Measurements of Time Lag in Concrete Gravity Dam Foundations
Uplift measurements from eight large concrete gravity dams show that the time lag between an increase in headwater level and a corresponding increase in uplift pressure is insignificant....
An Improved Incremental Economic Dispatch Method for Hydroelectric Generators with Nonconvex Energy Production Cost Curves
The Bureau of Reclamation (Reclamation) has undertaken a program to improve water resource management at its hydroelectric powerplants. One feature of the resource optimization program...
Risk Analysis Applications for Dam Safety
Dam safety modifications are intended either to reduce the likelihood of the adverse consequences of dam failure or the magnitude of adverse consequences. For instance, widening a spillway...
Estimating Uplift in Cracks in Concrete Dams
Results are presented of a three year research program on the modeling of uplift pressures in cracks in concrete gravity dams, and the effectiveness of drains in reducing those pressures....
Uplift Pressures and Strengths for Concrete Gravity Dams
This paper presents an overview of the results of a three year study to compile a database of stability parameters and foundation characteristics for older concrete gravity dams. The database...
Uplift Reduction Using Drains
Uplift in cracks and in rock-concrete interface plays a crucial role in dam stability. Drains can be designed to intersect these cracks to reduce uplift. This paper explains how the effectiveness...
Effects of Uplift on a Gravity Arch Dam
This paper evaluates the behavior of a gravity arch dam when subjected to normal static loads and internal hydrostatic pressure (uplift). The ability to model uplift has become necessary...
Evaluation and Rehabilitation of Clogged Drains at Concrete Gravity Dams
Studies have shown that properly spaced drains of adequate depth provide the principal means of relief from uplift pressures beneath concrete gravity dams. Drains often become encrusted...
Robert Moses Procurement and Model Tests ? A Contractor's Perspective
This paper discusses (1) the need to provide realistic cost/benefit evaluation criteria in turbine bid specifications and (2) the benefits of competitive model testing. Recent procurement...
Fish Bypass System Mathematical Models
Mathematical models for fish diversion systems based on fish behavior in conjunction with diversion system structural and hydraulic properties are developed. Guidance efficiency is described...
Direct Load Cell-Based Weighing Lysimeter System
A low-cost weighing lysimeter system is described which is capable of measuring evapotranspiration with an accuracy of 0.05-0.10 mm. A two-lysimeter system with electronic data logger...
Accuracies of Lysimeter Data Acquisition Systems
Electronic dataloggers are integral parts of most weighing lysimeter systems. Dataloggers supply excitation voltages to lysimeter load cells and measure resulting voltage signals. Resolution...
Research for New Water Table Management Systems
Water table management in the form of controlled-drainage and controlled-drainage/subirrigation is a feasible, yet under-utilized, practice in the Atlantic Coast flatwoods, the Ohio River...
Canal Models and You
Unsteady canal simulation models require serious investments of time and personnel. The reasons for deciding to invest in a model, as well as reasons to not invest, are discussed. Canal...
Source of Atrazine and Desethylatrazine in a River, During Base Flow
A budget of atrazine and desethylatrazine loads was computed for a 116-kilometer reach of the Cedar River in Iowa to determine where these compounds enter the river during base-flow conditions....
Economic Evaluation of Farning Systems to Protect Surface and Ground Water Quality
Two approaches are discussed for evaluating the economic and environmental effects of farming systems designed to protect water quality. The scenario approach evaluates specific farming...
A Review of Sediment-Water Column Process Modeling and Future Applications in Waste Load Allocation
The capabilities of empirical modeling techniques are discussed and three promising mechanistic models to simulate sediment-water interactions are reviewed with respect to their possible...
Evolution of Appropriate Technology
Although appropriate technology has been practiced since the beginning of people on earth, the inventiveness of the 20th century is forcing engineers (and others) to look at the multitude...
Environmental Considerations in Sustainable Development and the Application of Appropriate Technology
A fundamental appropriate technology concept is that technologies, as well as the development process, must be environmentally sound. As stated by the United Nations' World...
Using Social Infrastructure in Support of Appropriate Technology
This paper proposes and argues for an expanded definition of social infrastructure, suggesting that the creation, adoption and maintenance of appropriate technology are dependent upon...
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