Designed - MIT Architecture · It was 1999 and Steven Holl, the founder of New York City–based Steven Holl Architects (sha), was working with Guy Nordenson and Associates Structural

he bold design of the Henry W. and Marion H. Bloch Gallery of Art—a 165,000 sq ft (15,000 m²) addition that has increased

the floor space of the Nelson-At-kins Museum of Art, in Kansas City, Missouri, by 71 percent—be-gan with an equally bold move by the design team to break the rules of the project’s design competition. It was 1999 and Steven Holl, the founder of New York City–based

Steven Holl Architects (sha), was working with Guy Nordenson and Associates Structural Engineers, L.L.P., also based in New York City, on the proposed Bloch Building, named in honor of the chairman of the museum’s board

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Caption Caption Caption Caption Caption Caption a more common

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Designed To a T

T

A series of innovative T-shaped supports underscores

the structural and architectural design of a 165,000 sq ft

(15,000 m²) addition to the Nelson-Atkins Museum of

Art, in Kansas City, Missouri, as well as of an adjoining

underground parking garage that is topped by a skylight-

pierced reflecting pool. Although the addition also is located mostly underground, it is

distinguished by five translucent glazed structures that rise above grade to channel natural light

into the lobby and key gallery spaces below.

By RobeRt Reid

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The Henry W. and Marion H. Bloch Gallery of Art adds

165,000 sq ft (15,000 m²) to the neoclassical Nelson-Atkins Museum of Art, in Kansas City, Missouri. Of the addition’s five aboveground structures, called lenses, the largest features a

wide-span transparent entrance. Round skylights in the adjoining reflecting pool are illuminated by the lights of the parking garage

located beneath the pool.

© 2009 American Society of Civil Engineers © 2009 American Society of Civil Engineers

of directors and his wife. Henry W. Bloch is a cofounder of the accounting firm h&r Block, which is based in Kansas City, Missouri. (The spelling of the family name was altered in the firm’s name for ease of pronunciation.)

Five other architects also were vying to design the addi-tion, which was needed to house the museum’s collection of modern and African art. The competition brief specified that the best site for the new building would be on the north side of the Nelson-Atkins’s 22 acre (9 ha) campus behind the lime-stone facade of the original museum building. That six-story, 234,000 sq ft (21,700 m²) neoclassical structure—dubbed a temple of art—opened to the public in December 1933.

Most of the architecture and engineering teams in the competition presented designs that would be constructed in that northern space. They were large structures that would use the existing building as a backdrop and rise above a planned parking garage in the same area. But the winning design team “broke the competition guidelines and took a risk,” proposing a slender, elongated structure—840 ft (256 m) long and ranging in width from approximately 60 ft (18.3 m) at its northern end to a maximum of 150 ft (45.7 m) at the southernmost point—that would cas-cade down the gently sloping hill along the eastern edge

of the museum property, explains Guy Nordenson, p.e., s.e., f.asce, the founder of Guy Nordenson and Associates, who has worked with Holl on numerous projects since the 1980s.

Breaking the rules proved to be a risk worth taking, for the Nelson-Atkins competition judges selected the sha design as “a magical response to the landscape and to the original building,” according to the pages at the museum’s Web site dealing with the project. Construction of the Bloch Building began in April 2001 and was completed by October 2006. Opened officially in June 2007, the new structure and its ad-joining parking garage have also proved to be critical success-es, garnering numerous awards and honors, including the top spot on Time magazine’s December 2007 list of the 10 best (new and upcoming) architectural achievements.

Although the Bloch Building is largely buried in the hill-side, it features a series of freestanding glazed structures that rise above a vegetated roof. Referred to as lenses, these undu-lating and irregularly shaped components stand in marked

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contrast to the strictly rectangular form of the museum’s original Beaux-Arts struc-ture. But the design is very much in keep-ing with the surrounding landscape, Nor-denson explains, and on its western side the addition with its “green” roof com-plements and opens onto the museum’s Kansas City Sculpture Park. This large green space features more than 30 outdoor art objects, including one of the Nelson-Atkins’s signature acquisitions: a giant badminton shuttlecock designed by Claes Oldenburg and Coosje van Bruggen.

