Search

A worker grinds the sculpture using a platen sander (a.k.a an air-driven ten pound belt sander). After being ground with 40-grit sandpaper disks, the road grader was applied to the sculpture's surface, then the platen sander, the double action sander, and the electric buffer and rouge.

A worker grinds the surface of the sculpture using a 15 pound air-driven belt sander (sometimes referred to as a road grader). Workers wore respirators and polyethylene jumpsuits for protection while polishing the sculpture. The weatherproof tent that covered the sculpture from March to June 2004 was rebuilt in January of 2005 to protect the public from nickel chromium and hexavalent chromium particles produced during the grinding process. Although Cloud Gate was scheduled to be completed in July 2004, it was not actually finished until March 2006. Cloud Gate was officially dedicated on May 16, 2006.

A worker refines the surface of the sculpture using a double action disk sander, rubbing out the fine scratches left from the platen sander. The official dedication ceremony for Cloud Gate occurred May 16, 2006. Maggie Daley, wife of Chicago Mayor Richard M. Daley, attended the ceremony and declared that it was officially Cloud Gate Day. Anish Kapoor also attended the dedication and stated that he was "deeply touched and truly proud of the way in which 'Cloud Gate', the Bean, has entered the public consciousness."

An aerial view of the Jay Pritzker Pavilion under construction. Five months before Millennium Park opened to the public, work continues on the Pavilion. Steel and aluminum panels are still being installed though many of the finished stainless steel plates are up. Rows of stage lights can be seen along some of the ribs of the trellis closest to the stage, though none of the fixed seating is yet in place. The building immediately behind the Jay Pritzker Pavilion is the Joan W. and Irving B. Harris Theater for Music and Dance, designed to critical acclaim by Thomas Beeby. It opened in November 2003.

A view showing where the trellis connects with the headdress of the Jay Pritzker Pavilion. Taken around six weeks before Millennium Park opened to the public, this photograph shows where the trellis and the headdress come together. Lights are suspended from the bars of the trellis closest to the stage and pairs of speakers can also be seen. Between the folds of the ribbons in the headdress part of the network of catwalks is visible.

An aerial view of the Jay Pritzker Pavilion's headdress under construction. The finished stainless steel plates have been installed onto the ribbons of the headdress, or proscenium, and work continues on building the fixed seating area immediately in front of the stage. The fixed seats are below the level of the surrounding Park to help prevent ambient noise from the city seeping into the audience's area. With the curves at the eastern and western extremes of the headdress and the curve of the ribbons above the stage also helping to direct sound down and out, the sound quality of the Jay Pritzker Pavilion is superb.

Close-up view of the last plate installed onto the sculpture.

View from above of Cloud Gate during opening weekend. It was estimated that about 300,000 people visited Millennium Park during its opening weekend, July 16-18, 2004. In the years leading up to the Park's opening, the Park received media attention for being behind schedule and over budget. When it finally opened, the Park received critical accolades for its art and architecture, and enthusiastic response from the crowds that flocked to it. In particular, crowds were enchanted by the mirror like surface of Cloud Gate, touching its surface and taking photographs. Opening night included a processional by the Red Moon Theater across the BP Bridge, and an inaugural performance by the Grant Park Orchestra at the Pritzker Pavilion. This kicked off a weekend of music, performance and celebration.

Looking southwest toward Cloud Gate and SBC Plaza four days before the park was opened to the public. Crown Fountain and the Michigan Avenue street wall are visible in the background. The surface of Cloud Gate creates painterly illusions, pulling in the viewer's reflection, and giving the sculpture an interactive feel.

Looking south toward Cloud Gate. The Michigan Avenue street wall is visible in the sculpture's reflection. Formally, Kapoor's works are rooted in minimalism, but they have an enigmatic quality that creates a psychological, spiritual effect. Some of the polarities inherent in Kapoor's work include: full/empty, presence/absence, and object/void.

Looking southeast toward the Park Grill and Cloud Gate. The 110-ton sculpture sits atop a load-bearing wall which separates the Park Grill café from an underground parking garage. The lightning protection system for the sculpture goes all the way to the ground.

Looking west toward Cloud Gate. This photograph was taken less than a week before Millennium Park opened. The ongoing construction of SBC Plaza is visible in the sculpture's reflection. The sculpture was fully assembled by the end of June 2004, and was unveiled to the public the next month, although it remained incomplete until it was fully welded, ground and polished nearly two years later. The seams between the individual steel plates were still visible on the sculpture when this photograph was taken.

