The General Office Building utilizes spread footings in combination with exterior strip footings, which support basement walls. The spread footings beneath individual columns range from 2 ft. to 3 ft. thick. Along the northern and western edges grade beams connect the interior foundations to the exterior strip footing. The perimeter strip footing’s 2 ft. 3 ft. thickness supports a 2 ft. thick foundation wall. To resist overturning in the two shear wall cores 4 ft. thick mat foundations stretch out to connect with column foundations.


Floor Construction


An expansion joint in the connecting walkway separates the two portions of this office building; the auditorium is to the west and the main building is to the east. The three-story auditorium is supported by 4 1/2 in. concrete on non-composite metal deck, w-shape beams and round HSS posts. To create the complicated curved slab edges of the main building portion a concrete two-way flat slab was chosen. A majority of the building utilizes 8 in. slabs. Larger congregation areas have increased thickness of 12 in., and mechanical rooms have even larger 16 in. slabs. Drop panels provide the required punching shear and negative moment capacities at all floors. Each floor is supported by both rectangular and circular concrete columns.



























Lateral System

The General Office Building resists lateral loads through a series of concrete shear walls. The auditorium has 10 in. thick curved shear walls hidden in the exterior walls and around the stair tower. In the main building a shear wall tower encloses the elevator shaft and another encloses the stair tower. These eight 12” walls are integrally poured with the two-way slabs and thereby receive gravity loads.












Fire Protection

The entire building is fully sprinklered to comply with local and national codes. The two parking levels utilize a dry system to prevent water from freezing in the pipes. The superstructure employs a wet system for faster fire suppression. In the three computer rooms FM-200 gas sprinklers are deployed to prevent the spread of electrical fires. Siamese connections along Spring and Cameron streets allow the fire department to feed water into the three stairwell standpipes.  Third floor sprinklers create a water curtain to protect the three-story atrium.















The entire building’s heating emanates from four 75 GPM boilers located in the lower basement. Also in the lowest level are two 150 ton centrifugal chillers and a smaller 30 ton scroll chiller. The water from these systems is piped up the riser tower, which is attached to the northern side of the east stair tower.

The room-heated water is sent to the penthouse where it is cooled by the forced draft cooling tower. This newly cooled water is then sent back down to each air handling unit. Every floor is serviced by a separate variable air volume air handler (VAV), each having a capacity between 5,400 and 18,700 CFM.  These units are located on the upper basement, third, fourth, and sixth floor with some units servicing a floor above their location. Two of these VAV units located in the Unitherium first floor service that section of the building. 

Also in the conference room's mechanical room is an energy recovery wheel. Another, larger energy recovery wheel is located on the third floor and handles the air flow for the entire main building.  Both of these recovery wheels are designed to be over 70% efficient, resulting in huge energy savings. A 130 GPM plate and frame heat exchanger located in the lower basement allows the building to utilize free cooling under certain conditions.  
























The General Office Building's power is supplied from two 460Y/265V basement transformers. This differs from the standard 480Y/277V transformers because the power is being supplied from a city. From the underground collector bus the lines travel to 3000 amp main switchboard located in the lower basement. The main switchboard has a 1200 amp frame with a 1000 amp trip and is 100% rated. The more expensive 100% rating was chosen because the typical 80% rated would force an increase in the frame size. The main switch board sends the electricity to seven different 400 to 1200 amp distribution panels, most of which are 600 amp units.

In an emergency three automatic transfer switches transfer the power supply from the public lines to the 500 KW generator. To protect the digital information stored in the server room, a 60 KW uninterrupted power supply (UPS) is stationed on the sixth floor.  During the few seconds before the generator starts to supply power in a blackout this UPS system will supply battery-stored immediate power.






















The lighting for this office building varied from space to space to meet the occupancy’s needs. The primary luminaire used is a 6 in by 4 ft. long recessed fluorescent luminaire. This was the primary lighting in all offices and corridors because of its low cost and minimal impact on the space.  To light the three story signature atrium, several 3 ft. long LED stick fixtures hang from the ceiling and emit a warm white light.


The auditorium was given special attention by the lighting engineer because that was the conference room where United Therapeutics will introduce and market their latest cardiovascular medicines.  Incandescent track lights and theatrical luminaires light the presenter at the middle of the space while flexible linear LED luminaires illuminate the seats from above. Completely surrounding the audience is a color changing LED mesh unit, which will be able to completely immerse the audience in cardiovascular world.





















To achieve this design DPR Construction Inc. submitted a winning bid of $40 million. DPR broke ground in August 2010 and expects substantial completion in December 2011. The project was completed using a single prime design-bid-build contract between the owner and the contractor.

Standard cast in-place concrete construction was used to erect this building. A single tower crane, located in the plaza, lifted the material into place. Contractors then built the plywood forms and placed the reinforcing. The concrete was pumped from street level by truck into these forms. Each floor plate was poured in two stages with a construction joint running in between the stair towers. A large expense in the project was the erection of temporary scaffolding to support the fourth floor above the atrium.



















The vertical circulation in Unither is comprised of three elevators and three stairwells. Theauditorium wing has a 3500 lbs. traction elevator and fire stair in the south west corner. In the main wing two 4000 lbs. traction elevators are housed in a single bank. Two centrally located stair towers service the main wing and provide the minimum egress distances for fire safety.













The telecommunication service lines enter the building at the upper parking level and are distributed to the fourth floor main data center by four 4 in. conduits, where it is then distributed to the telecom rooms on each floor.  The fourth floor server room houses 11 separate server racks to store the company’s sensitive product information.