Kiewit Corporation is an employee-owned Fortune 500 contractor based in Omaha, Nebraska. Privately held, it is one of the largest contractors in the world. Recent projects have included several bridge retrofittings in the San Francisco Bay Area, Interstate H-3 project in Hawaii, and building the world's largest geodesic dome at Henry Doorly Zoo in Omaha. Along with significant mining and off-shore operations, the company also contracts small grading projects for residential or commercial development. Wikipedia.
Mueller D.K.,Moretrench |
McCann J.M.,Moretrench |
Wigg K.E.,Moretrench |
Schmall P.C.,Moretrench |
Bartlett M.L.,Kiewit Construction Co.
North American Tunneling 2010 Proceedings, NAT 2010 | Year: 2010
Ground freezing to assist in horizontal tunneling presents unusual challenges to the ground freezing design-build contractor. Stresses on the frozen ground vary with depth and the strength and water tightness of the interface between the frozen ground and existing structures is critical. For the East Side CSO Tunnel project, in Portland, Oregon a hand-mined tunnel was completed between two existing concrete slurry wall shafts at 42.7 m (140 feet) below ground surface. This paper discusses the design, installation and operation of the ground freezing system, together with QA/QC measures employed to ensure full closure and maintain structural competency of the frozen ground during the tunneling activities. Source
Lehnhoff E.A.,Montana State University |
Miller Z.J.,Montana State University |
Brelsford M.J.,Montana State University |
White S.,Montana State University |
And 2 more authors.
Weed Science | Year: 2013
The environment in which a plant grows (maternal environment) can affect seed viability, germination, and dormancy. We assessed the effects of maternal environment on wild oat seed viability, germination, dormancy, and pathogen infection by collecting and analyzing wild oat seed from above and below a barley canopy at three field sites in Montana. The viability of wild oat seed collected below a crop canopy was consistently less than it was for seed from the overstory but varied among sites and years. Reductions in viability because of relative canopy position ranged from 10% to 30%. Effects of position relative to crop canopy on weed seed germination/dormancy rates varied by site and suggest that the direction and magnitude of the effects of maternal environment on dormancy depend on environmental conditions. These effects may be driven by crop competition or by changes in seed pathogen pressure or both. Seven species each of fungi and bacteria were isolated from wild oat seeds. The only fungi causing reductions in seed viability (15%) was isolated from understory seeds, and several bacteria from both overstory and understory sources reduced seed germination. Results suggest that, in addition to the known weed-suppressive effects of using taller or earlier emerging varieties of crops, such crops can reduce weed spread through effects on weed seed demography because weeds growing beneath the crop canopy produce a reduced amount of viable seed that is less likely to germinate in the following year. Nomenclature: Wild oat, Avena fatua L. AVEFA, barley, Hordeum vulgare L. Source
Beljan P.,Kiewit Construction Co.
North American Tunneling - 2014 Proceedings, NAT 2014 | Year: 2014
The design approach used to build the new Near Detector Hall (NDH) at Fermilab without jeopardizing the integrity of the existing MINOS Hall and MINOS Access Tunnel is discussed. The NDH is separated from the existing access tunnel by a relatively thin pillar that is 9.5 ft wide at its thinnest section. The relatively weak Scales Formation and the thin pillar necessitated some changes by the contractor's designer to the original design proposed by the owner's engineer. The alternative design implemented shorter excavation drifts and use of pre-tensioned rock bolts in the pillar and at selected locations in the existing access tunnel to minimize movements. The competent rock in the floor beneath the pillar played an important role in minimizing the deformation during construction. A comparison between predicted and observed responses for the underground openings is also presented. Source
Cho Y.,University of Nebraska at Omaha |
Kabassi K.,Kiewit Construction Co. |
Pyeon J.-H.,San Jose State University |
Choi K.,Texas A&M University |
And 2 more authors.
Journal of Construction Engineering and Management | Year: 2013
Pavement markings provide guidance to road travelers and, when not properly removed during construction projects, can lead to fatal accidents. Current state guidelines, however, do not specify a level of acceptable damage and there is no reliable inspection tool available other than on-site individual visual inspections. To address these shortcomings, the main objective of this study was to identify effective temporary marking removal methods on pavements in roadway construction zones. Unlike previous studies, this research tested an extensive number of removal methods on both concrete and asphalt pavements, especially including dry-ice blasting and environmentally friendly non-MeCl chemical stripping. The methods were selected based on a nationwide survey and literature review. In addition, an innovative removal inspection method was developed using image-processing technology to accurately measure the visual damage to the pavement. Among the tested removal methods, the new non-MeCl chemical stripping method was most satisfactory in terms of performance quality. This study of pavement marking removal and inspection can help state transportation agencies significantly improve the current temporary marking removal practices and inspection protocols. © 2013 American Society of Civil Engineers. Source
Kang J.,Texas A&M University |
Jain N.,Kiewit Construction Co.
Proceedings of the 28th International Symposium on Automation and Robotics in Construction, ISARC 2011 | Year: 2011
Although many efforts have been exerted to increase safety on construction sites, it has never been easy to run a construction project with zero accidents. Previous research indicated that lessons learned from previous projects could help construction professionals prevent repetitive mistakes, but those lessons are based on individual experience, and therefore it is difficult to document and reuse them. Various Web-based database systems were suggested to better manage this tacit knowledge in construction, but transforming someone's tacit knowledge into value for the next project using these systems is still challenging. Well-designed computer games often offer a number of constructive instructional features especially for young generations who have grown up in an era of computer games. Research in education reports that visual presentation facilitates the human's cognitive process. Would visual representation of tacit knowledge in a computer game help construction professionals acquire tacit knowledge and use it to reduce repetitive accidents on construction sites? In order to figure out whether visual presentation of accident cases in a computer game could improve tacit knowledge acquisition and retention, a prototype Xbox 360 computer game presenting accident scenes using 3D computer models was developed and tested with college students working in the field of construction management. The data collected from the experiment shows that visual representation in a computer game has potential to improve tacit knowledge acquisition and retention. This paper presents how tacit knowledge was represented in the computer game, how the test was implemented, and some findings. Source