Pre-cast cells for jail: One man's ceiling is another man's floor

By BART ARENSON
Special to the Journal

The jail cells at the soon to be finished Two Rivers Correctional Institution in Umatilla, Ore., began life as 488 precast concrete modules fabricated by Bethlehem Construction in Cashmere, Chelan County. Producing about four a week, the company took nearly a year and a half to cast and ship the modules along with 797 ancillary slabs, planks, walls, beams and columns.

When the building is complete this November, 1,600 inmates will call the cells home. "Precast was a choice for durability and flexibility; it gave us the ability to use the basic cell structurally," said Laurance Glasser, project architect and construction administrator for HOK, the prison's design firm.

"We could use it in the building's structural system since part of the cell participated in load bearing."

The modular cell blocks were the first package bid for the $129 million medium-security prison. The joint venture of Drake/Dunn acted as general contractor/construction manager (GC/CM) for the project and let the bid packages. An Oregon firm underbid Bethlehem, but because of bonding and other problems, it opted out early in the engineering phase. Bethlehem stepped in to fulfill the contract, which after change orders amounted to about $5.5 million.

Tom Pattison, Bethlehem's vice president of Construction Management, ran the job. "We had projects of this size and value, but never of this duration," he said.

Three basic cell types were cast: a single unit, a double unit and a

Handicapped-accessible unit. "The average double cell weighed close to 56,000 pounds," said Pattison. "We purchased three low boys in order to ship the units." Once production was under way, Pattison says his crew aimed to complete a casting every day.

The cells were cast in forms built by a specialty form builder,

Helser Industries of Portland, and leased to Bethlehem by the state of Oregon. The state retains use of the forms for future units.

The steel forms had hydraulic systems, allowing them to move both outward or collapse inward for removal of the cast cell. "The inner chamber of the form collapsed about 5/8-inch; the outer walls of the form were on tracks, rolling back and away about four feet," said Pattison.

Pattison says before a line pump was used to fill the forms with the

concrete mix, the outer walls were rolled away so any inbeds, blockouts, reinforcement or electrical conduit could be set for that particular cll type.

The basic double cell was made up of two forms, a lower and upper piece. The bottom half of the double cell had to be cast upside down in order to slip off the form correctly. The open end would eventually become the cell's ceiling, but the extreme weight of the unit made getting the floor of the cell right side up a ticklish operation.

"Once that piece was cast and pulled out by a crane, it was put into a flipper," said Pattison. The flipper consisted of three circular steel rails on rollers that held a box designed to fit the jail cell. The box was supported by the spherical steel frame. "After the piece was in the flipper and the flipper was bolted together, then we would roll it over," said

Pattison. "It had a cable-like a yo-yo; pulling it flipped the cell over so that when we removed it from the flipper it was right side up."

At the building site the individual cells were stacked, making a lower and mezzanine level in each housing unit. Bethlehem also cast a precast plank to separate the two levels.

Glasser says that plank fit the old song lyric, one man's ceiling is another man's floor. "The bottom cell sat on a continuous footing, right on grade, but you didn't need a floor on the upper cell because it rested on the plank," he explained.

"Once we designed the primary cell module, we designed the entire building around it. It made erection of the cells very quick." The modular nature of the individual jail cells also allowed the architect to design a floor plan that maximized the visibility of supervisory personnel and allowed for service and maintenance to be completely separate from the secure inmate population.

"By design features that minimize the staff and maximize the level of security, the prison is able to reduce annual operating costs." said Glasser.

Each of the 14 medium-security housing units has 52 cells, its own

dayroom, officer station and ancillary support rooms. Four of the housing units are designed to fit together into a bow tie shape. This configuration enabled the cells to be grouped adjacent to each other with a five foot space in between.

"This space is the service core and plumbing chases," said Glasser. "The advantage was to keep all the mechanical access into a chase zone; so you will not have to interface maintenance people within the housing unit."

"There is a complete separation between secure areas and nonsecure areas of the prison," he said.

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