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• 31. [Article] Numerical Modeling and Analyses of Steel Bridge Gusset Plate Connections

  Gusset plate connections are commonly used in steel truss bridges to connect individual members together at a node. Many of these bridges are classified as non-load-path-redundant bridges, meaning a failure ...

  Citation × Citation Citation Abstract Copy Title: Numerical Modeling and Analyses of Steel Bridge Gusset Plate Connections Author: Kay, Thomas Sidney Year: 2011 Gusset plate connections are commonly used in steel truss bridges to connect individual members together at a node. Many of these bridges are classified as non-load-path-redundant bridges, meaning a failure of a single truss member or connection could lead to collapse. Current gusset plated design philosophy is based upon experimental work from simplified, small-scale connections which are seldom representative of bridge connections. This makes development of a refined methodology for conducting high-fidelity strength capacity evaluations for existing bridge connections a highly desirable goal. The primary goal of this research effort is to develop an analytical model capable of evaluating gusset plate stresses and ultimate strength limit states. A connection-level gusset connection model was developed in parallel with an experimental testing program at Oregon State University. Data was collected on elastic stress distributions and ultimate buckling capacity. The analytical model compared different bolt modeling techniques on their effectiveness in predicting buckling loads and stress distributions. Analytical tensile capacity was compared to the current bridge gusset plate design equations for block shear. Results from the elastic stress analysis showed no significant differences between the bolt modeling techniques examined, and moderate correlation between analytical and experimental values. Results from the analytical model predicted experimental buckling capacity within 10% for most of the bolt modeling techniques examined. Tensile capacity was within 7% of the calculated tensile nominal capacity for all bolt modeling techniques examined. A preliminary parametric study was conducted to investigate the effects of member flexural stiffness and length on gusset plate buckling capacity, and showed an increase in member length or decrease in member flexural stiffness resulted in diminished gusset plate buckling capacity. Title: Numerical Modeling and Analyses of Steel Bridge Gusset Plate Connections Author: Kay, Thomas Sidney Year: 2011 Gusset plate connections are commonly used in steel truss bridges to connect individual members together at a node. Many of these bridges are classified as non-load-path-redundant bridges, meaning a failure of a single truss member or connection could lead to collapse. Current gusset plated design philosophy is based upon experimental work from simplified, small-scale connections which are seldom representative of bridge connections. This makes development of a refined methodology for conducting high-fidelity strength capacity evaluations for existing bridge connections a highly desirable goal. The primary goal of this research effort is to develop an analytical model capable of evaluating gusset plate stresses and ultimate strength limit states. A connection-level gusset connection model was developed in parallel with an experimental testing program at Oregon State University. Data was collected on elastic stress distributions and ultimate buckling capacity. The analytical model compared different bolt modeling techniques on their effectiveness in predicting buckling loads and stress distributions. Analytical tensile capacity was compared to the current bridge gusset plate design equations for block shear. Results from the elastic stress analysis showed no significant differences between the bolt modeling techniques examined, and moderate correlation between analytical and experimental values. Results from the analytical model predicted experimental buckling capacity within 10% for most of the bolt modeling techniques examined. Tensile capacity was within 7% of the calculated tensile nominal capacity for all bolt modeling techniques examined. A preliminary parametric study was conducted to investigate the effects of member flexural stiffness and length on gusset plate buckling capacity, and showed an increase in member length or decrease in member flexural stiffness resulted in diminished gusset plate buckling capacity. Close

• 32. [Article] Geographic and seasonal variation in photosynthetic efficiency and capacity of Rocky Mountain Douglas-fir, Pseudotsuga menziesii var. glauca

  Net photosynthesis was measured for photosynthetic light efficiency and capacity on two-year-old plants from eight different seed sources in three measurement periods. The measurement periods corresponded ...

