This is a feature of a 36′ dome that was built by Monolithic in Temple, TX. This dome is unique because of its tube entryway and inset shower.
The floor was poured onto white rock road base, which made it hard to dig and form. Once we got the footing dug, the rest fell into place very nicely because the owner did such a good job by providing a level job site. Since this floor was being inspected, we were required to put plastic underneath the floor.
After the concrete was poured, and the uprights were bent down, we attached the Airform, using stainless steel straps and stainless steel Rawl spikes. The reason we used the stainless was that we were going to pour concrete against them, and the owner was worried about the concrete eating away at the galvanized straps that we usually use.
The tube entry was inflated with the dome and turned out really well. Javier was able to use plywood to form a doorway into the entryway. Javier sprayed the tunnel and one side of the plywood with concrete, then he removed the plywood and sprayed the other side.
We had the Monolithic Dome Convention this weekend, and there were a lot of people that weren’t able to come to it. I have taken my presentation and made it into a pdf available for download.
My presentation was about equipment. I kept it fairly general except for the new Paxis Scaffold. Go through it, and if you have any questions, just ask them in the comments and I will answer ASAP.
You will hear a lot more about our new Paxis Scaffold in the future on Monolithic.com, but in the meantime I will post some raw video clips. It’s hard to describe how nice this scaffold is, but with the new drive motors and the 10′ stance, this scaffold makes one of the sturdiest, safest platforms I have ever seen.
It has been a very busy couple of weeks for me, and I apologize for not posting these pictures sooner.
The new paxis scaffold was a huge success, even though there are a few things that we are going to do differently. The one thing that we didn’t expect, was that it was so heavy that it started to make some pretty substantial ruts in the ground. We have been toying around with a few different ideas. First, I think we will pour a concrete circle in the middle of the dome so that the pivot point and tires have a harder surface to rotate on. Secondly, I think we will try to find some wider tires for the outside wheels, and change the way the motor is mounted so we have more ground clearance.
The dome construction went very well. The foam and rebar hangars were uneventful. The one thing we did a little differently was hang about a quarter of the steel on the bottom 20′ of the dome, then spray a half inch of concrete. The reason we sprayed that concrete was to help prevent all of the #6 bars that we had to install on the bottom half, from pulling down on the foam too much. The weight on the rebar hangars will sometimes cause the rebar hangars to pull away just a little, but it’s enough to make the outside of the dome have pucker marks. The concrete spraying went well, and the dome looks very nice.
After we got done spraying the dome, we sprayed the foam on the stem wall. We started by spraying our Monoform primer onto the wall first, and then spraying two inches of two pound foam. Now that the dome is done, and the foam is sprayed, we are going to remove our scaffold and let the plumbers and electricians in to do the underground work. Please enjoy the new pictures, and look forward to more blog entries in the future.
Now that we have used our new polar scaffold for a couple of weeks, we have reports from the crew that the motor is still running a little slow. So, this is what we’ve done.
Original Scaffold
Current Motor
New Motor
Gear Box
60:1 Gear Box
60:1 Gear Box
30:1 Gear Box
HP
3/4 HP Motor
3/4 HP Motor
1 HP Motor
Drive
MD-60 Drive
MD-65 Drive
RPM
Electricity
110v Single Phase
220v Three Phase*
220v Three Phase*
* The drive unit is 220v single phase, and puts out 220v three phase. So it should work on any jobsite.
Just in case you haven’t read the first article, we are switching from the single phase to three phase powered drive system so that we can have adjustable speeds. The longer the scaffold, the longer it takes for one rotation. For instance, spraying consistent concrete at the end of the scaffold might be just the right speed, but spraying towards the middle will be a lot harder with the slower speeds.
The biggest difference is the drive. The original drive that we used had most of the same features that the new one does, except the ability to drive more power to the motor. The new MD-65 has the ability to increase the frequency of the power. So instead of adjusting the power from 40 hertz to 60 hertz, we are able to go from 40Hz to 120 Hz. I use the number 40 Hz for the minimum, because if the motor turned much slower than that, the motor wouldn’t be able to cool itself. I adjusted the drive to 120Hz for the highest setting, because I was concerned that any faster, and we might have to install seat belts on the scaffold.
The only remaining worry is that the increase in speed will decrease the power. Enabling its ability to climb over objects like pipes and rocks in the dome, but I think we have overcome that with the powerful new drive motor. Javier is going to take this scaffold motor with him on Monday, and I will post a report on its progress. Thanks for reading.
After an extremely windy day of attaching the airform yesterday, Javier and his crew had the dome ready to inflate by the next morning. This church is using a copper colored airform that looks great with the limestone colored stem wall. We started the inflation at 9:30, and at 9:40 it was all done. Father George and a handful of the parishioners came out to see the dome inflate.
In the picture gallery you will notice the dome has kind of an egg shape. On the next pictures, you will see the dome round out a lot more. Patterning the airforms is something that has taken us a lot of years to perfect, and it is interesting how we have to pattern them in a weird shape, so that when it’s been inflated for a day and done stretching, it will be the desired shape.
Now that the dome is inflated, Javier is going to finish building our new Paxis Scaffold. The next step is to mask off the uprights. The uprights are the pieces of rebar that extend from the wall, and will be tied into the dome’s structural steel. Once the steel is in place, and the electrical is installed into the shell, then we can start spraying concrete. We expect to start spraying foam on Friday. You can see more pictures of the inflation here.
Again we are making good progress at the St. Joseph Catholic Church in Commerce, Texas. We finished the blocks last week and started to form the ring beam for the top of the dome. Despite the rain and concrete pump problems, Javier and crew got the forms finished, installed all the uprights, installed the first strain gauge in the dome, and was able to pour the concrete by Thursday. I had the crew come home for the rest of the week, because of the cold, so that the beam would have some cure time before inflation. Click the picture to see more images.
We have been making good progress in Commerce this last week. The final blocks were layed on Thursday and Javier had already started forming the 10” x 18” concrete ring beam that is going to be poured on top of the wall. We wrestled over pouring or spraying the ring beam, but then decided that one that big would probably be faster poured than sprayed. The ring beam will have 5 #6 bars in it, as well as #5 uprights into the dome every 12″. We expect the ring beam to be poured tomorrow, and inflation to happen on Thursday. You are all invited, and you can email me for more specific directions. To see all the pictures, click here.
I am posting some of the raw video from the job in Commerce, Texas. The plan is to make a video about church construction and using the block stem walls. Click read more to see the video. Read the rest of this entry »
This is a feature of a 36′ dome that was built by Monolithic in Temple, TX. This dome is unique because of its tube entryway and inset shower.
