Newly Constructed Gym Has Roof Collapse in New Mexico 12

[jerseyshore]

https://www.kob.com/new-mexico/gym-roof-collapses-at-charter-school-sparking-safety-concerns/

ALBUQUERQUE, N.M. — In-person classes have been canceled at a local charter school for the rest of the week after the roof of its new gym collapsed.

School officials say the new gym at the Explore Academy middle and high school campus was basically complete. They were even planning on hosting a ribbon cutting Wednesday, but that’s been canceled, as well as all in-person classes.

Parents learned about the collapse through an email from the school Sunday night.

“The students are out the whole week now,” a parent told KOB 4 anonymously. “Because they have to get inspectors to gather and, at the request of the inspectors in particular, for students to stay away until they can just look the whole thing over.”

The parent said the incident has raised many more concerns about sending her child back to school.

“Students were going to be in that building in two days, and I think one of the big questions I personally have is, did it pass the inspection already?” the parent asked.

The answer is no. KOB 4 spoke with a rep from Albuquerque’s Planning Department. They said the construction company, AIC General Contractors, failed a building frame inspection on March 6. Inspectors found the trusses bowing or bending.

The city’s Planning Department didn’t know the roof had caved in until KOB 4 called Monday afternoon.

Explore Academy leaders say, as of now, it’s just the new gym that seems to be impacted, but they aren’t taking any chances.

“They discovered the damage and evaluated the situation and decided that we would go ahead and go to asynchronous learning until we have a sign off that the entire building and structure is, in fact, safe for students to enter,” said Katia Pride, Explore Academy’s director of outreach.

Pride said there was no obvious damage to nearby classrooms. The school will also have to bring in an engineering company to create a repair plan.

The city’s Planning Department will be sending a building complaints investigator to figure out what went wrong.

 

[Brad805]

One of the most common problems for a failure like this a construction error. We can order OWSJ with mechanical blockouts exactly as pictured. This detail is not all that unusual. In my experience this is for the main supply duct. The duct piled up in the picture would seem to be feeder ducts given the small size. Those would be parallel to joists in the joist depth. To get sufficient air flow for a facility like this I would expect some rather large mains that our artistic friends prefer hidden as much as possible.

 

[1503-44]

Seems like that if the roof broke on the straight line, it would get pulled into that position by the time it hit the ground and wind up just like that. The roof moved laterally right while the truss mostly just moved down. The straight seam looks like it moved south as far as a line between the two windows. During that process, the truss was shaken off it's support bearing. Then the roof broke at the other seam. That side doesn't look like it moved laterally very much. It doesn't look like it hardly reached the edge of the first window. That half of the roof went almost straight down. And it did not make that "V" formation like the other side did. Its almost a uniform slope.
Did not the left roof panel cracked in the center then went down, pulling it off the left truss and , the edge landing quite far to the right, as it orbited downward from a radius at the top of the still intact right hand truss, which finally gives way, going straight down. Yeah. Crack initiated at the left roof center span seems to fit the end pattern. The damaged truss moved laterally left, look at the bearing point left of the wall pilaster. Why would it go left like that, if the left panel didn't go down first, pulling it in that direction?

--Einstein gave the same test to students every year. When asked why he would do something like that, "Because the answers had changed."

 

[Sym P. le]

I don't know why the east end of the south girder moved north as it fell down off its support. Sometimes we get too comfortable using our words and loose our bearings.

 

[dik]

Like Air Alaska... don't you hate it when they don't put the bolts in?

-----*****-----
So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik

 

[Sym P. le]

The north edge of the fallen concrete panels probably landed on a man lift.

 

[1503-44]

Maybe. Looks like there could be a hump there. Regardless, it still looks to me like the direction arrows point to a center of collapse at the left roof.

--Einstein gave the same test to students every year. When asked why he would do something like that, "Because the answers had changed."

 

[Tomfh]

Below is a 2D analysis of a simple pin connected truss showing distribution of tensile and compressive forces.