  Citation × Citation Citation Abstract Copy Title: Geographic and seasonal variation in photosynthetic efficiency and capacity of Rocky Mountain Douglas-fir, Pseudotsuga menziesii var. glauca Author: Pope, Walter William Net photosynthesis was measured for photosynthetic light efficiency and capacity on two-year-old plants from eight different seed sources in three measurement periods. The measurement periods corresponded to the physiological periods 1) prior to bud swelling, 2) after needle elongation, and 3) predormancy. Measurement period differences in both photosynthetic efficiency and capacity were apparent. The pre-bud swelling period had the lowest capacity and efficiency, the pre-dormancy period had the highest capacity and efficiency, and the intermediate period was between the two other periods in capacity and efficiency. Seven seed sources from regions within the Rocky Mountains and one hybrid of Coastal X Arizona origin represented populations from which seedlings were raised and measured. There were no apparent differences with respect to seed-source photosynthetic capacity. There were seed source related differences in photosynthetic light efficiency. The seedlings from the northern Rocky Mountain seed sources had a greater light efficiency than those from the southern-Rocky Mountains. These differences in photosynthetic light efficiency may be linked to summer drought adaption. The Lambert-Beers law type light intensity correction is promising in achieving a better estimate of photosynthetic light efficiency. This light intensity correction is based on the individual plant's morphology, needle number, needle length and needle area. Stomatal conductance was an important covariable in photosynthetic capacity. The light intensity correction and stomatal conductance accentuated seedling differences. This accentuation is viewed as the plant's adapting to the given set of conditions in the growing environment with physiological responses as well as developmental and/Or morphological responses. Title: Geographic and seasonal variation in photosynthetic efficiency and capacity of Rocky Mountain Douglas-fir, Pseudotsuga menziesii var. glauca Author: Pope, Walter William Net photosynthesis was measured for photosynthetic light efficiency and capacity on two-year-old plants from eight different seed sources in three measurement periods. The measurement periods corresponded to the physiological periods 1) prior to bud swelling, 2) after needle elongation, and 3) predormancy. Measurement period differences in both photosynthetic efficiency and capacity were apparent. The pre-bud swelling period had the lowest capacity and efficiency, the pre-dormancy period had the highest capacity and efficiency, and the intermediate period was between the two other periods in capacity and efficiency. Seven seed sources from regions within the Rocky Mountains and one hybrid of Coastal X Arizona origin represented populations from which seedlings were raised and measured. There were no apparent differences with respect to seed-source photosynthetic capacity. There were seed source related differences in photosynthetic light efficiency. The seedlings from the northern Rocky Mountain seed sources had a greater light efficiency than those from the southern-Rocky Mountains. These differences in photosynthetic light efficiency may be linked to summer drought adaption. The Lambert-Beers law type light intensity correction is promising in achieving a better estimate of photosynthetic light efficiency. This light intensity correction is based on the individual plant's morphology, needle number, needle length and needle area. Stomatal conductance was an important covariable in photosynthetic capacity. The light intensity correction and stomatal conductance accentuated seedling differences. This accentuation is viewed as the plant's adapting to the given set of conditions in the growing environment with physiological responses as well as developmental and/Or morphological responses. Close

• 33. [Article] Institutional capacity building through land and water stewardship integration- an analysis of source water protection in Corvallis, Oregon

  Globally, access to safe, reliable drinking water sources is a major challenge of this generation. Protected sources of drinking water provide communities with a sustainable, vital resource, yet many public ...

  Citation × Citation Citation Abstract Copy Title: Institutional capacity building through land and water stewardship integration- an analysis of source water protection in Corvallis, Oregon Author: Odom, Olivia Globally, access to safe, reliable drinking water sources is a major challenge of this generation. Protected sources of drinking water provide communities with a sustainable, vital resource, yet many public water suppliers lack legal authority over their source water protection (SWP) area, especially in surface water systems. Absence of legal authority and ownership restricts institutional capacity. In the absence of legal authority and land ownership, strong social capacity supplements weak institutional capacity for SWP. Using a case study approach, this paper presents a national experience survey of municipal approaches to increasing institutional capacity for SWP; details SWP programs of two similar municipalities; uses those findings to inform the creation of a SWP plan in Corvallis, Oregon with particular attention paid to the augmentation of institutional capacity by integration with existing environmental stewardship organizations; compares institutional outcomes; and finds that social capacity maximization is a viable approach to SWP. Title: Institutional capacity building through land and water stewardship integration- an analysis of source water protection in Corvallis, Oregon Author: Odom, Olivia Globally, access to safe, reliable drinking water sources is a major challenge of this generation. Protected sources of drinking water provide communities with a sustainable, vital resource, yet many public water suppliers lack legal authority over their source water protection (SWP) area, especially in surface water systems. Absence of legal authority and ownership restricts institutional capacity. In the absence of legal authority and land ownership, strong social capacity supplements weak institutional capacity for SWP. Using a case study approach, this paper presents a national experience survey of municipal approaches to increasing institutional capacity for SWP; details SWP programs of two similar municipalities; uses those findings to inform the creation of a SWP plan in Corvallis, Oregon with particular attention paid to the augmentation of institutional capacity by integration with existing environmental stewardship organizations; compares institutional outcomes; and finds that social capacity maximization is a viable approach to SWP. Close

