I have a 1-story Special Reinforced Masonry Shear Wall building where the electrical contractor cut through the diaphragm chord reinforcement multiple times to make openings for conduit. Looking for ideas on how to repair this. The chord steel also acts as horizontal reinforcement for the shear...
Traditionally, a factor of safety of 1.5 has been provided for overturning, uplift, and sliding. The introduction of the 0.6D term essentially applies the factor of safety of 1.67 for you. The unintended consequence of using a 0.6D combination is that the bearing pressure gets hit with the 1.67...
I've got a situation where I'm being asked to expand an existing structure. The existing structure was built with a corbel to plan for future expansion. The only problem is, the existing corbel is not detailed correctly. The anchor bar is not welded, and the ties do next extend 2/3*d down the...
I like PyNite, but I am a little biased, since I created it. I designed it to be easy to use. It covers most of the basics: frame/truss analysis, springs, plates, load combinations, and 3D model rendering. There are examples in the GitHub repository showing how to use it: PyNite Examples.
I'd add that the beam needs to be sized to limit deflection before the concrete has gained strength and composite action is available. This can lead to a larger beam size that doesn't warrant going fully composite.
I'm working on a steel gabled roof design (see attached layout). At the ridge line there are steel ridge beams supported by steel columns. I did that to eliminate/reduce the thrust applied by the roof beams to the exterior CMU walls. I have an attic that acts as a rigid diaphragm (concrete over...
The purpose of the cap channel is to provide lateral support for the compression flange as the crane applies side thrust. In the case of a cantilever, the compression flange is on the bottom, and the cap channel is ineffective. I would treat it like an ordinary S beam.
You have 2 issues to...
Consider a multistory structure with a basement. Assume the geotechnical engineer has given you a soil seismic load against the basement wall. That soil seismic load is resisted largely by the ground floor diaphragm at the top of the basement wall, which carries it out to the basement shear...
MSUK90:
1. I still don't like it - extra unconfined concrete. I hope its not in a seismic region.
2. Expecting the contractor to do a good job bonding concrete to concrete is playing with fire. Lot's of surface preparation and probably some pull-testing required to validate it.
3. Have you...
I would be very hesitant to jacket columns with concrete. First, the concrete outside the rebar cage is unconfined and is the first to crumble and fall off when overstressed. The further away from the cage, the larger the cracks. In high seismic regions you can usually plan on losing any...
You'll be happy to know that the VBA integrated development environment (IDE) has has virtually no changes in the last 14 years, although any ActiveX controls such as buttons embedded in your worksheets may be broken.
Microsoft has been trying to kill VBA for years with no luck. They've used a...
Deker: The OP was concerned about rollover strength of the joists. For diaphragm shear perpendicular to the ridge, the shear is parallel to the joists, and there are no rolling forces. The HSS serves no purpose in either direction unless the deck is dropping diaphragm shear into a LFRS at the...
I think we're over-complicating this. Why are we taking the diaphragm shear through the joist seats at the ridge? Is there a lateral force resisting system running along the ridge? In that case the HSS members would make sense to me, and they would be collectors.
I usually try to avoid a...
What do the contract documents require? 28 days? You can ask for a change, but that's up to the design engineer if 28 days is in the contract documents. A good design engineer will try to work with you, recognizing that they may need to come to you for something in the future. It's a two-way street.
EngineeringEric
This is a wastewater treatment plant building. The spaces on different sides of the wall have different classifications. One side has potential for H2S gas, and the other side is an electrical room we don't want gases getting into.
I have a CMU partition wall with wide flange roof beams over it. The CMU is notched around the roof beams so they can pass over the wall without bearing on it. I need to seal off the spaces on each side of the wall from each other. How do I seal off the pockets around the beam? I can't use...
upuri1213:
I don't have a lot of spare time at the moment to help. I may be able to point you in the right direction if you describe your problem.
ESPcomposites:
Shell elements are challenging to formulate. I've found the MITC4 to be a good element so far, except when calculating stress...
nlgyro:
Are those most recent plots you posted "smoothed"? What does the plot look like unsmoothed? Does it look more like a step function? After looking into it further, I think the MITC4 element may be reporting center stresses at the corners, which explains the divergence at the supports. At...