The sha design also placed the new parking garage underground. Thus this two-story facility, to the north of the orig-

inal building, creates an entrance plaza for buses and other vehicles accessing the addition. The plaza surrounds a large but shallow reflecting pool with a monumen-tal installation by Walter De Maria that features a rectangular “sun” of gold leaf surrounded by 34 round “moon” sky-lights that channel natural light to the upper level of the garage.

Compared with the visually heavy bulk of the museum’s original building, the steel and glass addition gives the im-pression of a light structure; indeed, the design’s guiding metaphor invoked a feather versus a stone, notes Nordenson. Moreover, each lens is clad in a series of

j u n e 2 0 0 9 C i v i l E n g i n e e r i n g [43]

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Bloch Building Site Plan

Located mostly underground, the slen-der, elongated Bloch Building, left, cas-cades down the gently sloping hill on the eastern edge of the museum prop-

erty; the five lenses rise above grade to channel natural light into the lobby and key gallery spaces below. By placing a two-story parking garage underground to the north of the original building, the

designers created an entrance plaza for buses and other vehicles. The plaza surrounds a large but shallow reflect-ing pool with a monumental installa-tion by Walter De Maria that features a rectangular “sun” of gold leaf sur-

rounded by 34 “moon” skylights.

1 Entry plaza 2 Reflecting pool 3 Lens 1/lobby 4 Lens 2

5 Lens 3 6 Lens 4 7 Lens 5 8 Original museum

9 Sculpture park lawn 10 Garage below 11 Garage entrance

0 ft 100 ft 300 ft 600 ft

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The Nelson-Atkins competition judges selected the sha design as “a magical response to the landscape and to the original building.”


translucent glazed panels that softly illumi-nate the gallery spaces below during the day-time and are artificially illuminated from within at night to create something suggest-ing a Japanese lantern, adds Kelley Gipple, p.e., a principal of Structural Engineering Associates, Inc., of Kansas City, Missouri, the firm that served as the associate structural engineer on the project.

Located directly alongside the original museum, the Bloch Building is so close to its neighbor that the southernmost portion of the first lens, which serves as the Bloch’s entrance and lobby and is the largest of the aboveground structures, must angle away to avoid overlapping some of the neoclas-sical columns of the original facade. Below grade, the two structures are connected by new passages that access a large elevator. The passages and elevator were created to move both visitors and artwork between the two buildings. A large, an-gled skylight juts up from the green space that separates the new and old facades, bringing natural light into the lower lobby of the first lens.

The hillside in which the Bloch Building was construct-ed declines approximately 22 ft (6.7 m) in elevation from the first lens to the fifth and is restrained along its eastern edge by a series of tall retaining walls of reinforced concrete; the hillside is also retained by a preexisting line of shorter stone walls that separate the bottom of the slope from the adjoin-ing Rockhill Road, notes Gipple. The new concrete retaining walls range in thickness from approximately 12 in. (305 mm) to 30 in. (762 mm) and feature a textured surface that com-plements the stone walls and imparts aesthetic appeal for the benefit of the largely residential neighborhood, southeast of downtown Kansas City, in which the museum campus is located. The berm of the hillside and the retaining walls also give the building a less imposing appearance; from end to end it is equivalent to a 67-story building lying on its side, notes Nordenson.

Each lens is irregular in shape and follows a unique align-ment, but in general the first lens is sited in a north–south direction along the edge of the original museum while the four other lenses are aligned in an east–west direction and cut

across the underground portions of the addi-tion, extending outward from the structure’s western side, which fronts the sculpture gar-den. The exact dimensions of each lens are difficult to measure, notes Gipple. For ex-ample, the first lens rises approximately 40 ft

(12.2 m) above grade and stretches approximately 235 ft (72 m) in length but just 34 to 60 ft (10.4 to 18.3 m) in width, while the third lens measures approximately 90 ft (27.4 m) in the east–west direction, approximately 32 ft (9.7 m) in the north–south direction, and approximately 9 ft (2.7 m) above grade.

