Thresholds for Gravel and Cobble Motion
Flows necessary to initiate motion of rocks on a lateral bar along the Gunnison River in Black Canyon of the Gunnison National Monument are observed. Gravel and cobbles are painted and...

Effects of Particle Shape on Bedload Transport
The effects of particle shape on bedload transport in gravel-bed streams are examined using a similarity approach and fractional transport analysis for data from Piceance Creek, Colorado,...

A General Theory of Channel Adjustment in High Gradient Streams
The paper presents a theory of channel adjustment in high gradient streams. This theory states that given sufficient energy, stream channels will adjust their dimensions and flow hydraulics...

A Mechanism of Pool Formation and Maintenance in Forest Streams
Laboratory and field investigations illustrate a hydraulic mechanism responsible for the formation and maintenance of pools associated with large, in-channel obstructions in forest streams....

Estimating Local Bed Shear Stress in Large Gravel-Bed Rivers
The local bed shear stress ?o1 cannot be directly measured and is typically estimated using flow observations in various theoretical or empirical...

Coarse Sediment Transport and the Maintenance of Fish Habitat in the Upper Colorado River
An analysis of the relation between discharge and boundary shear stress is presented for an alluvial reach of the Colorado River near Grand Junction, CO. The analysis indicates that the...

Boundary Shear in the Vicinity of River Banks
Some experimental data are presented concerning the distribution of boundary shear stresses in trapezoidal open channels for both inbank and overbank flows. The local shear stresses on...

Determination of Geometry and Stress Distribution of an Optimal Stable Channel
A numerical model which determines the geometry of a threshold channel was recently developed (Diplas and Vigilar, 1992). This is important in the design of irrigation canals, channelization...

Width Adjustment: Relative Dominance in Unstable Alluvial Streams
The mechanisms that control the relative dominance of width adjustment in unstable streams are described. Specifically, the role of the following factors affecting the fluvial environment...

Field Evaluation of the Sediment Transport Model Stream with a Bank Erosion Component
The graded sediment routing and stream bed evolution model STREAM of Borah, Alonso and Prasad was expanded earlier by incorporating a riverbank erosion component of Osman and Thorne. In...

Carpet Flow Analysis
Under very high flow conditions, sediment may be transported either in a suspension or by carpet flow, as defined by Bagnold. This study examines the theoretical conditions for carpet...

Stiffness of Low Rise Reinforced Concrete Shear Walls
This report, Stiffness of Low Rise Reinforced Concrete Shear Walls, was prepared by the Working Group on the Stiffness of Concrete Shear Wall...

Improving Development Characteristics of Reinforcing Bars
Prepared by the Civil Engineering Research Foundation. Sponsored by CERF, This report describes the development and implications of a new concrete...

Building Code Requirements for Masonry Structures (ACI 530-92/ ASCE 5-92/TMS 402-92); Specifications for Masonry Structures (ACI 530.1-92/ ASCE 6-92/TMS 602-92); Commentary on Building Code Requirements for Masonry Structures (ACI 530-92/ ASCE 5-92/TMS 402-92); Commentary on Specifications for Masonry Structures (ACI 530.1-92/ ASCE 6-92/TMS 602-92)
Copublished with American Concrete Institute (ACI) and The Masonry Society (TMS) Building Code Requirements for Masonry Structures,...

Wet Mix Shotcrete Used in Subsea Tunnel Environments
To reject the claim that the use of accelerator in shotcrete reduces the compressive strength with time, lately cored samples were taken from an 18 to 19 years old concrete. A wet mixed...

The Influence of Water Glass on the Technological Parameters of Shotcrete
Shotcrete used in tunneling must follow a clearly defined early strength development in order to comply with stresses from rock deformations and drilling and blasting. Accelerators are...

Shotcrete Tests at the Fish Ecca Tunnel
The Fish-Ecca Tunnel is situated in the Eastern Cape and forms part of the Lower Fish Irrigation Scheme. About 25% of the 5032 m tunnel had to be lined with shotcrete. Between February...

An Identity Chart for Steel Fibers
Improvements in ductility and toughness by adding steel fibers to the shotcrete mix are sufficient to enable steel fibers to be used as replacement for steel mesh reinforcements. Steel...

Steel Fiber Reinforced Shotcrete?For Rock Support and Fire Protection
Rapid development in concrete technology and development of equipment has led to a change from dry hand-operated to wet robot shotcreting in Norway. Shotcrete of more than 100 MPa cube...

Factors Controlling Strong Ground Motion and Their Associated Uncertainties
Of special interest in strong ground motion modeling is a quantification of the degree of influence specific physical parameters have on the computed motions. Associated with the model...

 

 

 

 

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