• 34. [Article] Unsaturated Soils and Foundation Design : Theoretical Considerations for an Effective Stress Framework

  This study presents the theoretical background necessary to model the bearing capacity of shallow and deep foundations in partially saturated soils. The conventional bearing capacity equations for shallow ...

  Citation × Citation Citation Abstract Copy Title: Unsaturated Soils and Foundation Design : Theoretical Considerations for an Effective Stress Framework Author: Baker, Josiah D. This study presents the theoretical background necessary to model the bearing capacity of shallow and deep foundations in partially saturated soils. The conventional bearing capacity equations for shallow and deep foundations and the ?-method for deep foundation side resistance have been modified to include the effects of matric suction and varying water contents according to the effective stress framework. A closed-form solution has been proposed for the bearing capacity equation that modifies the overburden, unit weight, and cohesion terms in the conventional equation. The ?-method has been modified to consider suction stresses along the deep foundation and a reduction in K₀ due to tension cracking near the surface. The modified bearing capacity equation for shallow foundations shows good agreement to load-tests performed in partially saturated soils. Monte Carlo simulations were performed on silt loams, sands, and clays to characterize variance and distribution of bearing capacity. The results show that silts have the largest variance while clays have the smallest variance in predicted bearing capacity. Title: Unsaturated Soils and Foundation Design : Theoretical Considerations for an Effective Stress Framework Author: Baker, Josiah D. This study presents the theoretical background necessary to model the bearing capacity of shallow and deep foundations in partially saturated soils. The conventional bearing capacity equations for shallow and deep foundations and the ?-method for deep foundation side resistance have been modified to include the effects of matric suction and varying water contents according to the effective stress framework. A closed-form solution has been proposed for the bearing capacity equation that modifies the overburden, unit weight, and cohesion terms in the conventional equation. The ?-method has been modified to consider suction stresses along the deep foundation and a reduction in K₀ due to tension cracking near the surface. The modified bearing capacity equation for shallow foundations shows good agreement to load-tests performed in partially saturated soils. Monte Carlo simulations were performed on silt loams, sands, and clays to characterize variance and distribution of bearing capacity. The results show that silts have the largest variance while clays have the smallest variance in predicted bearing capacity. Close

• 35. [Article] Thesis on grazing survey of private lands of Eastern Oregon carrying capacity estimates

  Citation × Citation Citation Abstract Copy Title: Thesis on grazing survey of private lands of Eastern Oregon carrying capacity estimates Author: Hole, C. Douglas Title: Thesis on grazing survey of private lands of Eastern Oregon carrying capacity estimates Author: Hole, C. Douglas Close

• 36. [Article] Carrying capacity studies of cattle range

  Citation × Citation Citation Abstract Copy Title: Carrying capacity studies of cattle range Author: Storm, Earl V. Title: Carrying capacity studies of cattle range Author: Storm, Earl V. Close

• 37. [Article] Analysis of Induced Travel in the 1995 NPTS

  In this paper we estimate the relationship between road capacity and vehicle miles of travel (VMT) from a sample of 12,000 respondents from 48 urban areas in the 1995 Nationwide Personal Transportation ...

