Tobin Center for the Performing Arts Building 6 (Over 75 Million Dollars) Project Description The Project consisted of the complete renovation of the historic Municipal Auditorium s treasured façade while incorporating a new 183,000 square foot, six story, and multipurpose performance arts hall into its framework. The Municipal Auditorium was originally constructed in the late 1920 s and was dedicated to World War 1 veterans. The north side of the site borders the San Antonio River Walk and contains a plaza where Medal of Honor recipients who had an association with San Antonio are honored. In the spring of 2011 Linbeck / Zachry Joint Venture was selected as the Construction Manager at Risk on the project. The Linbeck / Zachry Joint Venture was formed to combine the strengths of two 75 year old companies and local contracting experience. The Linbeck team brought large, complex and performing arts experience together with Zachry's extensive San Antonio and complex project experience to form a cohesive integrated project team. Linbeck / Zachry Joint Venture s early involvement in preconstruction services allowed the Owner to realize some savings options that led to greater program opportunities. During the preconstruction phases we priced numerous design schemes for the size and architecture of the building in order to select the optimum design solution for the project. Those schemes included the total tear down of the Municipal Auditorium and the "raising of the existing roof" which would renovate the existing building. Ultimately integrating the historical façade and entry with a new structure adjacent to the old was deemed 1
the most viable. Our contract with the client was a guaranteed maximum amount with fee at risk. The terms included savings to be returned to the client. We were able to manage the cost so that we identified savings that were returned early and the client was able to add enhancements during the course of the project. Difficulty in construction resulting from design, location, materials; The newly opened Tobin Center for the Performing Arts is more than a state-of-the-art performance venue rivaling the best in the world. It was also a case study in complex construction projects. The Linbeck Zachry JV faced a multitude of unique situations in constructing the ultra-modern facility, which includes a 1,750-seat performance hall, a 250-seat studio theater and an outdoor performance plaza. Performance Hall inside an Existing Structure: The team built the new center inside an existing historic structure, in an extremely tight footprint in busy downtown San Antonio, on the edge of the San Antonio River, while meeting the strict requirements necessary for construction of a world-class venue for music and theater. 2
Performance halls by their very nature are some of the more complicated construction projects, the preservation of a portion of the original structure and its integration with a completely new, state-of-the-art performance center made this an even more challenging project. The construction process, which began in May 2011 and culminated with the doors opening on September 2014, was a painstaking exercise in precision. That began with the demolition of the Municipal Auditorium while preserving the building s original Spanish Colonial Revival-style front and side façades. Downtown Location: The location of the Center created additional challenges. First, the job site had an extremely tight footprint in a congested area of downtown San Antonio. There was no laydown area for the temporary storage of supplies. Both firms are strong supportters of LEAN CONSTRUCTION principles and are experienced in the use of the LAST PLANNER. These construction management techniques were used throughout the project. Delivery of materials were completed on a strict just in time basis so they could be installed soon after arrival. The site had three acres of property and 2.5 acres of building. This extremely tight footprint required the team to closely coordinate manpower, equipment, and material deliveries. Secondly because we were on the San Antonio River and near multiple active businesses we had to make valiant efforts to be good neighbors during construction. Examples include a vehicle wash station that all vehicles exiting the site had to go through, shrouding of light fixtures on the tower cranes to minimize light pollution, late morning demolition start to minimize noise issues, and maintenance of street/ fences for egress into and around the site. On the River: The site s position on the south bank of the San Antonio River meant that piers and sub-foundations were below the river level. We lowered the water table within the building footprint by use of pumps. This created a dry work area for the foundation work. The water discharged from the construction was all run through a process of filters and settlement tanks before allowing discharge into the river. Differing Site Conditions: Early in the project before demolition of the existing building was to begin a differing site condition was discovered that had the potential of a significant delay. It was discovered that a major high voltage, buried, electrical transmission line traversed the site. The existing location would pass thru the new building's lower level. We ultimately developed a construction sequence that allowed the demolition of the existing building and the excavation for the new building to commence without a significant delay to the project schedule. By working with our trade partners we were able to eliminate any additional construction cost to the Owner. 3
Unusual Construction Techniques Involved Existing Structure Reinforcement- Movement Monitoring The team reinforced the U-shaped façade to help it withstand the demolition of the rest of the auditorium. Throughout the demolition and through the structural steel and concrete construction stages we monitored the existing limestone for vibration and movement. This was done by the installation of vibration gauges and laser surveying of the existing building before the constructing began and then after it was complete. No detrimental movement occurred. Laser Scan and Modeling While 3D modeling is increasingly common in construction, it was a necessity for this project due to the complexity of tying into the existing historic piece. The team elected to complete a full 3D laser scan of the historic structure, which was then formatted into a fully integrated model. This allowed the trade partners and the design team to coordinate how the structure and rooflines would tie together into existing ones. Linbeck / Zachry Joint Venture closely coordinated the modeling effort with all of the trade partners on site with weekly modeling reviews. The entire structure was built three-dimensionally in the model prior to fabrication and field installation. Linbeck / Zachry Joint Venture employees conducted BIM coordination meetings weekly on the job site for over nine months. This coordination effort was used to fabricate the structural steel and to fabricate and install the ductwork, pipework and electrical conduit. This process eliminated major "clashes" in the field and resulted in a more productive installation. 4
