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In September 2006 the Orange County Performing Arts Center opened its 2,000-seat Renée and Henry Segerstrom Concert Hall and 500-seat Samueli Theater. The new structure is composed of three separate buildings under one roof and is designed for a minimum life span of 50 years. The concert hall’s basic acoustic form is a “shoebox.”
Courtesy Orange County Performing Arts Center, all |
The Orange County Performing Arts Center, located in Costa Mesa, California, strives to offer the residents of Orange County and Greater Los Angeles multipurpose facilities that by embodying the highest professional standards present the performing arts to best effect. In 1986 the center proudly unveiled the 2,000-seat multipurpose Segerstrom Hall, one of the nation’s most innovative and technically advanced venues of its time. In September 2006, the center completed a 290,000 sq ft (27,000 m²) expansion project that features two spectacular new venues: the 2,000-seat Renée and Henry Segerstrom Concert Hall and the 500-seat Samueli Theater.
In 2000 Henry Segerstrom, a real estate developer in Costa Mesa and the founding chairman of the Orange County Performing Arts Center, donated $40 million to be used to finance the concert hall that bears his name and the name of his late wife. The Samueli Theater is named in honor of Henry and Susan Samueli, Orange County philanthropists whose Samueli Foundation donated $10 million to the center in 2001.
The new structure comprises three separate buildings under one roof that are separated by 12 in. (305 mm) wide joints designed to accommodate rigorous seismic and acoustic requirements. Home to the Pacific Symphony Orchestra, the new concert hall was designed by the renowned architect Cesar Pelli, and its acoustic features were overseen by Russell Johnson, the chairman of the consulting firm Artec Consultants, Inc., of New York City. Additional facilities constructed as part of the expansion include a music library, two large orchestra chambers, eight individual rehearsal quarters, 15 dressing rooms, an education center that helps serve more than 300,000 student visitors each year, a 124-seat restaurant supported by a full-service professional kitchen and a catering kitchen, a large pedestrian plaza complete with a Richard Serra sculpture, and a heating and cooling plant.
In September 2003 the Orange County Performing Arts Center hired the engineering and construction firm Fluor Corporation, of Irving, Texas, to serve as the project’s general contractor. The guidance to the architect, acoustician, engineering and construction firm, and others involved in the project was simply to provide the facilities at a cost of no more than $200 million. Designed for a minimum life span of 50 years, the building also had to be compatible with the architecture and to incorporate finishes comparable to those of the existing performing arts complex.
The basic design of the primary spaces was established first by Pelli and Johnson, the structural design lagging slightly behind the architectural design, as required. The rectangular structure’s north elevation is “serpentine” in shape and enclosed by a signature curtain wall. Designed by Pelli, the wall includes a nearly 50,000 sq ft (4,600 m²) curved, laminated glass wall system that encloses the main lobby and three additional lobbies that serve the concert hall’s various tiers.
The main concert hall consists of one level below grade and five levels above grade. The levels above grade are distinguished by a maximum ceiling height of nearly 80 ft (24 m) from the orchestra level to the concert hall ceiling. These levels house the performance platform, fixed and movable patron seating, reverberation chambers, lobbies, a restaurant, rehearsal rooms, restrooms, dressing rooms, and support facilities. The level below grade houses mechanical and electrical rooms, storage space, a kitchen, theatrical lifts, and other support rooms. To accommodate requirements pertaining to acoustics and the theatrical rigging system, the roof consists of two structural levels—one located at the roof level proper, the other located at the concert hall ceiling level—with a full attic space between.
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The acoustic design of the concert hall, which is home to the Pacific Symphony Orchestra, focused on three major components: ultralow background noise levels, each room’s basic architectural acoustic form, and a series of devices that can vary the acoustic properties of a hall.
The Samueli Theater, which includes a small rehearsal room on the second tier, has one level below grade and four levels above grade. In addition to the theater itself, the various levels house musician lounges, restrooms, dressing rooms, and several mechanical and electrical rooms.
