BergerABAM is a consulting firm offering services in the areas of planning, civil and structural engineering, environmental services, public involvement, construction management and support, surveying, and underwater inspection services.
JANUARY 2014 ISSUE 52 WINTER www.abam.com Containing Chernobyl Nuclear Power Plant On 26 April 1986, the worst nuclear power plant accident in history occurred at the Chernobyl plant in Ukraine (at the time, part of the Soviet Union). The destruction of Unit 4 sent highly radioactive fallout over Belarus, Russia, Ukraine, and Europe. The object shelter (OS)—a containment sarcophagus made of more than 7,000 metric tons of metal and 400,000 cubic meters of concrete—was built in December 1986 to limit exposure to radiation. Lifespan of the OS as part of an integral facility is not defined. The strength and stability only of some OS bearing structures has been identified as approximately 30 years. The first priority measures to stabilize the structures were implemented in 2005 to 2008. As a result of OS light roofing repair, the area openings decreased from 1,000 to 100 meters 2 , which respectively reduced uncontrolled radioactivity releases into the environment. The shelter implementation plan (SIP) for the conversion of the OS into an ecologically safe environment and system was initiated by a group of experts from Ukraine, the United States, and the European Union in 1997, which included the design and construction of a new safe containment (NSC) structure to be built that would last at least 100 years. A donor community, consisting of 46 countries and organizations, supports the work of the SIP. Funds are administered by the European Bank for Reconstruction and Development. The facility owner is the Chernobyl Nuclear Power Plant (ChNPP). Oversight of SIP work is provided by a project management unit staffed by representatives of ChNPP and a consortium of Bechtel International Systems Incorporated and Battelle Memorial Institute. An international tender was initiated in 2004 for the design, construction, and commissioning of the NSC structure. The contract was awarded in 2007 to NOVARKA, a joint venture between VINCI Construction Grands Projets and Bouygues Travaux Publics. NOVARKA subsequently awarded Rendering of the carriage and mobile tool platform. Image courtesy of PaR Systems, Inc. (continued on page 2) INSIDE/ OUT NEWSLETTER
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JANUARY 2014ISSUE 52 WINTER
www.abam.com
Containing Chernobyl Nuclear Power Plant
On 26 April 1986, the worst nuclear power plant accident in history occurred at the Chernobyl plant in Ukraine (at the time, part of the Soviet Union). The destruction of Unit 4 sent highly radioactive fallout over Belarus, Russia, Ukraine, and Europe.
The object shelter (OS)—a containment sarcophagus made of more than 7,000 metric tons of metal and 400,000 cubic meters of concrete—was built in December 1986 to limit exposure to radiation. Lifespan of the OS as part of an integral facility is not defined. The strength and stability only of some OS bearing structures has been identified as approximately 30 years. The first priority measures to stabilize the structures were implemented in 2005 to 2008. As a result of OS light roofing repair, the area openings decreased from 1,000 to 100 meters2, which respectively reduced uncontrolled radioactivity releases into the environment.
The shelter implementation plan (SIP) for the conversion of the OS into an ecologically safe environment and system was initiated by a group of experts from Ukraine, the United States, and the European Union in 1997, which included the design and construction of a new safe containment (NSC) structure to be built that would last at least 100 years.
A donor community, consisting of 46 countries and organizations, supports the work of the SIP. Funds are administered by the European Bank for Reconstruction and Development. The facility owner is the Chernobyl Nuclear Power Plant (ChNPP). Oversight of SIP work is provided by a project management unit staffed by representatives of ChNPP and a consortium of Bechtel International Systems Incorporated and Battelle Memorial Institute.
An international tender was initiated in 2004 for the design, construction, and commissioning of the NSC structure. The contract was awarded in 2007 to NOVARKA, a joint venture between VINCI Construction Grands Projets and Bouygues Travaux Publics. NOVARKA subsequently awarded
Rendering of the carriage and mobile tool platform. Image courtesy of PaR Systems, Inc.
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a subcontract of the basic and detailed engineering, procurement, manufacture, factory acceptance tests, delivery, and erection of the complete main cranes system (MCS) to PaR Systems, Inc. in May 2010. BergerABAM is part of this effort to create innovative solutions for containment, cleanup, and recovery while protecting workers, the surrounding communities, and the environment from the continued high radiation levels. As a subcontractor to PaR Systems Inc., BergerABAM is responsible for the structural analyses of the MCS under operational and seismic loading.
According to the design solutions, the NSC steel arch dimensions of the NSC structure are as follows.
• Maximum height - 110 meters
• Length from east to west - 164 meters
• Width from north to south - 270 meters
The main NSC bearing structure consists of 16 steel arch trusses (chords) assembled at a12.5-meter pace. The 16 steel arches are composed of a lattice structure of circular section tubes. Because of the dangerously high levels of radiation still emanating from the ruined reactor site, the NSC structure must be built away from the reactor to protect construction workers. The NSC will then be slid a distance of three football fields over the failing OS on a runway system, making the NSC the largest moveable structure in history.