The first lens features a double-height lobby and an upper level that houses a library and office space; a long ramp leads visitors down to the lower lobby level and ends just be-neath the angled skylight.

The second

lens is the only oth-er lens to feature an up-

per level, which houses a din-ing room. The aboveground portions

of the three other lenses serve only as glazed openings to diffuse natural light into the galler-

ies below.The basic framing of the Bloch Building can be com-

pared to a sophisticated lean-to, notes Nordenson, because the eastern side of the building rests against the hillside and the retaining walls while the western side is largely support-ed on steel I-beam columns, steel framing and concrete slabs on metal decks forming the interstitial structure. The steel framing for the lenses and the underground portions of the


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Each of the addition’s five lens-es is clad in a series of translu-cent glazed panels that are illu-minated from within at night to

suggest a Japanese lantern.

structure typically consists of W 18 to W 24 members weighing less than 80 lb/ft (119 kg/m), although there are also some heftier elements, including W 27 × 235 beams that support a transparent glazed opening between the third and fourth lenses. There is even a W 36 × 359 girder with cover plates that spans a 64 ft (19.5 m) long transparent glazed wall between the fourth and fifth lenses and creates the en-trance for a gallery known as the Noguchi Court, a space that houses sculptures created by Isamu Noguchi, notes Gipple.

The lens portions of the Bloch Build-ing also required additional innovative framing to accommodate the special requirements of these struc-tures. The second, third, and fourth lenses, for instance, feature a system of

nominally T-shaped supports

that fulfill both structur-al and architectural purposes. Al-

though called Ts, some of the supports actually re-

semble a Y or other shapes.The structural Ts consist of a

series of vertical trusses that be-gin in the service level basement in

the second, third, and fourth lenses and ex-tend up to support the lens roofs. Measuring more than 50 ft (15.2 m) tall, depending on location, the structural Ts are arrayed in rows

in the east–west direction of the lenses and are spaced at ap-proximately 10 to 15 ft (3 to 4.6 m) intervals “like a march-ing plane of structures,” explains Nordenson. At the base-

ment level, the structural Ts are open, but in the gallery spaces and

in the above-

ground lenses these truss-es are encased in walls of gypsum board and plaster

for aesthetic purposes. Art is hung on the walls of some of the

structural Ts, and entrances have been cut be-tween the trusses in some cases. Although the

structural T walls are generally located away from the perimeter walls of the gallery spaces so that visi-tors can walk around them, the upper branches of

some of the Ts are, much like the stays of a sailboat’s mast, tied to the thin steel tubes or rods within the glazed walls, notes Nordenson.

The structural Ts are also referred to as breathing Ts be-cause the hollow interior spaces between the trusses are used to enclose the ductwork for the building’s heating and venti-lation system and other services, says Nordenson.

In addition to the structural Ts, the interi-ors of the lens gallery spaces feature a series of smaller steel-framed, plaster-enclosed struc-tures called fluttering Ts that help to define the varying curves and shapes of the gallery ceilings, says Gipple. The ceilings at certain locations can appear to be “almost like a wing fluttering over your head . . . which creates a whole play of shadows” from the light that is diffused into the space by the lens, explains


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The addition opens onto the Kansas City Sculpture Park, which features more than 30 outdoor art objects, includ-

ing one of the Nelson-Atkins’s signature acquisitions: a gi-ant badminton shuttlecock

designed by Claes Oldenburg and Coosje van Bruggen.

Each lens is irregular in shape and follows a unique alignment.

three-dimenSional

View of Bloch Building

Structural SyStem

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Nordenson. Although some of the fluttering Ts are tied into the structural Ts, most of them are used primarily to define the irregular ceiling geometries.