I may be misinterpreting your output, however it appears you have a pin support at both ends of the truss, with the truss acting as a stiff rope? Both top and bottom chords in tension, near the supports?

 

[Sym P. le]

An interesting observation. Perhaps if I introduce a slight camber it would generate compresion across the top.

 

[hokie66]

No, make one end a roller.

 

[Sym P. le]

A normal instsllation would be welded at both ends?

Edit: Using a roller at 17 generates compression across the top and makes the structure more resilient. That is I have to use a lower modulus of elasticity for 61 to elicit the dip.

With 4x4 support wedgies

 

[3DDave]

If the excess deflection was sag and if, as above, a concrete layer is used to control drainage, then that would make for something of a race condition. More concrete is needed to take out the sag and produce correct drainage than expected. The weight of the additional concrete causes more sag. More concrete is used. Someone says "Enough, we've spent more than expected on concrete. Leave it." and thus leaving a very noticeable sag in the main beams.

Since the hollow rectangular roof beams should be supported at each end, that would also add a sag in the gym long direction which would tend to cause the main beams to deflect to the side and make for a non-uniform loading on the pads.

Anyway, any articles after April 9? I suspect a number of people are crowding the exits and trying to reach the lifeboats before this ship sinks.

 

[Sym P. le]

Using a north facing image of the larger building along with Google Earth, I estimate the gym clear span to be 80 feet. That makes the 16 panels 5 feet wide each and of similar height. A further approximation using the north facing image leads me to believe the top chord buckled at node 4.

Is it possible the vertical compression element coupled with the moment at the lower chord deformed the top face of the lower chord (node 20) and similarly at node 3?

3DDave - if they used topping, you'd be onto something. Since they were only placing insulation on the concrete panels, I don't know if topping was required.

 

[1503-44]

That is ignoring the lack of shear transfer across the open panels.
A lot of the vertical deflection will happen in that open pannel.
It will not look like a rope in tension, but more like a stair step.

--Einstein gave the same test to students every year. When asked why he would do something like that, "Because the answers had changed."

 

[LittleInch]

3D dave - Looks like complete radio silence. A google search with dates other than 9th April just find this site!

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

 

[Brad805]

I would be curious to see the connection between the top chord and the hollow cores. I do not see any studs on the top chord, but the pictures are not great for those details. It seems likely this would be an untopped diaphragm.

The analyses being done are not going to tell us much. There is no question the Vierendeel regions will affect deflections. The question is, does the design work. To answer that would require actual sizes and many other details we do not have access too. The welded joints and sizes would be critical for it to work, but it has been done successfully in endless cases. The stiffened joint pictured previously would rarely be used. They would upsize the vertical many sizes before going that route to save fabrication costs.

 

[LionelHutz]

Therefore, clearly the truss openings were for HVAC duct work.

The units are on the same wall as the ends of the trusses, so the main ducts would run PARALLEL to the trusses across the roof of this gym, not not through the trusses.

 

[dik]

I've seen it done with BAR 3/8x4 welded to the truss with #4 rebar between the HC slabs @ 4'0" o/c. I've also seen it done with discreet BAR stock at 4'-0 o/c with a hole drilled through it for the rebar to fit through. I likely would not use headed studs.

-----*****-----
So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik

 

[jerseyshore]

Some info from the email that the principal sent:

There were aspects of various news reports that were disheartening as they didn't quite get all the facts right, nor were they complete in their information. We wanted to clarify and explain a few details with all of you and provide an update of next steps.
1) The March 6th inspection indicated there was a dipping of the truss that was noted, but the City approved the work to continue - which is why it did. The dip in the truss was still within the expected guidelines. What stopped the interior work was on the 25th of March when the truss had continued to dip. The City required us to hire a 3rd party inspector to check that step of the building plan. That inspection had been ordered but was still pending when the damage started Sunday night.
2) We rely on the inspectors to provide details about the safety of the building. Since we had not had that next inspection, the ribbon cutting was planned to either be moved outside OR postponed, but everything happened on the weekend so we had not sent that communication out yet.
3) The ribbon cutting ceremony is just that - ceremonial to mark the completion of major construction. The work was not yet finished as we needed the gas lines to be activated, the flooring to finish being installed, final inspections to be done, etc. In other words, students were NOT going to be actively using the building this week regardless of the ribbon cutting. The tentative plan was to have them start using the facility until we held the certificate of occupancy. I know it was made to seem that kids were days away from using the building, but that is not accurate on anyone's timeline.
4) On the subject of timelines, on Sunday, at 9:30 PM, I was notified of the damage to the roof. I sent an email to parents by around 10:35 PM, and then someone had notified KOB who then reached out to me at 4:06 AM. I'm sure they were anxious to dig into the story, so yes, they contacted the city quickly after. Communication with the city is something not traditionally done by the school site until we have the certificate of occupancy.
5) Our priority was to ensure the facility is safe for kids. We took our time to do the investigation that needed to be done, so we delayed sharing information until that happened Monday afternoon. We hired an independent engineering firm to inspect the building, and we have contracted with them to remain with the school through the extended completion of construction. This is not typical for these projects, but we wanted to have our own team of engineers hired to oversee the work of the new team of engineers that will be continuing on the building moving forward.
6) To reiterate, there is no apparent damage to the new classrooms, the new theater, new restrooms, or the current building. There also appears to be no structural damage to the gym walls. As stated above, however, we rely on the experts to look into that, and we are unanimous that we need the inspections to be completed on the current building and the remaining new construction before we approve it for kids to return. This will take some time, but we anticipate students returning to the building on Monday.
7)The next steps are for them to inspect where the facilities "neighbor" each other. The new construction is a separate, divorced structure with space between the older facility and the new facility. They want to inspect what connects the building from the top and to ensure no damage was sustained to the structural integrity of the walls in the new building. They are working on that today. Following that, there will be a plan to shore up existing walls in the new building before we move kids into the old one. This will ensure students are safe to return.

 

[jerseyshore]

And some notes from their Zoom meeting. Seems like they aren't revealing much. Need someone in NM to pull a public records request for us to get the plans.

School Leader Report (Jake Kolander)
David Shaffer - AIC General Contractor
Doug Majewski and Wendy Caruso, Design Group NM
Facility/Construction
Gym roof
Mr. Kolander thanked the parents who have reached out. He explained what occurred on Sunday evening, which was triggered by an alarm. School administrators, ELS team members, and Mr. Shafer reported on site immediately to see the damage. The team is waiting for details before putting out information to the community to ensure accuracy. He further noted that the facility was not complete and was not ready for occupancy. Final inspections had not been done and no students would have been in the gym until final review and the certificate of eOccupancy was issued.

Depending on third-party inspections, the main building is expected to be open for students on Monday. This does not include the classrooms and gym in the new addition. If official written assurance of safety is not received, the building will not re-open.


Mr. Shaffer expressed agreement with Mr. Kolander’s comments; he complimented Justin Baiardo for quickly arranging a third-party inspector on behalf of the school. He confirmed that the life support systems are separated from the main building.


Mr. Majewski also agreed and advised that the team is awaiting results of the inspections and investigation and will take the appropriate steps to complete the project.


Ms. Caruso expressed that we are working as a team and that there will be no rush as safety is a priority.

PUBLIC COMMENT regarding items not on the agenda
The floor was opened for public comment.
Steve Rowan commented that he will gladly provide guidance about the expected weight load for the black box theater ceiling.
Joe Graziano commented that “the roof is a spring cable suspension system with concrete beams and poured concrete as the material over styrofoam. There is no way the cable system failed. Those walls are under tension right now and are dangerous to be near. I just need assurances that the state inspectors are on the case but the building needs to be removed and rebuilt. The school appears to be ambitious with returning. Thanks.”

 

[3DDave]

It is poured concrete over the concrete beams.

This is very like the New York bridge with the unbraced kink in the upper flange; I bet someone thought this job was too simple to bother to analyze because "just look at how big those girders are."

That no one said, let's get some shoring until we can figure out why it is sagging, is a head scratcher.