Hanging just below the ceiling of the NSC structure, approximately 80 meters aboveground, are two 96-meter bridge cranes supported on six runways, top running, under hung design. The bridge cranes will be remotely operated from a control room located in a building separate from the NSC structure. The remote-controlled cranes will be used to safely dismantle the OS, with workers manipulating these cranes using cameras.
Telescopic crane arms normally used for remotely controlled applications could not be used because the size and length necessary to handle the very large deconstruction loads would make the cranes unstable. Instead, the cranes use three different carriages listed below.
1. A classic carriage with 50-ton hoist capacity.
2. A secure carriage with 40-ton capacity (personnel)/50-ton capacity material that may be used to transfer maintenance personnel around the facility in a shielded box.
3. A unique device called the mobile tool platform (MTP) carriage, a tensile truss structure that is mounted below a carriage.
The tensile truss structure is used as a stable platform for robotic manipulators and other remotely operated tools, which help dismantle and transport the debris. The MTP design provides sufficient stiffness while still having the maneuverability needed for remote tooling. Six independent wire rope hoists achieve the long vertical reaches necessary to transport and handle the debris generated by the deconstruction of the OS.BergerABAM analyzed the seismic and operational loads these cranes would have to handle, thereby helping to create the computerized control system necessary to keep the platform’s movements well constrained. This constraint is achieved by keeping all six ropes in tension, thereby making the system behave like a rigid truss structure—ideal for operating and manipulating heavy tools. The MTP is the largest known implementation of tensile truss design, and the first of this size to be used in recovery operations.
The MCS subcontractor, PaR Systems, is making significant progress in the fabrication and assembly of the various components and getting ready to commence the factory accepting testing program. The shipment of the MCS components is scheduled in March 2014.
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How can we create a more multimodal future? How do we fund our transportation infrastructure? That was the emphasis of the 24th Annual “Focus on the Future” Conference presented by California’s Self-Help Counties on 17 to 19 November 2013 in San Diego, California. Every year, the Focus on the Future Conference provides a forum for Self-Help Counties and other transportation agencies, elected officials, and the private sector to share experiences, highlight upcoming projects, and interact; it is the premier transportation conference in California.
The Self-Help Counties Coalition (SHCC) is the organization of 20 local county transportation agencies delivering super majority voter-approved transportation sales tax measures throughout California. SHCC member agencies are dedicated to keeping the faith of the voting public who provide the authority and the funding so that they may deliver the priority transportation projects Californians depend upon every day. SHCC, as an organization, is dedicated to ensuring sound public policy so that the State of California can meet its transportation infrastructure needs. SHCC works closely with the California Transportation Commission (CTC), the California Department of Transportation (Caltrans), elected officials, and other public and private sector interests.
This year’s three-day Focus on the Future Conference featured presentations on How to Pay for the Future Needs of California’s Growing Infrastructure; Increasing Mobility, Expanding Access, and Providing Options to the Traveling Public; Environmental Streamlining: The Road Ahead for California; Avoiding the Perils of Public Private Partnerships; Intelligent Transportation Systems Deployment; and an update on California’s High Speed Rail.
Notable speakers included Malcolm Dougherty, director, Caltrans; Andre Boutros, executive director, CTC; Brian Kelly, secretary, California State Transportation Agency (CalSTA); Jim
Earp, executive director, California Alliance for Jobs; and a special presentation from Daniela Bremmer, director of Strategic Assessment, Washington State Department of Transportation. As a conclusion to the conference, attendees were invited to join the executive directors from all the Self‐Help Counties as they discussed the various issues and wrapped up the 2013 conference.
As a consulting firm dedicated to addressing the many facets of our modern transportation system, BergerABAM was an enthusiastic participant and sponsor of the conference. BergerABAM provides the expertise and sensitivity that is critical in dealing with the controversial issues that often surround transportation improvements.
BergerABAM’s engineers work conscientiously to keep abreast of the changing political environment and federal investment programs. BergerABAM’s personnel understand these programs and their impact on regional and state transportation programs, and this knowledge provides an invaluable benefit to our clients.
Focus on the FutureFirm Sponsors California Transportation Conference
BergerABAM conference participants pictured from left to right, Abby Wood, Ruba Zumut, and Jeff Cross.
In BergerABAM’s ongoing commitment to small business contracting, the firm participated in the Prime Contractor Awards and After-hours Reception event on 14 November 2013. Held at the Maritime Event Center at Pier 66 on Seattle’s waterfront, the event provided prime and subcontractors and architectural and engineering firms an opportunity to network in a casual and engaging atmosphere. BergerABAM strengthened existing relationships and forged new ones with local small and disadvantaged businesses. The event also recognized three prime contractors as champions who made great strides in championing small businesses during 2013. This fourth annual event was hosted by the Washington State Department of Transportation, Sound Transit, and the Port of Seattle.
Commitment to Small Businesses
As the world’s energy consumption moves toward the use of natural gas rather than coal and oil, transporting large amounts of natural gas is increasingly important because of the increased demand for this type of fuel. An efficient way of transporting large quantities of natural gas, if pipeline is not available, is to transform it into a liquid for storage and shipment to destinations around the world.
