
we just want to make sure those are qualified welders.
Thanks.
For one project, we want to use AISC certified steel erector. but the GC says there are only three companies certified in their state and all of them are not intrested in the job. The GC want us (engineer of record) to waive this requirement.
I am thinking if we waive the requirement, shall we...
We are doing some repair work. The existing I shape beam has a web of 3/16" thick. We are going to weld a continuous L6x6x5/8" angle along the web (the driection of the angle will be parallel to the web)
we specified 1/8" fillet welds 4" long @ 12" OC for the connection of vertical leg of the...
We are working on a repair project for aluminum hand rail in swimming pool area.
We want to coat the boots of hand rail posts to prevent corrosion. At the beginning we specified Eoncoat, but we were told Eoncoat is only for steel.
Any suggestions. Thanks.
we are checking a concrete floor built in 1974.
The current load combination is 1.2DL+1.6LL from ACI 318.
I am wondering what they used in 1974. 1.4DL+1.7LL?
we do no have a copy for ACI318 1971. Can anyone help me out?
Thanks.
The pier (pedestal) of concrete footing is exposed to weather (in cold area). But the air content from cylinder test shows that there is only 3.5% air content. We want them to have 5-7% air conent.
So What's the best way to deal with this? is 3.5% acceptable?
It's will be very expensive (and...
I am going to design a 2-story office steel buidling (probably moment frame, colum base may be designed as fixed).
I am wondering if there is a FE software can design the steel building frame (column, beam), base plate, anchor bolts, concrete footing for columns, and check the soil bearing...