The heating and cooling plant consists of one level below grade and five levels above grade. The below-grade level houses the boilers, chillers, and other mechanical equipment. The above-grade levels house a café, mechanical and electrical rooms, lobbies, and other support facilities; the cooling towers are situated on the roof.
The structural slabs forming the orchestra level as well as the first through fourth levels are concrete slabs reinforced in a single direction supported by reinforced-concrete beams and walls. The columns also are of reinforced concrete. At the roof level, the structural slabs consist of concrete over metal decking supported by structural steel fabricated trusses. The acoustic requirements specified that the upper roof slab—above the steel trusses—have 6 in. (150 mm) of 4,000 psi (27,580 kPa) concrete over a 3 in. (76 mm) deep metal deck, for a total of 9 in. (229 mm). The lower roof slab—at the bottom of the steel trusses—was to have 4.5 in. (114 mm) of 5,000 psi (34,475 kPa) concrete over a 3 in. (76 mm) deep metal deck, for a total of 7.5 in. (190 mm).
The lateral-force-resisting system’s vertical elements take the form of cast-in-place reinforced-concrete shear walls. Meanwhile, cast-in-place reinforced-concrete slabs and deck slabs made of concrete and metal act as the horizontal diaphragm.
On the basis of recommendations made by the project’s geotechnical engineer—Leighton and Associates, of Irvine, California—the foundation slabs comprise 14 in. (356 mm) square piles of precast, reinforced concrete with pile caps and a monolithic mat slab. The pile capacities are 200 kips (890 kN) at a depth of approximately 50 ft (15 m).
Because the lowest level of the buildings is below the water table, it was designed to resist hydrostatic pressures. As a result, the slab on grade was designed as a structural slab, and the foundation walls are heavier than would have been required if a dewatering system had been provided. What is more, the structure’s design necessitated waterproofing requirements that were more extensive than if a dewatering system had been included.
The building is designed to meet the requirements for seismic zone 4 set forth in the building code released in 2001 by the California Building Standards Commission as well as the design load criteria from that code given in the following table.
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Design Load Criteria
Floor live loads: |
| Lobbies and corridors |
100 psf (unreduced) |
| Fixed seating |
50 psf (reducible) |
| Stage areas |
150 psf (unreduced) |
| Storage |
125 psf (reduced) |
| Back and front of house |
100 psf (unreduced) |
| Mechanical rooms |
125 psf (unreduced) plus pads |
| Roof |
20 psf |
| Special loads: |
| Wind loads (exposure B)* |
70 mph |
| Organ |
60,000 lb |
| Acoustic canopy |
>50,000 lb |
| Seismic loads (seismic zone 4): |
| Soil profile type SD |
I = 1.0, R = 4.4 |
Near-source factors
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Na = 1.0, Nv = 1.02
Ca = 0.44, Cv = 0.65 |
*As defined in ASCE 7-02. |
Slabs of cast-in-place, reinforced concrete and beams supported by cast-in-place concrete columns provide support for the dead and live loads of the floors. To sustain dead and live loads associated with the roof and attic levels, the building employs a composite steel deck covered by cast-in-place concrete and supported by steel beams and trusses.
Wind loads and seismic lateral loads are borne by concrete shear walls and floor framing acting as diaphragms. The latter loads are transferred to the ground by a concrete foundation mat and piles.
To accommodate acoustic requirements, special structural details were developed for the lateral support of the exterior masonry walls and masonry walls within “floating” elevator shafts, that is, shafts not connected to the main building so as to avoid transmitting vibrations to the structure.
The main lobby wall evolved significantly from the schematic design renderings when it became apparent that the vertical mullion structural scheme would produce a “cage” effect when viewed from either the exterior or the interior. To address this concern, the wind and seismic structural supports were reoriented in a horizontal direction to span between columns, and the lobby wall’s dead loads were supported by tension rods hanging from the roof. These changes were developed early on as a result of careful coordination with the project’s structural engineer—John A. Martin & Associates, of Los Angeles—and resulted in a more economical and transparent envelope.
