Built Expressions Bangalore :: The Park Tower

Comments (0)

Comments This Article

The Park Tower, built solely of concrete

Mona Raju, Architect

Envisaging the tower

The Park tower, addressed at 800 North Michigan Avenue in Chicago, stands skyward at an imposing height of 844 ft (257m). Before its erection, the site was previously occupied by 16-storey Park Hyatt hotel, which was built in 1960. Despite having carved a benchmark for itself amongst other skyscrapers, the tower was built without eliminating history. It utilizes the space of Perkins, Fellows & Hamilton Office and Studio, which was built in 1907. The facade of that building was retained and the tower was 40 feet away from it to give the former facade an illusion of a free standing building. The property spans across a street that prefaces the “Great Chicago Fire” of 1870. Completed in 2000, the tower bears 70 floors, out of which 67 floors are assigned for practical use. Even though the magnificent Hancock Centre stands across the Michigan Avenue, the tower is not eclipsed by its neighbour.

It has been declared the 11^th tallest building in Chicago. Considering the whole of the United States of America, it stands at

a proud 35^th spot in the list of its tallest buildings. Apart from these notable endowments, it has been announced the 83^rd tallest in the world by architectural detail. The tower dwells as a multi-utility building. It is one of the tallest buildings in the world that lack a steel frame, constructed of concrete.

Populous Honours

Distribution of Spaces

It has been designed by an illustrious Chicago-based architectural firm, Lucien Lagrange Architects. The first 20 stories of the tower are occupied by the Park Hyatt Hotel, which a five star hotel housing 203 rooms. The rest of the 47 floors are allotted to Luxury residential spaces which account to 117 of them in total. The top 8 floors occupy the entire floor, which sums up to about 8,600 square feet of area. The Park Tower was formerly intended to be constructed at 650 ft (198 meters) in height. Subsequently, the ceilings we raised to reach 12 feet, allowing the building to extend to a height of 844 ft. This increase in the ceiling heights enhanced the feel of “luxury” in the residential condominiums. The total usable area is divided into the following categories:

193,000 square feet (17,930 square meters) allotted to the Park Hyatt Hotel.
475,000 square feet (44,129 square meters) allotted to residential occupancy.
20,000 square feet (1,858 square meters) allotted to retail space.
92,000 square feet (8,547 square meters) allotted for

parking

The mechanical equipment assembled on the 68^th floor of the tower is large enough to be considered as equal to three floors in area.

The retail space includes the likes of Giorgio Armani. A small portion of this space resides in its landmark, established in 1917. The residents occupying the tower’s condominiums are allowed the advantage of access to the Park Hyatt hotel’s amenities and services.

Striking features

The fundamental elements of the external facade are vertically accented in the building’s architecture. The architect’s approach is envisaged on the building as an arrangement of recurrent courses of tinted windows positioned into warm gray spandrel (describes a space between two arches or between an arch and a rectangular enclosure) panels. The external structural columns are cladded with Buff limestone. Recessed balconies have been intentionally curved to soften the corners, where they are symmetrically placed.

Form Work

The Scaffolding and the Formwork system was custom designed by PERI and were commissioned to supply the formwork for the foundations, retaining walls, columns, walls and floor slabs of the Project. The use of the SKYDECK aluminium panel slab formwork in connection with the MULTIPROP props proved to be especially advantageous for the floor slabs. The aluminium parts of this system are very light. The heaviest component, the SLT 225 main beam, weighs only 15.4 kg. With SKYDECK the floor slabs in the core area could be quickly formed by hand – without crane support. ACS self climbing system was also adopted for the project. Functional details below;

ACS R Climbing System

SKYDECK Aluminium Slab Formwork System - With the SKYDECK drophead system, striking can be carried out after only one day (depending on the slab thickness and strength of the concrete). The drophead is released with a hammer blow which causes the formwork to drop 60 mm (panels and main beams). The panels can be separated easily from the concrete and immediately used for the next cycle. Furthermore, on-site material requirements are reduced.

The SKYDECK main beam reduces the number of props needed – only one prop is required per slab area of 3.45 m² for thicknesses up to 40 cm. This saves time and simplifies the transportation of formwork materials across the site. Systematic assembly and a high degree of safety for standard bays as well as the slab edge is achieved using SKYDECK platforms. The SLT 375 main beam provides a cantilever of approx. 1.30 m. The GS-approved SKYDECK SDB platform together with a foldable handrail frame is safely positioned by means of the SSH shuttering aid. The SKYDECK platform has a safe working load of 150 kg/m². SKYDECK panels as well as main beams are equipped with self-draining edges. The edges of the panels are undercut which ensures cleaning is kept to a minimum and thus shorter shuttering times.

SKYDECK Aluminium Panel Slab Formwork

Light props with high load-bearing capacity

MULTIPROP post shores are made of aluminium which means they are very light. For example, the MP 350 can be extended from 1.95 m to 3.50 m but weighs only 18.8 kg. The patented profile along with the actual construction of the MULTIPROP prop allows a considerably longer service life than is possible with steel tubing. MULTIPROP post shores have an integrated measuring tape which guarantees accurate prop adjustment without the need for any time-consuming measurements. Due to the continuous thread on the inner tube, each MULTIPROP prop can be used for areas with large heights.

1. Courtesy Peri Fact Sheet

Understanding the tower’s structure and finial

The Park Tower is crowned by a copper mansard roof. A Mansard or Mansard roof in architecture refers to a style of hip roof characterized by two slopes on each of its four sides with the lower slope being much steeper, almost a vertical wall, while the upper slope, usually not visible from the ground, is pitched at the minimum needed to shed water. This form makes maximum use of the interior space of the attic and is considered a practical form for adding a story to an existing building. Often the decorative potential of the Mansard is exploited through the use of convex or concave curvature and with elaborate dormer window surrounds.

It was popularized in France by the architect Francois Mansart (1598 - 1666). His treatment of high roof stories gave rise to the term "Mansard roof" (toiture A la Mansarde). Sections of the Louvre, such as the central portico of the Richelieu Wing, display this style of roof. Practically, this form of roof helps in expanding another storey to the existing building, hence allowing maximum utilization of space. This roof fulfils the purpose of being aesthetic and ornamental, apart from being functional. The tower’s identity is enhanced on an account of the contrast in the roof’s colour and form. Functionally, it is a 300-ton tuned mass damper, which refers to a structural device that reduces the horizontal movement linked with lateral wind loads. It has been noted as the first building in the United States that has been designed with the aid of a tuned mass damper from the outset. Due to its elephantine mass, the damper has inertia that prevents the building from swaying in strong winds. Another reason why this system was employed is because of the limited footprint of the building, about 28,000 square feet (2,601 square meters) in area. Although numerous other skyscrapers have employed the anti-sway system, they were introduced into the building at a later stage and not whilst construction.

Further recognition

It is one of the tallest buildings in that world that has been cladded with architectural pre-cast concrete. It also swanks of being one of the tallest towers in the world that stands on a non-steel framed structure. It is a structure that is composed exclusively of concrete frames that have been cast-in-situ.

Queer facts

- During the inauguration of the tower, one of the cheif selling points was the outlook of the stretch of the city from the hotel bathtubs.

- The pendulum, located at the top floor of the building hosting mechanics, weighs about 400 tons.

Facts Sheet