Little Island @ Pier 55
Ruttura & Sons Const. Co., Inc., West Babylon, NY
Little Island is a $250 million Hudson River Park Trust project which takes the idea of piers and parks to a new level. The most visible portion is the pots, fabricated giant cups put together with pieces called petals. 39 sets of formwork were made after extensive 3D computer modeling to create the 132 pots.
While the pots were modeled, cast, and assembled, marine contractors drove the pilings in stages, up to 200 ft. below the river. The project includes a total of 267-cylinder piles, each supporting approximately 250 to 350 tons.
The "jewel" of the project, according to Kevin Zimont, a project executive with construction management firm Hunter Roberts Construction Group, is the 700-seat amphitheater. "Architectural concrete designed for a 100-year life cycle made it difficult to satisfy the architect's wishes," says D. Thomas Ruttura, Ruttura and Sons Const. Co., Inc.
Superior Gunite, Jersey City, NJ
Using shotcrete to complete the eight web fins on the I-91 Brattleboro Bridge piers solved the project’s unforeseen snag. The installers had been placing sculpted-rock form panels on the piers. However they couldn’t place the forms at the arched and inverted sections near the top.
Working and carving overhead at 120 feet presented a big challenge. The only access was pumping upward from below the bridge. Shotcrete allowed the installers to place the concrete on the fins, as well as seamlessly match the already-placed precast panels..
Using shotcrete, the contractor not only avoided delays, but also gained time on the schedule. Superior Gunite completed the shotcrete segment in only nine days. The owner said the sculpted shotcrete looked better than the precast panels.
Sawmill Lakes Recreation Center Splashpad
Bullion Coatings, Katy, TX
This splashpad features Sundek products in an array of colors and patterns. It was designed to mimic the swamps of Louisiana with stars reflected in the water. The design consists of fourteen custom colors, 400 stars, six “constellations,” three template trees, four colors on the “grass” area, and a four-color template moon.
Working with the general contractor, Bullion was on a tight timeline. They were set to start the project the week after Hurricane Harvey hit Houston, and although Houston experienced the worst natural disaster in its history, work had to continue. Crews arrived to three inches of mud on the site with 15 days to finish. It took six days to lay-out and texture the exact design from the architectural plans. The remaining nine days were spent meticulously applying the 14 custom colors. Throughout the 15 days of install they had three days of rain. The project was completed on time and to architectural specifications.
Atlanta Botanical Garden
T.B. Penick & Sons, Inc.
The gardens in Storza Woods comprise a richly detailed strolling path set in a four-acre mature woodland. A combination of elevated walkways and structural slabs on helical piles were installed to minimize soil disturbance around the many magnificent hardwood trees.
The mosaic patterns were based on plant morphology. LithoMosaic(tm) is an innovative approach to mosaics and is the only known system on the market that installs mosaics in a full thickness monolithic pour, allowing artists and architects to design vast mosaics no longer limited by scale.
Its durability allows it to be installed in any climate unlike traditional mosaics that are vulnerable to freeze-thaw cycles allowing it also to be used in either flatwork or vertical applications to create stunning masterpieces with unrivaled longevity.
Mission Concepcion Park
Sundek of San Antonio, San Antonio, TX
Also known as River Return, environmental artist Stacy Levy created the walkway design that mimics the swirls and eddies of the San Antonio River. River return is the northernmost in the Mission Reach and likely the first to be encountered by visitors, the Mission Concepción portal tells the story of the establishment of the five Spanish Missions and announces one's arrival at Mission Concepción from the San Antonio River.
The concrete was first stained, followed by months of contractors using a needle scaler to remove the surface. What was left was a beautiful combination of stained and exposed concrete. San Antonio’s mayor commented “The San Antonio River flows through the city, its liquid presence flowing past the hardscape of the urban environment. This wonderful contrast of liquid nature and solid infrastructure is stunning.” San Antonio River Authority manager Suzanne Scott stated “With our recently recognized World Heritage designation, it is even more important to celebrate the connections between the river… to the wonderful Mission at this location.”
USF Polytechnic 555 Building
Baker Concrete Construction, Ft. Lauderdale Office
Some call this building a modern architectural marvel. ENR Magazine awarded it Global Project of the Year for 2015. The innovative design in architectural concrete, by Santiago Calatrava and Festina Lente, includes an elliptical-shaped structure highlighted with exposed concrete raker portals. Due to the challenges of the elliptical shape, the entrance ends were initially left off to allow for construction access to the building's main area.
The first architectural concrete constructed were the retaining walls, with integral concrete seating caps. These walls defined the building's perimeter from the reflection ponds. The architectural site seat walls not only separate the building from the adjacent reflection ponds, but also separate the reflection ponds across the entire site where together they total a mile in length.
The main building's architectural concrete began with 142 column portals spaced at eight feet on center in a curving layout, framing the endless hallway and supporting the second story of the building’s perimeter. The shape of these portals required triangular bracing between two columns, using self-consolidating concrete to monolithically pour. After column construction, the second-level elevated beams and slabs were completed and followed by the polished concrete ground floor slabs.
The two main entrances began with perimeter architectural concrete columns connecting to each of the 16 unique raker portals. These portals support the roof and tie into an oval concrete skylight that illuminates the grand entry polished concrete stairs. Outside of the architectural concrete challenges, the owner required local vendors to be used. With the high standards required for this building, the GC paired the smaller local vendors with larger vendors to monitor the work and ensure a quality product.