Workers guide the final steel plate into place on the sculpture as it is hoisted from above by a crane. Below, workers wait to adhere the plate to the sculpture from the inside.

Workers guide the final steel plate into place on the sculpture as it is hoisted from above by a crane.

Ethan Silva, president of Performance Structures, Inc. (PSI) (top left), and artist Anish Kapoor (right) look on as workers guide the final steel plate into place on the sculpture. PSI fabricated the steel plates for the sculpture based on Kapoor's design.

Steel plates on the sculpture are welded together. A tack-welding process was used prior to the Park's opening; permanent seam-welding was completed in 2005.

Artist Anish Kapoor inspects the partially completed sculpture. Prior to Cloud Gate, London-based Kapoor had completed three permanent outdoor sculptures in Canada, Japan and England.

Artist Anish Kapoor (right) inspects the partially completed sculpture. As is his practice Anish Kapoor did not name his sculpture until it was fairly well complete. The unnamed installation was affectionately known as "the Bean" by Chicagoans, much to the chagrin of Kapoor. However, at the dedication of the sculpture Kapoor acknowledged its colloquial name, his sculpture having become one of the most recognizable and popular pieces of public art in the world.

A worker climbs along the supporting steel of the partially completed sculpture while attaching steel plates. The tension of the cables and springs was adjusted constantly as construction continued to maintain the right balance.

Looking northwest toward the partially completed sculpture as a steel plate is moved into place. Each plate was covered with a protective film to maintain its polished surface before being transported from Oakland to Chicago. The protective film was removed once the final plate was in place.

View of the omphalos, a Greek word meaning "navel", from below. The omphalos was the first plate to be attached to the structural steel. Buildings visible in the background include 30 North Michigan Avenue (also known as the Michigan Boulevard Building), the Heritage at Millennium Park under construction, and the Smurfit-Stone Building.

View from below of the omphalos attached to the structural steel of the sculpture. The Aon Center is visible in the background.

Work continues on the eastern approach ramp of the BP Bridge as the subframing for the stainless steel shingles transforms the structure to look like a rollercoaster! As was the case for constructing the Jay Pritzker Pavilion, Catia software, a three-dimensional computer-aided design software originally developed to design fighter jets, was used for the construction of the BP Bridge because traditional, two-dimensional drawings were not sufficient.

Looking north toward the Jay Pritzker Pavilion as work continues on the headdress, the stage and the trellis. The trellis, which delivers the sound system to the audience on the Great Lawn, is comprised of 22 criss-crossing poles that are attached to columns around the edge of the Great Lawn. Each pole is between 12 inches and 20 inches in diameter, and as they were being installed they were held up by green scaffolding towers shown here. Once the poles were welded together and firmly anchored to the peripheral columns, the scaffolding was removed.

The stage area of the Jay Pritzker Pavilion showing construction of the steel structure for the glass stage doors. Two massive glass and steel doors were built for the stage area of the Jay Pritzker Pavilion to close off the stage between performances. Each door is 50 feet tall and 30 feet wide and they roll on special tracks in the floor and at the top of the stage.

Looking north toward the Jay Pritzker Pavilion as the steel and aluminum panels were being installed onto the headdress. In the foreground, the site of the Great Lawn is visible, as is the overhead trellis which delivers the sound to the audience below.

Looking north at the western-most edge of the Jay Pritzker Pavilion's headdress, showing steel and aluminum panels onto which the final stainless steel plates were attached. Workers used lifts to reach the structural steel as they installed the steel and aluminum panels of the headdress. The headdress is made up of 697 curved aluminum panels, with outer coverings of stainless steel. Each panel ranges in area from between 6 to 300 square feet, is about 14 inches thick, and weighs between 1,600 and 20,000 pounds.

Workers securing the steel and aluminum panels to the structural steel provide a reference to the scale of some of these pieces. The panels ranged from 6 square feet to a staggering 300 square feet.

Steel and aluminum panels are added to the underside of the headdress. The headdress, or proscenium, reaches a height of 120 feet above the stage and is an important part of the overall acoustical plan for the Pavilion. As sound is made on stage it is directed down and out toward the audience in the seated area while the curving wings east and west of the stage help direct the sound to those on the lawn.

Looking northwest toward the newly installed steel and aluminum panels on the west side of the headdress. Once these steel and aluminum panels were installed onto the yellow back up structure, the final stainless steel plates were installed onto the aluminum panels.

