Be Groovy or Leave, Concrete!

“Either be groovy or leave, man!” – Bob Dylan

The TMBV team attempts a vertical concrete panel pour

Live from Neck Down week, it’s the Thermal Mass and Buoyancy Ventilation Research Project team! From 8:00 AM to 3:00 PM last week, the 3rd-years, 5th-years, and graduates students have bonded over manual labor and project maintenance. This is the age-old tradition of Neck Down week, the start of each semester in which all year levels put their projects aside to spruce up Rural Studio’s campus and help out at ongoing and completed projects. The TMBVRP team snuck in some more concrete panel test pours in the after hours. Let’s see how they did it!

Panel Proposals

Before we dive into construction, it’s important to highlight what is different about these concrete panels. In contrast to the team’s last test pours these panels are smaller with tongue and groove edges. We will dive deeper into the tongues and grooves later. As seen above in the unfolded wall elevations above, the team experimented with different sizes and arrangements of panels. The main difference in the schemes where whether the running bond pattern stacked vertically or horizontally. The teams chose to test pour the more rectangular panels from both the vertical and horizontal running bond options.

Panel Preparations

For both chosen designs, the team planned to test making the most commonly recurring panel and the trickiest panel. Therefore, for each option the forwork for a typical rectangular panel and the more triangular panel, created by the sloping roof, was designed. However, a certain, not-Livia team member created the “construction” drawings seen above months before actual construction. The team has made significant leaps and bounds in construction drawing etiquette since. There was also much to the tongue and groove formwork that had not been fully fleshed out. So, as seen in the marked-up construction drawing above, much was decided on the fly. It was a very design-build experience.

Next, the team used their new tongue and groove router bits. Tongue and groove is a system of joining adjacent panels by means of interlocking ridges and grooves down their sides. Seen above are the first tests of the router bits to create the tongue edges for the panel formwork. For the formwork, the tongues and grooves were routed out of PVC board. PVC board will not chemically bond with the poured concrete, therefore, creating a successful cast. Connecting the concrete panels to one another using the joining system will improve their strength. The panels will act more as one structurally, but also thermally making a more effective thermal mass.

Horizontal Panel Pour

Along with testing the tongue and grooved edges, the team attempted two different pouring strategies; horizontal and vertical. Seen below is the typical, horizontal panel pour method. The team is pretty well-versed in this recipe. After pouring the panels, the team will let them cure for about a week. Onwards to the vertical pour!

Vertical Panel Pour

The vertical concrete formwork meant to create two perfect panel faces and ease panel transportation. However, you guessed it, the vertical pour was quite difficult. First, vertical formwork requires more pieces that need to fit together more precisely. You are in a sense making a very precise sandwich that leaks Mayonaise everywhere if you don’t get it right. Second, getting the masonry anchors to stay in place and attach through both large faces required a special bolting jig. Another new piece to make. Third, to keep the formwork upright required leveling and sawhorse structure. Fourth and finally, the team built a funnel to transfer the concrete through the 1-1/8″ formwork opening. And repeat for 60 plus panels!

While the smaller, triangular vertical pour went fine enough, the large rectangular panel busted open. As you can see above the triangular panel had little leakage out of the masonry anchor attachment areas. The rectangular panel however suffered catastrophic failures in this area. For now, the team awaits the curing process to see the results. However, based on these vertical tests they aren’t sure the reward will be worth the hassle. But, hey, where else in the world do you get to test pouring concrete panels vertically than in the Rural Studio graduate program? It’s always worth the hassle.

The Wood Rack

Last, but far from least, the team can’t wait to show off their new wood racks. Because the Fabrication Pavilion is their construction headquarters, the team was in charge of cleaning it up as a Neck Down week task. They are stupidly proud of these wood racks they built to take all their lumber vertical and clear space for more activities! Please admire them!

Copper has joined to say thanks for tuning in! Stop by next week to see how the panel pours and tongue and grooving worked out for the Thermal Mass and Buoyancy Ventilation Research Project Team!