#concrete

Concrete, Concrete, and More Metal

Who said there is such a thing as, “too much concrete”? Definitely not the Horseshoe Courtyard Project team! In the last two weeks, Caleb, Claudia, and the 5th year and Graduate Student helpers poured concrete for the sidewalk extension, wall footing, and the wall mock-up. Oh, the wall? It’s made of concrete. Let’s see how they do it!

In one action-packed afternoon, the team poured the concrete sidewalk extension and the footing for the 9′ concrete entry wall. Both are located at the north end of the courtyard site. Special formwork was made to help keep the footing rebar in place. This rebar extends out of the footing and will be cast inside the wall. Special attention was also paid to the sidewalk extension by giving it a broom finish.

Mock-up # 13: The Concrete Wall

Next up, the thirteenth mock-up. This mock-up tested the finished quality of the concrete for the 9′ wall. The team experimented with how much the concrete needed to be vibrated to create a smooth surface and where to locate seams. It was also important to practice the overall process of making out-of-ground formwork and pouring into it.

Due to the dimensions of a single melamine sheet, a wood composite board with a plastic coating, no single sheet will cover the whole face of the concrete wall. Therefore a couple of options were tested using two, 2′ x 2′ panels. Each panel face tested a different option; single sheet, horizontal seam, vertical seam, and a combination of the two. Silicon sealed the joints and corners and liquid nails connected the different segments of the melamine board together. Once the concrete cured and the forms removed, the team decided horizontal seam would be best.

Only the Corner Left

After removing the formwork for the recent sidewalk extension, the last flat screen on the east side was ready for filling. Caleb, Claudia, and TMBV team members planted three more vines, weaved the rope through, and fastened the corresponding steel cables. The corner screen will be finished, once the concrete sidewalk is fully extended, to avoid trampling the plants in the process.

Spring is Upon Us

In the last couple of weeks, the courtyard has seen new colors pop up! The Carolina Jessamine or Gelsemium sempervirens, one of the two vines planted have started to bud. This week, almost all twenty of the Jessamines have bloomed or have buds that will bloom in the coming days. This beautiful vine blooms twice a year, in the fall and spring; and complements the fragrant white blooms of the Confederate Jasmine (Trachelospermum jasminoides), which will make their appearance in a few weeks!

Benches Coming Together

During Neckdown Week, the team and helpers dug and poured two of the concrete footings for the benches. And last week, the corresponding metal legs for the benches were installed. The team hammer-drilled into the concrete and epoxied the threaded rods into place. The base of the benches will be grouted to the concrete at the correct level once the third bench footing has been poured and hammer-drilled. The benches’ sitting surface consists of two eight-inch square heavy timber cypress, leftover from the Newbern Town Hall project, which will provide durability as well as comfort for the user.

Walkway Capped

Fastening cables to railing end

Finally, the end of the walkway is complete! A new quarter-inch plate was installed into the masonry wall to support the northernmost railing. The process for the installation of the plate was the same as the plates which support the walkway. The main difference being the middle two anchors that extended past the wall plate and attached to the railing aligned with the other railing frame connection point. The corner piece, while singular in its function, follows the same language and rhythm as the rest of the metal. And maintains the two-inch gap in both its connection to the last railing and to the existing ones.

Six Trees in the Ground, Seven More To Go

Dr.Dprsey and PHF fellows cleanign bricks

On a Saturday morning, the Greensboro Fellows, Dr. Dorsey, and several community members came to the courtyard site to help clean bricks! Together they cleaned about three-quarters of a pallet (roughly 350) worth of bricks. Thank you, Fellows and Dr. Dorsey, it was a great help!

Concrete Pour

Formwork pre-concrete pour

The team finished the formwork, secured the rebar mesh, and taped over the formwork spacers and screws. The slab under the walkway is divided into rectangular pavers, which follow the grid system of the rest of the courtyard, and allow two-inch gaps that correspond with screen and grate placement. This week with the help of contractor, Clyde Fields, the team poured concrete!

Cured concrete before formwork was removed

While waiting for the new trees to be delivered, we began removing the formwork! To make prying the forms out easier, longer pieces of formwork were created at the edges of each rectangular slab piece, with spacers every foot or so.

Crepe Myrtles Arrived!

Thirteen beautiful, single trunk, Natchez Crepe Myrtles arrived on site on a cloudy Thursday morning. The team unloaded all of the trees with the help of 3rd-year students, Mason, and the Bobcat. The trees have grown taller since being tagged at a nursery in northern Alabama! The caliper, or width of the tree trunk, ranges between three and four inches wide. The bottom of the tree canopy is at least six to seven feet tall, allowing people to comfortably wander beneath the canopy.

That Friday morning we, along with 3rd-years and Mason, excavated holes for the first two trees. Considering the size of the site, the trees needed to be planted two at a time before the following holes could be augured. David Hill, AU professor of landscape architecture, arrived to advise and help plant the Crepe Myrtles. The 3rd and 5th-years helped us plant the first six trees! A huge shout out to David for coming from Auburn to assist planting the first half of the new courtyard trees.

Old Bricks, New Concrete

People standing in front of screens

For a while now the team has known what materials will be used as in-fill for the screens, but it wasn’t until recently that they were able to see the rope, cable, and galvanized screen together on site! Before the new students arrived, Caleb and Claudia started testing the rope pattern. Four vertical strands were weaved through the screen perforations in a sewing-like pattern and fastened at the bottom of the first and last segment. As well as the stainless steel cables that will run every fifth perforation, in between the rope.

Concrete Curb

This semester started out with the new 5th-year students on site helping the team with formwork, batter boards, and brick rescuing! In the images above, you can see the students making the formwork to hold the concrete in place while it sets, staking it to the ground, and eventually pouring concrete in it. There are four threaded rods that were cold poured into the curb, that will function as anchors for the new pump cover.

“Construction Lines”

Strings in front of metal structures

In preparation for the site being graded again, the students set up guides to know where the edges of the brick pad will be. These strings are ten inches away from the metal screens. Consequently, creating a symmetrical edge on three sides, lining the pad up with the overall grid, and giving the vines that will be planted on the screen some buffer space.

Every Brick Counts

Students cleaning off bricks
Students salvaging and cleaning buried bricks
Stack of cleaned bricks

Before the dirt pile from the previous excavation got removed from the site, it was scoured for any useable bricks. Since the pad will be made up of reclaimed bricks, most bricks found on site are a great addition to the inventory. The students used brushes, hammers, and scrapers to remove any mortar from the bricks before starting a “clean” brick pile.

Bolted Down, Moving Up

While the concrete set, we created templates to help install the threaded rod into the footings. A laminated template ensured the holes drilled into the concrete for the threaded rods were in the correct location. The wooden template held the rods in place while the epoxy dried.

The team used the handy-dandy batter boards and plumb bob to find and mark the exact center of where the footing plates would be installed. They needed to ensure footings were spaced exactly 10 feet apart while also lining-up with the critical connection points of the walkway. Although the footing plate holes were oversized in comparison to the 5/8 inch threaded rods that attach the plates to the concrete, the rest of the screen assembly did not have as much tolerance. The tolerance at the footing plates allowed for minor adjustments as the screens were being connected and leveled to each other.

Before the holes were filled with epoxy, all of the threaded rods were marked (the depth they needed to be embedded) to ensure air bubbles in the epoxy weren’t holding the rods out of place. Nuts were threaded to support the wooden template that holds the rods in place while the epoxy dried. Once the epoxy hardened, the footing plates could be lifted into place and re-leveled in relation to other plates.