The first lens includes neither breathing nor fluttering T supports, but its two-story lobby does feature a “fairly dra-matic” staircase that spans a distance of approximately 60 ft (18.3 m) to access an upper-level office and library space, notes Nordenson. The stairs are at the western side of the building at the transparent glass wall that forms the entrance to the first lens. They are supported on just one side—the side farthest from the glass—by a fabricated steel box beam that also serves as a railing; the beam measures approximately 8 in. (203 mm) wide by approximately 3.5 ft (1.1 m) tall in cross section. The steps cantilever approximately 6 ft (1.8 m) from this beam. Although there is a second railing on the glass-wall side that is attached to the vertical aluminum mullions, “you feel you’re in the open,” notes Gipple, because “structurally, there is a small gap between the edge of the step and the glass wall.”

The roof of the first lens is supported by a steel truss that is approximately 131 ft (40 m) long and 15 ft (4.6 m) deep and is aligned diagonally across the top of the structure to act as a central spine, notes Gipple. This massive spine truss is sup-ported in the center of the lobby by a vertical truss pier; both the pier and the spine truss are covered in white plaster to complement the surrounding palette, Nordenson adds. The top and bottom chords of the spine truss feature W 24 × 250 and W 24 × 192 steel members with W 14 × 90 diagonals in most cases and W 14 × 193 elements in key locations.

Steel beams ranging in size from W 21 × 166 to W 14 × 34 cantilever 6 to 26 ft (1.8 to 7.9 m) from the spine truss, depending on their location. The cantilevering beams con-nect to steel pipe sections 4 in. (102 mm) in diameter that either extend to the ground or, on the western side of the first lens, act as hangers to support the frosted glazed panels that are suspended above the wide-span transparent entrance to the first lens.

The 70,000 sq ft (6,500 m²) of frosted glazing through-out the various lenses includes an exterior double layer of in-terlocking structural glass planks, each approximately 16 in.

(406 mm) wide and 10 to 18 ft (3 to 5.5 m) tall. To form the double layer, the planks are separated by a translucent insula-tion. There is also an interior single layer of glazed panels of a translucent, laminated glass of low iron content with an acid-etched finish. Although the design had originally envisioned vertical spans of as much as 22 ft (6.7) for the glazed panels, the height of the glass had to be reduced by 4 ft (1.2 m) when deflection calculations indicated the potential for excessive movement in certain locations, notes Gipple.

In addition to the cantilevered roof system in the first lens, the glazed walls in the lenses are supported via foundation walls, elevated floor framing, elevated catwalk framing, and other methods.

The catwalk system, in particular, serves a dual purpose. Measuring approximately 2.5 ft (0.8 m) wide, the catwalks act as horizontal trusses to support the glazing both lateral-ly and vertically. A track along the outer edges supports the bottom of one set of glazed panels while a header mullion grips the tops of another set of panels, explains Gipple. The catwalks also provide access for cleaning and maintaining the panels from within a pressurized air cavity that is climate controlled to prevent condensation from forming on the in-terior walls. Moisture, notes Gipple, could damage the mu-seum’s artwork.

The catwalks in each lens are visible on the white glazed facades as slender horizontal lines that separate upper and lower sections of glazed panels.

At the entrance to the first lens, the potential weight of the glass panels and catwalk that would be suspended from the cantilevered roof structure created a considerable challenge during construction. This was because the soffit at the bottom of the frosted panels had to remain level to accommodate the entrance’s glass wall even while the glass panels were being in-stalled and their shifting weight was causing the cantilever to deflect by varying amounts, explains Gipple. Working close-ly together, the design team and the contractor—the Kansas City, Missouri, office of J.E. Dunn Construction Company—met this challenge by using a series of 55 gal (208 L) drums of water to preload the cantilevered beams with the equivalent

weight of the frosted glass. As each panel ©

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of glass was installed, sufficient water was bled off from the drums to control the deflection and keep the soffit level until all the glazing was successfully in place, Gipple notes.