Doral Park Pavilion
Douglas Wood Associates, Coral Gables, FL
On the outskirts of Miami, this piece, was designed by internationally-renowned artist Michelle Oka Doner, who envisioned the structure as a “feral” gateway to the adjacent Everglades. The structure is reinforced concrete, strengthened by structural steel spines. A self-compacting mix with a 24-inch spread was chosen to assure complete filling of the intricate forms. Flyash replaced 40% of the cementitious material and a 56-day design strength was specified. The completed pavilion spans 50 feet and extends to a height of 25-feet.
Found objects in nature were digitally scanned in 3D. In collaboration with the engineer and contractor, electronic models were manipulated by the artist and landscape architect to create conceptual designs. Scale models were created using 3D printers. The team determined that the large, intricately shaped object could best be constructed in cast concrete, using forms of expanded polystyrene, sculpted by robotic routers, guided by the 3D computer model. The engineer used the same model for the conceptual structural design, which was then analyzed using sophisticated finite-element software. The structure is reinforced concrete, strengthened by structural steel spines. Within the 3D model, the engineer kinked, bent and skewed the spines to fit the object. The spines were reinforced and stiffened to withstand hurricane winds. For durability, reinforcing bars and spines were hot-dipped galvanized.
Turowski Pool Deck
Tom Ralston Concrete, Santa Cruz, CA
This job was one year in the making and used 197 cy of concrete. The site, with its limited access and steep terrain, provided a major challenge. Ralston had to build both structural and decorative walls and find a way to build a pool within the walls. The spoils of the structural work were exported up hill, while much of the engineered fill had to be moved down the hillside. The final design was a collaboration between owner, architect and Tom Ralston Concrete. The stair lights, fire bowl rings and fire pit rings were all custom designed by Ralston.
San Diego New Central Library
Morley Construction Company, Santa Monica, CA
The structure employs an architectural cast-in-place concrete Special Moment Resisting Frame (SMRF). SMRF columns and beams resist shear forces within the structure (eliminating the need for shear walls) and are joined with 2-way joist & beam conventionally reinforced "waffle" slab floor plates. Typical SMRF columns are 30 in x 75 in, 48 in x 75 in, and 75 in x 75 in, but can be as large as 88 in x 75 in. In total, the building utilizes over 43,000 cubic yards of structural and architectural concrete.
Challenges included mass concreting, unprecedented architectural concrete aesthetic program requirements, one-of-a-kind components such as the Gravity Arch supported main lobby & custom roof structures supporting the Reading Room Roof and Special Events Roof.
All concrete above grade is designated to be fair-faced, as-cast utilizing Type Ill CPC Colton/Mojave architectural cement. Through discussions with Architect Rob Quigley, FAIA, Morley determined the priorities for architectural concrete to maintain consistency of color without mottling, paste loss, or "coffee stains" - [color trumps all] to be free of sheen - all concrete should have a flat/matte finish, gloss is undesirable
Plywood is to be sized to human scale with no sheets larger than 4x4 or 3x6 and oriented randomly to create a "quilted" or "collage" effect. Plywood should vary in size proportional to the application (i.e.: a column can use a different layout than the walls and should column face to column face so that no two sides are alike to provide minimal read of plywood grain, "footballs", and other surface imperfections. While smooth architectural plywood is to be used, variations of planar surfaces and slight gaps in plywood butting were desirable. Re-sheeting forms should be avoided with the face sheeting degrading only slightly over many reuses. Slight weathering of the forms is acceptable, even desirable.
Tom Ralston Concrete, Santa Cruz, CA
The first challenge of this project was to retain the hillside while working with an existing waterline that could not be moved. Access was limited, forcing Ralston to use small bobcats to load every bucket of dirt. All hillside excavation was done by hand, which took three weeks. The project required 450 yards of concrete, and 200 yards of dirt were hauled away. The judges called this a ͞stunning͟ project; amazing, astounding, and extremely demanding. They were particularly impressed with the excavation required, the lighting in the walls and the appearance of the hardscape both in the daytime and at night.
Cutting Edge Decorative Concrete, Richfield, Ohio
This amazing project started with no actual plan and evolved on the whims of a very eccentric client. When the owner saw what could be accomplished with concrete, this residence became a two-year project which included a pool deck and fire pit, a two-story bedroom addition, a helicopter pad, a catwalk leading to a concrete patio over an outdoor kitchen, a courtyard with fire table, a pump house with fireplace, cabana, concrete walls and more.
Fillmore Center Plaza
Bay Area Concretes, Inc., Livermore, California
17,000 SF of architectural concrete and new hardscape. Bay Area Concretes used an exotic aggregate surface finishing technique on 12’ walls, radius seatwalls, and a fountain. Texture skins and color hardener were used in the perimeter paving areas that surround the main plaza.
Progressive Concrete Works, Phoenix, Arizona
This project utilized over 90,000 SF of multiple stamped concrete colors and patterns intended to lend a sophisticated atmosphere to the community. One of the challenges was the arrangement of the patterns in respect to each other and the buildings, leading to difficult cuts and pattern applications. A second challenge was that it was installed during the four hottest months of the year, with temperatures reaching over 110°.