Thermal studies showed that the standards for energy efficiency for residential and nonresidential buildings set forth in the California Code of Regulations (title 24, part 6) could be met without using insulating glass on the lobby wall. Therefore, laminated glass alone, with no vertical mullions, spans the 8 ft (2.4 m) between the wall’s horizontal pipe trusses. Only a 5/8 in. (16 mm) wide seal and joint interrupt a clear view inside and out.
Lastly, the design moved away from faceted glass to curved glass on six different radii, which transformed the “skin” of the wall into a fluid glass ribbon. From the outside, the reflections of adjacent buildings smoothly blend with views of the structure’s interior.
Extensive performance testing was done to ensure that the skin would be weatherproof and that it would be able to adjust to severe seismic displacements and meet all wind load requirements. In the end, the curves drawn by Pelli had the effect of highlighting the building’s horizontal direction, pointing the way to an integrated structural and aesthetic solution.
The roof structure consists of eight trusses that span the primary shear walls to provide the clear span required for the concert hall. The largest truss spanned nearly 110 ft (34 m) and weighed almost 90 tons (82 metric tons). The trusses were assembled in one piece off-site, trucked to the site, and installed in eight days by using a 1,400 ton (1,270 metric ton) mobile crane with 373 ft (114 m) of boom and jib. Before the crane was delivered, its planned location at the site was prepared to address the excess ground pressures that would be induced during the lifting operation. The crane’s path and the location from which it would operate were overexcavated by 5 ft (1.5 m), backfilled, and compacted in lifts to produce a pad that could withstand 5,000 psf (239.4 kPa) of ground pressures while the trusses were positioned. In advance of this operation, a detailed plan outlining the crane’s location and operating procedures was produced, reviewed by Fluor’s rigging engineers, confirmed by the owner’s soils consultant, and thoroughly discussed with the craftsmen before lift operations began.
The curving and cantilevered elements called for in the structure’s architectural design impart a flowing appearance. Moreover, height restrictions required that interstitial spaces be minimized, necessitating coordinated efforts on the part of the mechanical, electrical, and plumbing professionals. This process required nearly 18 months of intense effort involving the engineering and construction contractor, the architect, and other subcontractors.
Construction began on the project in September 2003 and lasted roughly 36 months. A storm-water protection plan was implemented and vigorously maintained throughout construction. Furthermore, a dewatering system used during construction pumped up to 1 mgd (3,785 m³/d) of groundwater into Costa Mesa’s storm-water system. To ensure compliance with the city’s requirements, the de-watering system employed a complex filtering system to cleanse the groundwater of traces of hydrocarbons and reduce elevated nitrogen levels.
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The north elevation of the rectangular structure is “serpentine” and is enclosed by a singular curtain wall, which includes a nearly 50,000 sqft (4,600 m2) curved, laminate glass wall system that encloses the mainlobby and three additional lobbies serving the concert hall’s various tiers.The curved glass transformed the “skin” of the wall into a fluid glass ribbon, above and below. |
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Once the shoring system was complete, work began on the dewatering; excavation; waterproofing; the foundations (which comprised 1,492 driven piles 50 ft [15 m] long and 14 in. [356 mm] in diameter with concrete pile caps); the 3 ft (0.9 m) thick mat slab; cast-in-place concrete walls, columns and elevated decks; steel trusses; the exterior envelope; the heating, ventilation, and air-conditioning system; and interior finishes. Building construction progressed north to south and bottom to top, with final cleaning and painting conducted from the top down. Two tower cranes were used to erect the primary structure and were supplemented with multiple hydraulic cranes for infill work.
As part of the requirements intended to lessen the project’s environmental effects, construction was confined to the hours from 7 am to 8 pm Monday through Friday and from 8 am to 7 pm on Saturdays, Sundays, and holidays. Moreover, the roads bordering the site had to remain open continuously and there could be no street parking. Pile driving was suspended several times so as not to disrupt weddings at the Wyndham Hotel, which is across the street.