A somewhat similar preloading system was used in installing the glazed panels that face the vegetated roof portions of the Bloch Building. As Gipple explains, “We expected [the contractor] to just put the [soil] on and then construct the lenses and install the glaz-ing, but that wasn’t an easily constructable so-lution.” If it rained before the glazing was in place, the soil would turn to mud and could flow into the open wall of the lens, potentially damaging the interior space. At the same time, the contractor had to take into account the deflections that the weight of the soil would

produce on the roof adjoining the wall of the lens that was soon to be glazed.

To solve this problem, the contractor and the design team placed large concrete traffic barri-ers on the roof portion beside the open lens to represent the weight of the soil. The contractor could then install the glazing in the lens with the roof already deflected. As the soil was added, an equivalent weight of concrete barrier could be removed “and the glazing support elevation would remain unchanged,” Gipple says.

Because the vegetated roof portions are designed to accommodate visitors—there are even pathways and works of art on the green space between some of the lenses—the roof

structures in those sections were designed to support approx-imately 200 psf (977 kg/m²) of superimposed load, twice the design loads for other portions of the roof, notes Gipple.

The underground portions of the Bloch Building cascade down the campus hillside in three main stepped sections: the

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elongitudinal Section of the Bloch Building

The hillside in which the Bloch Building was constructed de-

clines approximately 22 ft (6.7 m) in elevation from the first to the fifth lens. It is re-

strained along its eastern edge by a series of tall, reinforced-concrete retaining walls as

well as by a preexisting line of shorter stone walls that sepa-

rate the bottom of the slope from the adjoining road.

At the entrance to the first lens, the potential weight of the glass panels and catwalk that would be suspended from the cantilevered roof structure created a considerable challenge during construction.

1 Upper lobby

2 Lower lobby

3 Contemporary art

4 Photography

5 Featured exhibitions

6 Art service level

7 Multipurpose room

8 Café


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1 Upper lobby

2 Lower lobby

3 Contemporary art

4 Photography

5 Featured exhibitions

6 Art service level

7 Multipurpose room

8 Café


first, or topmost, section includes the upper and lower lobby spaces, as well as a café; the second includes the second lens and gallery spaces for contemporary art; and the third includes not just the third, fourth, and fifth lenses but also galleries for African art, photography, and special exhibits, as well as the Noguchi Court. Sloping ramps and stairs enable visitors to move between the various levels of galleries.

A basement art service level also connects key portions of each stepped section, and an elevator in the fifth lens fa-cilitates the movement of art objects from the basement loading dock to the gallery spaces.

The sites for the first lens and the parking garage were excavated through an overburden of clay to a depth of ap-proximately 35 ft (10.7 m) from the existing grade. The structures bear on either shale or limestone, says Gipple. The cuts for the rest of the Bloch Building extended down approximately 25 to 30 ft (7.7 to 9.1 m), depending on the elevation of the stepped sections, and also bear on shale or limestone, notes Gipple.

The foundations of the Bloch Building include contin-uous footings under the perimeter walls, a range of spread footings in the interior portions, and piers in one key loca-tion, Gipple says. The basement perimeter walls are nomi-nally 1 ft (0.3 m) thick and are centered on continuous con-crete footings approximately 3 ft (0.9 m) wide. Most of the interior footings measure 4 to 5 ft (1.2 to 1.5 m) square, al-though some are as large as 6 ft (1.8 m) square and even 12 by 6 ft (3.7 by 1.8 m), he notes.

Near the fifth lens, the Noguchi Court features several heavy stone art objects that are located above an area of new-ly compacted fill rather than a basement. Thus, that space is founded on a series of concrete piers that for the most part are 3 ft (0.9 m) in diameter and range in depth from 15 ft (4.6 m) to 20 ft (6.1 m).

Because the museum staff was concerned about possible damage to the artwork in the original building during the ex-cavations for the Bloch foundations—work that in some plac-es was conducted quite close to the foundations of the origi-nal building—Terracon, a consulting engineering firm based in Olathe, Kansas, carefully monitored the vibrations. Some gallery spaces in the original building were temporarily closed during the construction of the Bloch Building, Gipple notes, especially the spaces directly above a new tunnel, an elevator, and a visitor passage that were constructed to link the Bloch Building to the original museum structure.