One of the difficulties of transporting natural gas is precisely because it is a gas or “vapor.” Because gasses are less dense than liquids or solids, they occupy more volume than either of the other two substance phases. For instance, a quart of steam (water vapor) will transition into a much smaller amount of water once cooled into a liquid. Liquefied natural gas (LNG) also takes up less room than vapor natural gas—1/600ths
of the volume of the vapor. By cooling to cryogenic temperatures about -260 degrees Fahrenheit at ambient pressure, the now liquefied gas can be stored in large tanks as much as 190,000 cubic meters (6,700,000 cubic feet). From there, the fuel is transported to its destination, then warmed back to a gaseous state for general use.
Storing LNG is expensive, as the tank has to be able to operate at cryogenic temperatures and provide enough insulation to maintain the low temperature. Currently, conventional storage technology uses a 9 percent nickel steel construction for the inner storage tanks with a prestressed concrete outer wall. Unfortunately, this type of steel is expensive to produce and supply, and is available from only a few mills in the world. In addition, the number of contractors able to build these steel tanks have not kept pace with the increase in demand.
A team of BergerABAM engineers has analyzed the current state of design and construction challenges and has developed an all-concrete LNG storage tank solution that has the potential to address these challenges. The concept has been recently published as a paper in the Precast Concrete Institute (PCI) Journal and discusses the work done to develop and qualify the composite cryogenic LNG storage tank technology, showing that a composite concrete cryogenic LNG storage tank offers a more cost-effective, high-quality, and reliable alternative than the steel and concrete tanks currently being used.
The article researched and written by Kåre Hjorteset, PE, SE; Markus Wernli, PhD, PE; Michael W. LaNier, PE; Kimberly A. Hoyle; and William H. Oliver, PE, is available for review in PCI Journal’s Fall 2013 issue.
Cutaway section at the base of a composite concrete cryogenic LNG storage system.
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Precast, Prestressed Concretefor Liquefied Natural Gas Storage Tanks
When the PCI Research and Development Committee sent out a request for research proposals to investigate the behavior of and reinforcement requirements for slender spandrel beams, the then engineering undergraduate student Catrina Walter was selected to be part of the North Carolina State University
(NC State) team. This team consisted of local university researchers and students, as well as industry-respected professional engineers and prestigious PCI member industry partners. This highly public PCI-sponsored research project was one that would further Catrina’s knowledge in a much-needed area of engineering and lead to graduate school opportunities. This project also gave her exposure to engineering firms from all over the country, which is how she ended up joining BergerABAM.
Precast, prestressed concrete spandrel beams are commonly found in parking structures. They are used to transfer vertical loads from the parking garage deck to the columns. They are also used as a barrier around the parking structure edges. Since the early 1980s, smaller scale research projects and in-field observations indicated that the typically prescribed closed stirrups in the webs of spandrels beams may not be necessary for slender, non-compact web sections. The purpose of the PCI-funded project in 2006 was to complete a testing program that would provide real-world data in a controlled laboratory setting, showing that spandrel beams of a certain aspect ratio could be reinforced with less congested, open web reinforcement.
As part of this project, 16 full-scale precast spandrel beams were built and then tested to failure. Shortened, full-scale double-tee deck sections were used to load the spandrel ledges, with a system of hydraulic jacks, to simulate typical field conditions. Aside from the research program, an additional extensive analytical study was completed using finite element models that were developed and calibrated by experimental data. The analytical side of the program was used in conjunction with research results to develop new recommendations for the design of slender spandrel beams, using open web reinforcement. In the end, the research team
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Catrina Walter Receives T.Y. Lin Award
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determined that slender spandrels, reinforced with proper open web reinforcement, was a safe and efficient alternative to the traditional closed stirrup approach. The proposed design guidelines allowed for a faster construction sequence in the precast plants, as well as a more cost-effective design.
For Catrina, it was an enjoyable though challenging research project. “Performing this research at the NC State Constructed Facilities Laboratory was a lot of fun,” she said. “I do remember the pace being pretty fast though. Test specimens were brought in from precasters all over. The specimens were hung from large steel columns that were anchored in place to the labs’ strong floor. Full-scale double-tee deck sections were brought in to load the ledges. It was as if we were building a mini parking garage in our lab almost every other week.”
For this effort, and the resulting two papers published in the Spring and Fall 2011 issues of the PCI Journal, Catrina and her team members, Gregory W. Lucier, PhD.; Sam H. Rizkalla, PhD; Paul Z.T. Zia, PhD; and Gary J. Klein, PE, were awarded the T.Y. Lin Award. This award is given by American Society of Civil Engineers (ASCE). Professor T. Y. Lin, an eminent prestressed concrete pioneer, endowed the award to ASCE in 1968 to recognize outstanding engineers and their contributions to the field of prestressed concrete. The award is presented each year to the best paper written or coauthored by members of ASCE in the various publications of ASCE, PCI, and the American Concrete Institute.
Spandrel beam test specimen after failure at the North Carolina State Constructed Facilities Laboratory.
