Marohl M.P.H.,Sargent and Lundy LLC
American Society of Mechanical Engineers, Pressure Vessels and Piping Division (Publication) PVP | Year: 2014
Calculation of pressures in a soil body due to finite loads imposed on the soil surface is a necessary step in the design and analysis of buried commodities. This study compares two commonly-applied numerical methods used to develop the vertical soil pressure profiles applied to buried pipes. The methods compared in this study differ in theory, basis, assumptions, complexity, and results, and therefore the comparison is meaningful. Provided is a comparison between design vertical forces on different sizes of buried pipes at a range of soil depth, determined using an integration of Boussinesq's equation  and the method specified by AASHTO . The Boussinesq equation is defined as a function of location in varying two dimensional soil planes and the integration is performed over the boundary of the pipe as well as the applied soil surface footprint. The soil surface loading considered in this study includes the AASHTO Design Truck and the AASHTO Design Tandem, positioned as required by the AASHTO LRFD code . Recommendations for application of the results is provided based upon the resulting force magnitude calculated and ease of application of the methods. Consideration of the effects of redistribution of loading due to pavements or other rigid surfaces is outside the scope of this study. Copyright © 2014 by ASME.
Devgun J.S.,Sargent and Lundy LLC
Proceedings of the International Conference on Radioactive Waste Management and Environmental Remediation, ICEM | Year: 2013
This paper examines the impact of three recent developments on the commercial nuclear power in the United States. These developments include: Yucca Mountain closure and issues related to SNF; actions in response to Fukushima Diaiichi accident, and; energy economics. All of these have had a significant impact on the commercial nuclear power, its future, as well as the reactor decommissioning scene in the US. Copyright © 2013 by ASME.
Kwon G.,Sargent and Lundy LLC |
Engelhardt M.D.,University of Texas at Austin |
Klingner R.E.,University of Texas at Austin
Journal of Bridge Engineering | Year: 2012
This paper is a continuation of research on strengthening the load-carrying capacity of existing noncomposite bridge girders by postinstalling shear connectors. In this study, finite element models were developed to evaluate the behavior of composite beams retrofitted with postinstalled shear connectors over a wide range of variables with an objective of providing preliminary design recommendations. Variables considered in the parametric studies included beam depth, span length, and shear-connection ratio. The parametric studies showed that current simplified design approaches commonly used for partially composite beams in buildings provide good predictions of the strength and stiffness of partially composite bridge girders strengthened using postinstalled shear connectors. Use of a shear-connection ratio of less than 30% is not recommended to avoid nonductile behavior of the strengthened girder. © 2012 American Society of Civil Engineers.
Koopman A.A.,Ramgen Power Systems |
Bahr D.A.,Sargent and Lundy LLC
Proceedings of the ASME Turbo Expo | Year: 2010
The objective of this paper is to better equip the reader with tools to make relative comparisons between different Carbon Capture and Sequestration (CCS) concepts including various CO2 compressor configurations with more confidence. Methods for analyzing comparative costs for CCS implementation in Coal plants, in terms of Levelized Cost of Electricity (LCOE) and cost per ton CO2 removed or avoided ($/tonCO2) are described. The contribution of compression to LCOE is significant and highly dependent on configuration. Critical inputs required for accurately calculating compressor power and some common errors that significantly impact the results of power consumption can increase the estimated power required by 40%. Sensitivity analyses for critical compressor characteristics are provided. In addition, the impact of energy (heat) integration on the overall economics of the plant can reduce the LCOE penalty. Finally, configuration parameters for systems meeting the national targets of 35% LCOE penalty for CCS costs are explored. Copyright © 2010 by ASME.
Fang S.-J.,Sargent and Lundy LLC
Engineering Journal | Year: 2012
Base plate and anchor rod connections are key structural components. A great majority of anchor rods are designed, placed and installed without pretensioning, usually because the structures are considered to be statically loaded. Applications of pretensioned anchor rods are less common and generally limited to certain industrial facilities. This paper provides a brief overview of the current state of the practice regarding pretensioned anchor rods and reviews selected recent pretensioned anchor rod applications in power industry facilities.