Considerations for Sizing Water Delivery Systems
The purpose of a water delivery system is to deliver irrigation water to a farm and its design should be based on meeting the requirements of farm water use. The rate, duration and frequency...
Daily Diversion Forecasting for a Large Irrigation Project
A procedure has been developed and tested to forecast demand-type large irrigation diversions on a daily basis. The model is based on hydrologic concepts as well as irrigation scheduling...
Meixner Functions Model Crop Yield vs. Applied Water
Most crop production functions are reported as linear functions even though everyone knows they are not. The few examples of non linear crop production functions that exist in the literature...
Infiltration as a Dependent Variable in Modeling Furrow Irrigation
Most surface irrigation models assume that infiltration is independent of surface flow hydraulics. However, wetted perimeter has been shown to significantly affect infiltration in furrows....
Steady State Fluid Transport Model for Plants
Knowledge of water potentials throughout the xylem and phloem elements as well as in individual cells is fundamental for understanding effects of water and temperature stress on transport...
Estimating Number and Duration of On-Times for Surge Irrigation
Research shows surge flow can achieve efficient and uniform irrigation on some soils. However, most available information focuses on computerized analysis and modeling for research purposes....
The Inflatable Weir and Its Widespread Employment for Irrigation in Japan
Although introduced in the U. S. in the 1950's for groundwater recharging, the inflatable weir has become established only in Japan, in which case it is used almost entirely...
Runoff Model for Watersheds of Nonhomogeneous Characteristics
A watershed of any configuration, topography, and spatial distribution of cover, soil and channel characteristics is described as a plannar grid. Time-varying precipitation is applied...
Modeling Branching Irrigation Canal Networks
A mathematical model of branching canal network has been developed based on solving the integrated form of Saint Venant equations which describing steady and unsteady, uniform and non-uniform...
Physical Model Verification of a Coastal Discharge
A 1:75 scale physical model of a thermal discharge into a rocky, semi-enclosed bay was verified against extensive field data. The model accurately reproduced the prototype temperature...
Theoretical Flow Model for Drop Structures
A theoretical model based on the momentum equation is reviewed for a trapezoidal weir drop structure operating in a trapezoidal channel. Preliminary qualitative results indicate agreement...
General Design for Modifications to Existing Lower Santa Ana Drop Structures
A model study conducted at the Waterways Experiment Station investigated the possibility of utilizing the existing drop structures of the Santa Ana River. Initial tests on selected existing...
Liberty Restored
The Outstanding Civil Engineering Achievement of 1987 is the restoration of the Statue of Liberty in New York Harbor. The restoration work included many engineering tasks that by themselves...
Redundancy Evaluation of Existing Bridges
The redundancy of an existing bridge can only be correctly assessed by considering the full superstructure as a single entity. Any formulation based on the analysis of bridge components...
LFRD Bridge Design as Viewed by the Designer
The load and resistance factor design (LFRD) design concept has been resisted by some bridge engineers on the grounds that it represents a reduction of the 'factor of safety'...
Evaluation of Corroded Steel Bridges
In the United States there is a large inventory of corroded steel bridges. The evaluation of these existing bridges is difficult when considering all the uncertainties involved in deterioration....
Overview of the Guidelines for T/L Structure Loadings
This section introduces a reliability based design methodology that forms the framework for the loading guidelines. A Load and Resistance Factor Design (LRFD) format is presented for the...
Three Automatically Erected Folding Spans
The U. S. Navy has identified three rapidly erected bridges. Each is capable of spanning 400 feet (120 m) with a 70 ton (63 tonne) live load at mid-span. Each will also fold into a 15...
Design of Steel Transmission Pole Structures
This document has been carefully prepared in an effort to provide an authoritative source of information about effective design and fabrication of steel transmission pole structures. The...
Measures Against Wind-Induced Vibrations of Bridges
The design of very flexible structures, such as long-span steel bridges, are frequently governed by wind-induced vibrations. This paper introduces the present situation of the cable-supported...
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