The new entrance that connects the two buildings “pro-vided an engineering challenge equal to any other on the project,” says Gipple. The service tunnel and the large el-evator, which is more than 19 by 16 ft (5.8 by 4.9 m), were constructed nearly 40 ft (12.2 m) beneath the lowest floor of the original building and nearly 25 ft (7.6 m) below that structure’s concrete foundation piers. During the excavation of the elevator pit, these piers had to be supported on tem-porary steel beams via hydraulic jacks to take the 300,000 lb (136,000 kg) load of the original building’s limestone and brick wall. Concrete columns were cast beneath the existing piers to extend their depth, and then, in what was the most critical moment in the operation, the


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Caption Caption Caption Caption Caption Caption a more common

practice. The engineers used this study to increase their un-

derstanding of different applica-tions, types, and brands. After

learning more about such char-acteristics as efflorescence,

consistency, and color match-ing, they explored the availabil-

Sloping ramps and stairs enable visitors

to move between the various levels

of galleries.

(Continued on Page 72)

The second, third, and fourth lenses are supported

on a series of vertical trusses called structural Ts that begin in the service level basements and extend upward to support the lens roofs. The interiors of the lens gallery spaces feature smaller steel-framed, plaster-

enclosed structures called fluttering Ts that help to define

the irregular geometries of the gallery ceilings.

The second, third, and fourth lenses are supported

on a series of vertical trusses called structural Ts that begin in the service level basements and extend upward to support the lens roofs. The interiors of the lens gallery spaces feature smaller steel-framed, plaster-

enclosed structures called fluttering Ts that help to define

the irregular geometries of the gallery ceilings.

The two-story lobby of Lens 1 features a staircase that spans a distance of approximately 60 ft (18.3 m) to access an upper-level office and library space. The cantilevered stairs are supported on just one side by a fabricated steel box beam that also serves as a

railing. The roof of the first lens is supported by a steel truss, below, approximately 131 ft (40 m) long and 15 ft (4.6 m) deep and is aligned

diagonally across the top of the structure to act as a central spine.


piers were cut free from the steel beams.

“At the time you cut the pier loose it would either try to spring up or sag,” Gipple explains. “If you calculate it per-fectly to estimate the loads, it won’t do either, but it’s a challenge. You can’t just jack in extra load, because then the building would move up and crack the stone. Or if you underestimated the load it would sag and crack the stone.”

As it turned out, “our measurement of movement was minuscule and we didn’t encounter even one crack in the east stone wall,” Gipple adds. “I was in the hole with the contractor when they saw-cut the piers and transferred the load to the steel beams. It was re-warding to see the solution come off without an issue.”

A passage for museum visitors was also constructed atop the service tun-nel to link the new building to a pre-existing entrance on the eastern side of the original structure.

Because the new underground park-ing garage was intended to have an aes-thetic as well as a utilitarian purpose—Holl envisioned it as the first part of a visitor’s museum experience—the de-sign team incorporated a large ramp that leads directly from the upper level of the garage straight into the museum lobby. “You get the feeling that you just park the car and walk toward the mu-seum, and you’re walking right into it, not walking into a basement lobby and then having to climb stairs to reach the actual museum,” says Nordenson. Thus, he adds, “the people who are entering at the ground level [at the entrance of the first lens] will enter, in effect, the same space as the people entering from the underground garage.”

The team also did not want to use a traditional support system for the garage roof and floors. Instead, they developed a new form of precast-con-crete support called a wave T, a prefab-ricated beam of prestressed concrete that features a wavelike curve on the bottom. Each wave T is 12 ft (3.7 m) wide and spans 60 ft (18.3 m). In plan, the garage is 240 by 328 ft (73 by 100 m). In contrast to a more traditional


Des igned to a T

(Continued from Page 48)

double T beam, which relies on two ver-tical legs, the wave T is supported at only one narrow point by a single col-umn; these columns are spaced at 12 ft (3.7 m) intervals, notes Gipple. Stainless steel bent plates embedded in the flang-es of the wave Ts at 8 ft (2.4 m) intervals are welded together to connect adjacent supports.