The basement of the structure was surrounded by groundwater to within 7 ft (2.1 m) of finish grade. The excavation was accomplished by installing the dewatering system: a temporary groundwater well point system that was used to lower the local groundwater table by approximately 20 ft (6.1 m) in advance of excavation. Steel H beams were driven, followed by wood shoring as the excavation was accomplished. As the excavation neared rough elevations, pile driving commenced. Piles were cut to design lengths, and the building’s excavation was finely graded in sections working north to south. A 2 in. (51 mm) thick lean concrete “mud mat” was placed as each section was completed, and sheet waterproofing in the form of a composite of high-density polyethylene and bentonite was applied over the entire foundation plane and along the shoring system’s inside walls. At each pile, a metal closure plate was affixed to the pile to attach the waterproofing system. To provide additional protection, 2 in. (51 mm) of concrete was then placed on top of the waterproofing system. Once the waterproofing was fully protected by concrete, installation of the rebar for the structural mat slab commenced. On the exterior walls, shotcrete was applied to its full design depth over the waterproofing system, the wood shoring acting as a permanent form.
Many complications occurred during the construction phase. Amid shortages of structural steel, cement, and plaster, the foundations and superstructure were built during the second-wettest year on record in California. Moreover, the original structural steel contractor and the millwork contractor failed to complete their contracts and were replaced during construction. Fluor cleared these hurdles by means of additional manpower, additional shifts, and overtime during the final seven months of construction. Fluor and its partners were thus able to deliver the building on time for the gala opening.
Relying on more than three decades of experience in creating rooms that lend themselves to critical listening to amplified and nonamplified performances, Artec Consultants delivered superb acoustics in the new venues. The acoustic design includes three major components: ultralow background noise levels, each room’s basic architectural acoustic form, and a series of devices that can vary the acoustic properties of a hall.
Low background noise levels result from a combination of quiet infrastructure systems and the use of features designed to prevent outside noise from infiltrating the performance spaces. It is fundamentally important that the location of such noisy infrastructure as electrical transformers and major mechanical systems be considered from the outset.
In the Renée and Henry Segerstrom Concert Hall and the Samueli Theater, electrical equipment, chillers, boilers, major pumping equipment, and air handlers are housed within the sections of the building that are structurally isolated from the performance spaces. All of these spaces are located away from the concert hall, which meets the most stringent noise criterion, N1, meaning that no outside noise can be heard inside the hall.
Building services related to air, power, and water pass from the structure’s isolated sections and are routed to the spaces they serve on a system of devices that provide vibration isolation. The type and configuration of lighting equipment and air terminal devices, including return air grills and registers as well as linear diffusers, were selected so as to avoid generating noise in performance and rehearsal spaces.
The walls surrounding the performance spaces employ as substrate massive concrete or masonry coated with plaster to preserve sound energy within performance spaces and keep out noise. Where performance space walls are exterior walls, double-layer masonry is used. Doors into performance spaces are organized in vestibules with full-perimeter sound seals to enable personnel to enter and exit with minimal intrusion of lobby noise. Any openings made in the walls for the passage of ducts, conduits, sprinkler pipes, and temporary signal cabling were fully caulked and sealed.
The concert hall’s basic architectural acoustical form is a “shoebox.” Despite the hall’s modern, curvy visual aesthetics, its basic acoustic form is similar to the classical rectangle, as in Vienna’s Musikvereinssaal or Boston’s Symphony Hall. Believed to have developed partly to address limitations in designing column-free spaces for assembly, the rectangular form resulted from the fact that room width, more so than room length, was limited historically by the span of the longest truss available at the time. However, the rectangle’s long, narrow shape is well suited to supporting strong lateral sound reflections. Along with a large air volume resulting from the room height of nearly 80 ft (24.4 m), the narrow width provides acoustic intimacy, clarity, and strong sound impact while developing and sustaining reverberance.
The multiple ledges that surround the concert platform and audience areas result in additional reflections of sound to the stage and the largest seating areas. This feature facilitates on-stage communication between sections of the orchestra and increases the overall immediacy and spatial presence for the audience.