  Citation × Citation Citation Abstract Copy Title: Analysis of Induced Travel in the 1995 NPTS Author: Strathman, James G., Dueker, Kenneth, Sanchez, Thomas W., Zhang, Jihong, Riis, Ann-Elizabeth Year: 2000 In this paper we estimate the relationship between road capacity and vehicle miles of travel (VMT) from a sample of 12,000 respondents from 48 urban areas in the 1995 Nationwide Personal Transportation Survey (NPTS). Our approach seeks to account for the effects of residential location, employment location, and commute mode choice in estimating the effect of capacity on VMT. VMT is found to be directly related to road capacity, as well as indirectly related through the influence of road capacity on residential and work place densities. Title: Analysis of Induced Travel in the 1995 NPTS Author: Strathman, James G., Dueker, Kenneth, Sanchez, Thomas W., Zhang, Jihong, Riis, Ann-Elizabeth Year: 2000 In this paper we estimate the relationship between road capacity and vehicle miles of travel (VMT) from a sample of 12,000 respondents from 48 urban areas in the 1995 Nationwide Personal Transportation Survey (NPTS). Our approach seeks to account for the effects of residential location, employment location, and commute mode choice in estimating the effect of capacity on VMT. VMT is found to be directly related to road capacity, as well as indirectly related through the influence of road capacity on residential and work place densities. Close

• 38. [Article] An Analysis of Fishing Capacity in the Western and Central Pacific Ocean Tuna Fishery and Management Implications

  Research Paper

  Citation × Citation Citation Abstract Copy Title: An Analysis of Fishing Capacity in the Western and Central Pacific Ocean Tuna Fishery and Management Implications Author: Reid, Christopher, Clarke, Raymond, Rodwell, Len, Jeon, Yongil Research Paper Title: An Analysis of Fishing Capacity in the Western and Central Pacific Ocean Tuna Fishery and Management Implications Author: Reid, Christopher, Clarke, Raymond, Rodwell, Len, Jeon, Yongil Research Paper Close

• 39. [Article] The FAO International Plan of Action for the Management of Fishing Capacity

  In 1999, the FAO Committee on Fisheries adopted an International Plan of Action for the Management of Fishing Capacity. The paper presents this new international fisheries instrument and discusses the ...

  Citation × Citation Citation Abstract Copy Title: The FAO International Plan of Action for the Management of Fishing Capacity Author: Gréboval, Dominique F. Year: 2001 In 1999, the FAO Committee on Fisheries adopted an International Plan of Action for the Management of Fishing Capacity. The paper presents this new international fisheries instrument and discusses the main issues which would need to be addressed by Nations and regional fisheries organizations worldwide to ensure its implementation. Specific attention is given to measurement aspects, management methods, fleet reduction programmes, high seas fisheries and the need for a comprehensive approach to factors which contribute to overcapacity and unsustainability. The paper concludes that implementation raises important issues that need to be further addressed at national, international and global levels. It also suggests that comprehensive research work on the management of fishing capacity is much needed, especially in relation to the use of alternative policies instruments and management methods. Title: The FAO International Plan of Action for the Management of Fishing Capacity Author: Gréboval, Dominique F. Year: 2001 In 1999, the FAO Committee on Fisheries adopted an International Plan of Action for the Management of Fishing Capacity. The paper presents this new international fisheries instrument and discusses the main issues which would need to be addressed by Nations and regional fisheries organizations worldwide to ensure its implementation. Specific attention is given to measurement aspects, management methods, fleet reduction programmes, high seas fisheries and the need for a comprehensive approach to factors which contribute to overcapacity and unsustainability. The paper concludes that implementation raises important issues that need to be further addressed at national, international and global levels. It also suggests that comprehensive research work on the management of fishing capacity is much needed, especially in relation to the use of alternative policies instruments and management methods. Close

• 40. [Article] U.S. Efforts to Prepare Regular Assessments of Overcapacity in Federally-Managed Commercial Fisheries

  Research Paper

  Citation × Citation Citation Abstract Copy Title: U.S. Efforts to Prepare Regular Assessments of Overcapacity in Federally-Managed Commercial Fisheries Author: Terry, Joseph M. Research Paper Title: U.S. Efforts to Prepare Regular Assessments of Overcapacity in Federally-Managed Commercial Fisheries Author: Terry, Joseph M. Research Paper Close