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. 


Related Links:

• St. Joseph Catholic Church Website
• Monolithic Constructors Website
• Mike’s Picture Gallery
• Post: Strain Gauges in St. Joseph Catholic Church

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 »

Javier and I had experienced a first the other day. They brought us a load of concrete with no cement! They even did us the favor of filling the pump with it. Funnier yet is when I called them, they said instantly, “oh, we must have forgot the cement”. So my question is, how many times have they done this?

Problem: Scaffold an 88 foot dome that has only 4 36″ standard doors?

Solution: Expand our already proven Polar Scaffold to fit that size of a dome.

We started by expanding the scaffold width to 10′. This has really made the scaffold a lot sturdier. We are still using the same end frames, but different cross pieces and longer planks.

Then we redesigned the beams so that they are interchangeable pieces vs. the other expandable left and right pieces. This makes them easier to carry around, and more versatile. With the shorter universal beams, we could easily make a scaffold for any size dome from a 20′ to 100′.

One of the biggest concerns was the motor. We were concerned that the existing motor would be perfect speed for the outer edge of the scaffold, but when we are spraying in the middle it would be too slow. Also, the motor has a tendency to stop abruptly making long scaffolds hard to stand on. We purchased, with AAA Electrics help, a single phase to three phase inverter that would also double as a controller for the three phase motor. Using three phase allows us to adjust the speed of the motor. The controller does a lot of cool things for us, best of which is it lets us control the accel and decel time so that we have smooth use.

The scaffold is now complete and is going to be on the jobsite Monday. I will post more pictures as they are available.

Through the years of dome building we have always been playing a guessing game when it comes to reinforcement. So we finally found a way to find out once in for all, what is happening in these domes?

 For about a year now we have been installing strain sensors into the Monolithic Domes. We installed them into the new Faith Chapel buildings, the Mile High Church in Denver, and now we are installing them in the St. Joseph Catholic Church.

 It all starts with a little sensor that is welded to a piece of rebar. The rebar has to be grinded down so that there is a flat spot on it, then we use our fancy spot welder to weld them to the bar.

  The bars are then hung into the dome shell and the wires are run into a small plastic box. The box will contain the data gathering unit. This data unit is a wireless box that is accessible from the ground using a laptop computer with a small USB antenna. We walk into the dome, wake up the unit, take a “trigger session”, and then put the unit back to sleep. That is done once a day, and the data is emailed back to the office for organization. These trigger sessions take about a hundred samples of strain within a few seconds.

 These pictures are the two strain sensors that are going to be installed at St. Joseph next week. There will be one in the ring beam that is on top of the stem wall, and one in the bottom 4′ of the dome shell. We focus our attention on the bottom of the shell, since that is where there is the most stress.

 They are really amazing, we have a small piece of #8 rebar in my office, and you can just pull on both ends, and it will measure the strain on that huge piece of rebar.

 I have been gathering raw data for a year on other projects and with the data from this, we should have enough to come up with a real definite answer to what is going on under the concrete. These are some exciting times to be a dome builder, and of course when we have some formal results, they will be posted to Monolithic.com.Check out more of these pictures, and others on my gallery.

 

One of Monolithic’s current projects is the St. Joseph Catholic Church in Commerce, Texas. Only for the last few years have we been building domes with block stem walls, and we really like the way they look. We are about two thirds of the way done now, and we expect to be done with the rest of it by the middle of this week.

We started with a 2′ x 18” footing. Pouring the footing was like any other, but installing the uprights took more care. We had to really try hard to get the uprights spaced correctly so they would fit into the cores. Also, pouring the footing as level as possible is important, since the first courses depend on it.

We spent a long time getting the first course laid so that the rest would fly up. We hired masons to lay the block out, and our men would install the rebar and fill the cores with concrete. The first course we used just a regular 8″ x 16″ knock out block. We bought the knock out blocks because we figured on placing them upside down so that we could move the uprights into the right core. The only problem with that plan was that the masons said that it is against the code to put knock out blocks upside down, so that bombed.

Inside the cores, we put steel every 4 feet horizontal and vertical. The vertical steel was put in the cores after they we filled. Every 4′ high (six courses) we used knock out blocks to put horizontal steel. We filled the cores with our standard eight sack shotcrete mix, and pumped it with our GHP 2500. The next step, that we start this week, will be to form and either pour, or spray the top ring beam. The engineering specs have a 18″ x 10″ ring beam of concrete on top of the brick wall. And I will try to post more pictures sometime this next week.

Be sure to click on the pictures to go to the picture gallery.