Live from the Cooling Porch, it’s the Thermal Mass & Buoyancy Ventilation Research Project team! Recently, the students focused on the demonstration space beneath the Test Buildings known as the Cooling Porch. Specifically, they began constructing the retaining walls, made out of old concrete highway barriers, which allow the space to be sunken and trap all the cool air rushing out of the Test Buildings. Let’s get into it!

Mock it up!

To test the structural rigidity, building method, and pattern of the varied in size concrete blocks, the students landed on tying the blocks into the packed earth behind the wall by placing pieces of expanded metal mesh between the block courses. The blocks are dry-stacked, using only their weight and the mesh to stay in place.

connected block to earth with expanded metal mesh

The expanded metal mesh makes the wall sturdier, but also allows the students to slip the straps theyre using to move the blocks out after placement without untying the straps from the Bobcat forks.

reclaimed material palette and full coursing

The students originally planned on using concrete blocks as the benches, but they could not find enough reclaimed materials. The solution? Insert flat steel between the concrete block courses which can hold a lightweight material for sitting. The final material is still up for grabs, but for the mock-up, the team used leftover oak from the woodshop. After nailing down the building process of the retaining wall and bench, the students made sure they had each block and its future location documented. Unfortunately, to complete the design the students needed five more 4′ 3″ X 10″ x 10″ concrete blocks. Good thing they’re pros at a concrete pour!

Prep it up!

To prepare for building the retaining wall, the students dug trenches for small footings. These concrete footings will prevent the wall from settling and becoming unstable.

After pouring the footings, it was time to create formworks for the needed concrete blocks. These were constructed from extra lumber, ZIP sheathing, and rebar. The rebar, leftover from the Test Building foundations, was crafted into cages and hung from the formworks.

With all this prep going on, the research team was also fine tuning their strategy for evaluating airflow in the Test Box small-scale experiments. They are currently working on revising an article for publication which details the results of these experiments and the potential for internal thermal mass design. In particular, Cory, along with Jeff and collaborator Remy Fortin, have spent months nailing down the proper equations for the airflow taking into consideration friction. Thanks to Russian physicist, Idelchik, he finally found an equation which matches the parameters of the TMBV experiments.

Meanwhile, Rowe and Livia revisited metal working, welding angles for the steel bench supports, and cutting metal mesh.

Put it up!

At long last, the retaining commenced! Something different about the actual wall and the mock-up wall is the addition of gravel backfill and landscape fabric. The landscape fabric and gravel cover the column bracings and drain, which runs behind the wall, to prevent corrosion and blockage from the hardy Hale County clay. However, the metal mesh than has to pierce through the landscape fabric so it can be buried in the earth behind. Hot take: expanded metal mesh and landscape fabric is the worse material combination ever.

To let out some steam on a very steamy day, they brought out the concrete saw and sledge hammers. The team needed to shorten just one 8′ x 8″ x 8″ by about 2′. Cory and Jeff showed the mailability of reclaimed cementitious materials.

Three courses up and the TMBV team could not be happier with the result! The pattern and the finger joinery at the shifting walls is just what they wanted. Best of all, she’s quite sturdy. The team will keep you updated on the progress of the wall so, as always, stay tuned!

This just in: there’s is a big hole in the Thermal Mass and Buoyancy Ventilation Research Project site!

Thanks to C & T Excavation Inc. the TMBV Test Buildings have broken ground. Local and Rural Studio excavation efficiando, Tyler, completed the initial site grading and the foundation dig. Let’s take a look at how the TMBV team prepped the site for this momentous day.

Newbern’s Newest Crater

plan view drawing showing batterboard arrangement — Plan of Batter Board layout, this drawing guided students in find the foundation limits

Before you can dig a hole, you’ve got to know where to dig! This is where the superheroes of construction, batter boards, come into play. Batter boards are quintessential for starting construction so they must be precise. To clarify, batter boards are temporary frames, set beyond the corners of planned groundwork at common elevations.

student holds level on horizontal batterboard to check height — Check the level

student holds plum bob while other student marks where it hits on the ground with spray paint — Check the level

Typically, batter boards consist of two stakes driven into the ground with a horizontal member held between them. Next, once you’ve assembled and leveled the batter boards, you use construction string to “pull” layout lines. The layout lines are then secured to the batter boards. Layout lines cross the site either east to west or north to south, between batter boards, to indicate the foundation limits at their intersections. It’s important to note the elevation of the top of each batter board must match so when strings are pulled across the strings intersect.

selfie of student with their teammates rolling parking curb in background — Livia helped move the parking curbs out of the way

student kneels by batterboards with sun setting in background — Livia helped move the parking curbs out of the way

The TMBV team pulled their first layout line west to east from the Supershed columns. From this line, all other layout lines are set. When all lines’ distances and intersections’ squareness are triple-checked, the team marked the initial grading limits on the ground with spray paint. The end result, with string crisscrossing about like laser beams, feels a bit like a scene from an action movie. Especially if you practice jumping over and rolling under the strings. But, of course, none of these very professional research graduate students took part in such conduct.

student looks on as mini excavator levels site in front of super shed — pre-hole

students stand waist deep in foundation hole — pre-hole

At the end of a long day pulling strings, the team marked their initial grading and detached all the layout lines from one side. The layout lines positions are marked on the batter boards so they can be put up and down as needed. Obviously, you can’t build with a bunch of strings in your way. After the initial site grading, the students re-pulled the strings which indicated the foundation limits, marked the corners, and Tyler began digging again. In about 6 hours time, Morrisette Campus had a brand new swimming pool and the TMBV team had a real project site.

Mock-up Progression

student studies mock-up construction drawings — Rowe conquers mitering math

Student looks through small door opening in mock-up stud wall — Rowe conquers mitering math

In parallel with site groundwork, the TMBV team worked across campus on their mock-up. To mimic the SIPs walls of the test buildings, the mock-up uses 2″ x 12″ stud walls. Due to the angle of the roof and the chimneys, there was much mitering to complete and even more mitering math to figure out. The team built all the stud walls and are ready to assemble. All the especially funky parallelograms you see below are the chimney pieces. With the kit of parts complete, the team awaits columns to build upon.

small stud walls standing up under fabrication pavillion

Cooling Porch Design

True to the design-build spirit, the team is still designing as they’ve started building. The ground plane of the cooling porch was the subject of this week’s design charrette. The team has used, concrete side-walk pieces they intend on using as pavers. However, it is not decided yet how those pavers are arranged.

colorful plan view sketch of organic paver pattern in cooling patio space — Cooling Porch Sketches show what’s on the collective TMBV mind

plan and perspective view of linear paver pattern design in cooling pation — Cooling Porch Sketches show what’s on the collective TMBV mind

The team wants to eliminate any excessive cutting of the pavers, especially exact cutting, so they ruled out a linear pattern. They are pursuing a mosaic-like pattern that minimizes concrete cuts. However, without a full inventory of all the concrete pieces, it’s difficult to produce a realistic design. Therefore, in the coming weeks, the team will be taking stock of their recyclable materials. After this, they can start laying out patterns using a steer skid loader to move concrete pieces around.

Welcome to Winter

a dirt roads lead to to silos both surround by frosted grass

As mentioned in the Thermal Mass and Buoyancy Ventilation Research Project Team’s last blog post, the chill has rolled into Hale County. There is never a shortage of beautiful scenery in these parts as proven by these frosty silos. By next post the TMBV team hopes to have another gorgeous view for you; a freshly poured foundation! Here’s hoping and thanks for tuning in!

groundwork

It’s Retainin’ Men (and Livia)