Classical music repertoire spans several centuries, and recent decades have seen amplified performances in virtually every concert hall space. Several devices that can vary acoustic properties are incorporated into the architecture of the Orange County Performing Arts Center so that the natural acoustics can be tailored to particular genres and can address the special acoustic needs of amplified performances.
Three types of acoustic devices are used in the concert hall. The first is a system of three canopies that vary in height over the concert platform in a way that makes it possible to adjust on-stage acoustics and provide a method of balancing the sound from the various sections of the orchestra. For smaller ensembles with weaker sound levels, the canopies can be lowered to provide more acoustic support and provide a more intimate setting on stage. To accommodate greater sound levels on the stage, the canopies can be set at higher elevations to control loudness. In amplified works or organ performances, the canopies can be positioned at their highest setting to afford an unobstructed view of the organ or video screen or to reduce the extent to which stage monitors can be heard in the audience areas.
The second acoustic device takes the form of four large volumes, or reverberation chambers, flanking the main volume of the concert hall—two at the south end of the room adjacent to the choral loft and two at the sides of the room adjacent to the primary audience seating areas. These volumes are cut off or partly or fully coupled to the main volume through a series of 120 doors of solid concrete varying in height from 4 to 11 ft (1.2 to 3.4 m). Opening the doors allows sound into the secondary chambers, significantly varying the length and loudness of reverberation with minimal effect on the tonal balance of the source performance. The chambers can increase clarity while maintaining or increasing reverberation time and can help improve clarity in amplified works without eliminating reverberance. This technique is especially effective for symphonic performances, which frequently showcase an amplified performer with orchestral backup in which the individual orchestral players have minimal amplification.
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The curtain wall is especially dramatic after dark, as interior illumination underscores the serpentine architectural form of the north elevation. |
The final acoustic device provides two systems of acoustic draperies: a set of curtains deployed to cover the walls of the main concert hall volume and a set of banners extending from the attic to reduce reverberation in the four secondary chambers. Small adjustments in fabric help tailor reverberation to reveal nuances or textures of densely scored symphonic works. Large exposed areas of fabric allow absorption of high sound levels in heavily amplified performances and can be useful in recording sessions or broadcast events.
Designing and constructing world-class performing arts venues to meet the highest expectations and standards of performers, community leaders, and audiences present exceptional challenges and opportunities. Harmony among the many professionals and enterprises involved in making world-class venues a reality is absolutely critical. In the end, the ultimate reward for their teamwork is knowing that generations of arts enthusiasts will witness the greatest artists and performing arts companies in the most technically advanced settings.
Darrell E. Waters is the vice president of operations for the industrial and infrastructure business group within the Fluor Corporation, of Irving, Texas. He was the project director for the Renée and Henry Segerstrom Concert Hall and the Samueli Theater.
Project Credits
Owner: Orange County Performing Arts Center, Costa Mesa,
California
Primary architect: Pelli Clarke Pelli Architects, New Haven, Connecticut
Contractor: Fluor Corporation, Irving, Texas
Architect of record: Gruen Associates, Los Angeles
Acoustician and theater planner: Artec Consultants, New York City
Structural engineer: John A. Martin & Associates, Los Angeles
Mechanical engineer: Arup, Los Angeles
Electrical engineer: FBA Engineering, Newport Beach, California
Geotechnical engineer: Leighton and Associates, Irvine, California
Civil engineer: RBF Consulting, Irvine, California
Landscape architect: Peter Walker and Partners Landscape Architecture, Inc., Berkeley, California
Lighting design: Cline Bettridge Bernstein Lighting Design, Inc., New York City
Food service consultant: Cini-Little International, Inc., South Pasadena, California
Curtain wall consultant: Israel Berger & Associates, Inc., New York City
Code and life safety consultant: Rolf Jensen & Associates, Inc., Chicago
Elevator consultant: Lerch Bates and Associates, Littleton, Colorado
Graphics: Pentagram Design, Inc., New York City
Hardware consultant: Finish Hardware Technology, North Hollywood, California
Specifications writer: Construction Specifications, Inc., Thousand Oaks, California
Waterproofing consultant: Roofing and Waterproofing Forensics, Inc., Yorba Linda, California