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...
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...
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...
Calibration of a Bridge Rating Formula for Overload Permits
This paper proposes a method to calibrate a reliability based load and resistance factor design (LRFD) permit evaluation formulation that will account for the overloaded truck's...
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....
Multiple Presence Reduction Factors for Bridges
This paper reviews the multiple presence reduction factors specified in the AASHTO and Ontario codes, and provides a method by which these factors can be established in relation to volume...
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...
Queensboro Bridge Inspection and Rehabilitation
An in-depth inspection of the Queensboro Bridge revealed deterioration of certain elements on the lower level of the main bridge. These elements include the outer roadway cantilever brackets,...
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...
Structural Systems for Multispan Cable Suspended Bridges
Multispan cable suspended bridges, i. e. , cable-stayed or suspension bridges with a large number of consecutive main spans of equal size, must be carefully designed to become economical...
Development of a Double Tee Structural System for Highway Bridges
The fully precast, prestressed double tee beams are tied together by transverse post-tensioning through simple grout filled V-joints. The system provides for complete transversal continuity...
The Behavior of R/C Pinned Bridge Columns under Lateral Loading
Four one-eighth scale one-way hinge details of the type used in highway bridges were tested to study the effect of combined shear and flexure caused by lateral loads. The aspect ratio...
Development and Use of Stress Laminated Timber Deck Bridges
This presentation provides a brief overview of the concepts, development, research needs, economics and recent use of stress laminated timber bridge decks. Repeated articles on the serious...
Micro=Lam? LVL: A New Alternative for Timber Bridges
Laminated veneer lumber (LVL) provides a unique opportunity to obtain large structural members from ever-smaller trees. It provides the added benefit of high treatability. This paper explains...
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