Unique Acoustical Requirements The complex important acoustical requirements command the attention of almost all construction processes performed. The air conditioning systems are to only be felt, not heard, in a concert hall. To achieve that, the air velocity is very low and therefore the distribution systems are larger than normal. The ductwork is all internally insulated and most are enclosed in an acoustical enclosure to further manage unwanted noise. Electrical and fire protection systems on most project types are installed generally in the shortest and most direct route. The goal in a performance hall is to accomplish the same thing; however given the architecture of the building with the high ceilings and open areas in the audience chamber and stage house that path involves many twists and turns to get to the required location. Primarily for acoustical reasons interior partitions are constructed from floor to the structure above verses merely above the ceiling. The intersection of the partition to the structure is treated with a special detail for acoustical and/or fire and smoke control. Special details are implemented when pipe, ducts, and conduits must pass through the acoustical rated walls and floors. All of the preceding systems and items require close coordination to be able to fit within the minimal spaces allocated and the architecture demands for the project. Education to the Craftsman Due to the infrequent construction of this building type within a local area; the craftsmen and subcontractors are not familiar with the unique construction requirements. Given our experience in constructing performance arts halls; we recognize that lack of familiarity and took great effort to educate the subcontractors and the craftsmen of the special needs for this project. We produced specific instructions to bidders in our invitation to bid packages defining exactly how the work needed to be performed. Once the subcontractors were on site; we introduced them to the unique terminology required to effectively understand the building type. Examples are "AIJ " Acoustical Isolation Joint, a very critical item for isolating sound which might transfer through the structure; the difference between "house left" and "house right" verses "stage left" and "stage right". These informational sessions were conducted in concert with the specialty consultants; the acoustician and the theatrical consultant. Operable Floor System The Tobin Center is unique in that it also includes a $10 million moving flooring system, the first of its kind in the nation, consisting of rows of seats on a series of lifts that allow the seating configuration to go from a flat floor to a raked configuration at the push of a button. Increased uses result in increased revenue. A moveable floor allows the seats in a typical audience chamber "sloped" configuration to be mechanically rotated and stored under the floor. The floor can then be reconfigured into 12 predetermined configurations. The most frequent configuration is a flat floor that is raised to the stage 5
floor level so that the chamber and stage floor are one large contiguous floor. This configuration allows for banquets, trade shows and other events where a flat floor is desired. The floor utilizes existing spiral lift technology, typically used to elevate orchestra lifts. Added to that technology are moveable bases which the fixed theater chairs are attached. These bases rotate and allow the chairs to be stored below the floor. Gala Systems from Canada was hired to design, fabricate and install the moveable flooring system. Their design and construction work had to be coordinated with multiple disciplines starting with the structural slab at grade and continuing through the installation of flexible fire detection and suppression systems. Those systems can function in any of the floor configurations. Construction challenges began with coordinating the 30 spiral lift locations with the 15" thick concrete slab that contained 2'- 6" deep beams at the location of the lifts. During the reconfiguration the seats rotate on a base and are stored upside down under the floor. This required detailed engineering and coordination with the seating manufacturer, Series Seating. The biggest challenge with the seats is that when they rotate the seat pans stay in a vertical position and do not become horizontal. Becoming horizontal will put them in the way of the adjacent moving floor and damage the seat. The finish floor material for this system is an engineered wood floor system. The wood was installed to allow for the minimum clearance between the lifts of 1/4". The gap from the end of the each lift to the adjacent wall was also 1/4". This floor installation required close coordination with other aspects of the project since it could not be installed unless the humidity within the chamber was controlled to prevent expansion of the floor material during and after its installation. The supply air for the chamber occurs through 300 floor grilles. These also had to be coordinated with the operable floor system. The transformation between configurations takes approximately 25 minutes. The floor has been reconfigured numerous times since the building opened and different events have been held with different floor configurations in the same day. The installation of the system at the Tobin has been a huge success. 6
Operable floor system (photos) Building Cross Section of Operable Floor Raked Seating Configuration Flat Floor Configuration 7 Gala Configuration
Final Appearance and Quality of the Finished Product World Class Facility to Rival any Performance Hall in the World was the Goal. The expectation of the quality of construction was established early on from everyone involved. The design team had very specific requirements on the final quality and appearance. Given our experience, we knew the most difficult detail to construct was the fascia on the audience chamber balcony fronts. These not only function as an architectural element but also as an important part of the acoustical design of the audience chamber and provide fall protection to the occupants. The fascias were constructed of perforated wood panels backed by an acrylic panel with LED lights behind. This component must comply with strict code compliance for handrail height while not conflicting with the seating sight lines. The initial design of the fascia at Tobin was to prefabricate millwork "light boxes" that would be assembled off site. We developed details that would allow for a more constructible approach to handle construction tolerances of the concrete and steel structure including deflection that would occur in the cantilevered balconies. The final installation is in strict code compliance, provides for the desired sight lines, is a stunning architectural feature, and was installed without rework due to unforeseen issues with the structure. 8
Timeliness of Completion The date for the opening performance was established early in the construction process. We achieved substantial completion and occupancy of the building two days before that established in our contract. The grand opening event occurred on September 4, 2014, on schedule and was a huge success. We were able to achieve this ambitious schedule established at the beginning of the project inception despite the JV processing over 2,200 submittals, 560 items of change and 1,200 Requests for Information. The Performance Hall was built on time, in budget, incorporating cutting edge technology while maintaining the original historical significance of the Municipal Auditorium. 9