Loose Riprap Grade Control Structure Design
The Soil Conservation Service has been using loose riprap grade control structures based on the equal energy concept for several years with mixed success. Previous model studies resulted...
Cofferdam Rip-Rap Protection for the New Esna Barrage
A 1:60 undistorted mobile bed model of the Nile River in the vicinity of Esna Barrage was constructed at the Hydraulics and Sediment Research Institute to test rip-rap protection of the...
Stability Criteria for Revetments
A simplified 'black box' approach is presented for a number of revetment systems for banks and shore protection. The design criteria, based on the physical similarity...
The Influence of Uniformity on Riprap Stability
Studies have shown that size uniformity influences the stability of riprap. The ratio of fractional sizes of the riprap mixture, D60/D10,...
Riprap Stability Results from Large Test Channel
Velocity data from a large test channel were used to determine the distribution of depth-averaged velocity and shear stress on the side slope of both straight and curved channels. From...
Model Study of Side Slope Riprap
Laboratory experiments were conducted in 10-m long channels having 1.5 H : 1 V side slopes protected with a 20.7-mm diameter rock layer 1.5 diameters thick. Four models were tested. In...
Breakwater Choices
Most of the maritime breakwaters built throughout the world are of the rubble mount type, with a protective armor constructed of artificial blocks. Despite the multitude of different shapes...
Scour Protection at the Straight Drop Spillway
Tests were conducted to determine the scour and the effect of tailwater on scour downstream of the straight drop spillway stilling basin. Preliminary results are presented on performance...
Riprap Stability in Channel Bends
A systematic test series is underway in a large test channel to define the stability of riprap on the outer bank of channel bends. A 'practical equilibrium' concept...
Beach Erosion Protection Methods: Case Study of Dar City Tanzania
Coastal Tanzania has been experiencing severe beach erosion. Beach erosion is much felt in coastal cities like Dar es Salaam, Tanga etc. Beach erosion in Dar es Salaam has caused damage...
Rock Armouring to Unconventional Breakwaters: The Design Implications for Rock Durability
This paper identifies the need for quantitative durability testing of rock for use on dynamically stable rock armored slopes. The derivation and use of a suite of engineering tests for...
Hydraulic Performance of Berm Breakwaters
In recent years, the concept of unconventional rubble mound breakwaters, i.e berm breakwaters, has gained much attention among researchers and engineers as an economical method to build...
Toe Scour Protection in Open Channels
Scour at the toe of bank protection works is one of the major causes of failure of these structures. Weighted riprap toes are frequently used to prevent bank protection failure due to...
Riprap Design by Modified Safety Factor Method
The Safety Factor method for designing riprap is based upon straight forward physics combining rock properties and flow characteristics. M.A. Stevens developed the method by summing the...
Design of Riprapped Scour Holes for Flip Bucket and Overfall Spillways
Presented in this paper is a simple method of predicting pre-excavated scour depths and geometry for riprapped basins below flip bucket spillways. The input data needed for establishing...
Ocean Erosion Control for the Private Sector
The paper describes some procedures of design and construction of riprap type protective structures to contain ocean erosion and to provide an end product that both gives protection and...
Coastal Zone Management Practices, Northwest Brittany, France
Over the entire coast of Brittany, three government programs have sponsored over 81. 9 million francs (6 ff equals US1, approx. ) of coastal-related programs since 1968. Projects vary...
Armor Protection for Rubble Mound Breakwaters
A brief summary of past practices in breakwater armor system design is presented. The limitations of current design procedures for rubble mound breakwaters are discussed and improved methods...
Evaluation of and Recommendations for Drop Structures in the Denver Metropolitan Area
In 1982, the Denver Urban Drainage and Flood Control District published interim guidelines for the design of sloped, loose riprap drop structures, as well as vertical wall drop structures...
Riprap Stability on Channel Slide Slopes
The stability of riprap placed on a sloping bank is decreased because one component of gravity tends to displace the rock down the slope. Results of riprap stability tests on sloping banks...
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