The upper level of the structure fea-tures a series of porthole skylights, each approximately 3 ft (0.9 m) in diame-ter, that help create the reflecting pool sculpture that sits atop a portion of the garage roof. Some of the openings for these skylights were cast directly in the concrete of the wave Ts, Gipple notes.

Together, the wavy beams, the col-onnade, and the glazed portholes “cre-ate this kind of corrugated ceiling pat-tern...so there’s light coming down through the water and through those skylights in between the wave Ts,” ex-plains Nordenson.

The new garage features two sizes of wave Ts. The upper-level version is heavi-er to accommodate the greater loads it must bear. The floor-to-floor height of the upper level is approximately 19 ft (5.8 m), versus 11 ft (3.3 m) for the low-er level. The upper-level wave Ts, which support the driving plaza, the reflecting pool, and a large portion of the vegetat-ed roof, weigh approximately 92,000 lb (41,700 kg), compared with 86,000 lb (39,000 kg) for the lower-level supports. To reduce the weight as much as possi-ble, both versions were constructed with lightweight concrete and feature cen-ter voids. The lower-level wave Ts have a single void roughly 27 in. (656 mm) in diameter, while the upper-level sup-ports have twin voids, each nearly 17 in. (432 mm) in diameter, notes Gipple.

The reflecting pool atop the garage measures 134 by 161 ft (41 by 49 m) and holds 120,000 gal (454,200 L) of water. An elastomeric membrane lay-er provides waterproofing, and the ga-rage roof is tilted for drainage, says Nordenson.

Drainage and waterproofing were also critical concerns within the Bloch Building itself, especially for the 38,000 sq ft (3,500 m²) of vegetated and irrigated roof. The roof is designed to manage the building’s storm water while also providing a high insulation

value and sufficient thermal mass to sig-nificantly reduce the structure’s energy consumption.

At press time, the Nelson-Atkins’s Bloch Building was approaching its sec-ond anniversary. Thinking back to the design process that created this critically acclaimed structure, Nordenson mused on the concept of poché, the black lines on architectural plans denoting the sol-id walls that create the interior spaces in traditional Beaux-Arts structures, including the original Nelson-Atkins building. sha and Nordenson also thought in terms of poché for the Bloch Building, but with a twist. They used the walls of the structural and fluttering Ts to enclose the building’s mechanical systems as well as to form the interior spaces. Then they pulled these massive structures into the middle of galleries and lenses to “free the [glazed] perime-ters to be as crystalline as they are,” Nor-denson says.

Likewise, the creation of the wave T supports in the parking garage rep-resented a departure from the ordinary, something that Gipple sees as an essen-tial goal for today’s structural engineers. “It is easy enough to provide the tra-ditional solution,” he stresses, but the Bloch Building demonstrates what can be achieved when “engineers embrace the nontraditional.” CE

ProjecT crediTs

Owner: Nelson-Atkins Museum of Art, Kansas City, Missouri Architect: Ste-ven Holl Architects, New York City Local architect: bnim Architects, Kansas City, Missouri Structural en-gineer: Guy Nordenson and Associates Structural Engineers, L.L.P, New York City Associate structural engineer: Structural Engineering Associates, Inc., Kansas City, Missouri General con-tractor: J.E. Dunn Construction Com-pany, Kansas City, Missouri Mechanical engineer: Arup, New York City, and W.L. Cassell & Associates, Inc., Kan-sas City, Missouri Glass consultant: R.A. Heintges & Associates, New York City Landscape architect: Gould Ev-ans Goodman Associates, L.C., Kan-sas City, Missouri Lighting consultant: Renfro Design Group, Inc., New York City Geotechnical engineer: Terracon, Olathe, Kansas


Documents

Designed - MIT Architecture · It was 1999 and Steven Holl, the founder of New York City–based Steven Holl Architects (sha), was working with Guy Nordenson and Associates Structural