Looking north toward the Pavilion where the structural steel for the headdress is being installed. Many times during construction there were as many as four or five large cranes on site, plus 18 aerial lifts to hoist workers where they needed to be.

View from below of structural steel for the headdress being installed. Great skill was necessary to build the headdress: not only were there no straight lines to follow on from, but also because the builders were essentially creating abstract shapes in the sky. The progress of the Pavilion's construction was constantly checked by using surveying equipment, and by checking points against a computer model created with Catia software, a three dimensional computer-aided design software originally developed to design fighter jets.

A close-up view of part of the trellis before it was installed over the Great Lawn. Inkeeping with Frank Gehry's distinctive style, the trellis that spans the Great Lawn is not only attractive and adds to the overall aesthetic of the Jay Pritzker Pavilion, it's functional too. Charged with making sure the sound from the stage travels to the extremes of the Great Lawn, Gehry veered away from the traditional approach of speakers atop poles regularly spaced throughout the Lawn. This "forest of lollipops," as Gehry called it, detracted from the overall experience of the Lawn and interrupted sight lines to the stage and the ribbons. The solution was an airy trellis from which speakers could be suspended.

Looking west through the headdress's structural steel along Washington Street during construction. In addition to being the Pavilion's signature decorative element, the headdress, or proscenium was designed for function. Hidden within the ribbon's folds are concealed lights for the stage and catwalks to allow access for maintenance. The ribbons also shelter the closest seats to the stage from inclement weather, and they direct the sound down and out from the stage to the audience.

Looking east, the partially-built headdress is in profile as a crane lifts structural steel into place. The distance the headdress, or proscenium, extends from the stage provides a cover for most of the fixed seating area and reverberates the sound toward the audience. In the words of architect Frank Gehry, "Eighty percent of the proscenium has an acoustical function. When somebody's onstage and makes a sound, it disappears right behind your ears. You hear it, and it goes away. So anything that contains the sound or holds it in the realm of where it was made is a plus. The side panels are meant to contain sound, not let it dissipate. And the ones on top reflect the sound to the audience."

The structural steel of the sculpture (later named Cloud Gate) during a trial assembly at Performance Structures, Inc. (PSI) in Oakland, California. During the trial fit-up, the base, interior structure, and one-third of the plates were assembled.

Close-up view of the temporary rigging system used to hold the steel plates into place during assembly. The cables were removed once the sculpture was completely seam-welded. The finished sculpture is a self-supporting shell structure that expands and contracts as Chicago's weather fluctuates.

The structural steel of the sculpture towers over a lone steel plate during a trial assembly at Performance Structures, Inc. in Oakland, California.

Ethan Silva, president of Performance Structures, Inc., in front of the sculpture's structural steel in Oakland, California. The mirror-like "skin" of Cloud Gate was designed to fit loosely around the interior support system of trusses and lattice-work, allowing it to expand and contract as temperatures in Chicago fluctuate as seasons change.

A milling machine is used to remove excess material from a steel plate. In order for the steel plates forming the sculpture to fit together, the dimensions and curvature of each plate had to be exact to within one-thousandth of an inch. This level of accuracy was achieved by hand-grinding and machine-milling the plates after they had been rolled to one-hundredth of an inch accuracy, and welded to sub-frame grids. Fabrication of the 168 steel plates at Performance Structures, Inc., began in April 2002, and took over two years to complete. The largest plates were seven feet by 11 feet, and weighed up to two tons.

Steel I-beams were wrapped in rebar, or reinforcing bar, prior to their being cast in concrete. The Michigan Avenue street wall is visible in the background.

View from below of the steel I-beams forming the skeletal structure of the Pavilion's roof. In designing the stage area, Frank Gehry took great care to ensure that the sense of intimacy enjoyed by those in the fixed seating area during a performance extended to those near the back of the Great Lawn. To do this he enlarged the stage to an opening of almost 100 feet wide by 50 feet tall. To create this vast, column-free space a double row of 12 huge trusses, shown here, supported by truss girders, hold up the roof.

Looking northeast toward the construction site of the Jay Pritzker Pavilion as structural steel was erected and formwork was put in place prior to concrete being poured. Buildings along Randolph Street are visible in the background.

A steel plate beneath a precision measuring device called a Faro arm. A Faro arm is an automated scanning device that checks measurements against computer models and calculates whether they are within necessary tolerances. Once the exact dimensions were achieved, the plates were heat treated and cooled to relieve stress, and then ground and polished, and covered with protective film.