Engineering Commons^™

Articulating Concrete Blocks: The Long And Winding Road, J. A. Nadeau

International Symposium on Hydraulic Structures

This paper will provide an overview of Articulating Concrete Blocks (ACB’s) from three perspectives: 1. the Manufacturer, 2. The Engineer and 3. The Researcher and how these independent entities interact with each other and the regulatory community to further the scientific understanding and use of ACB systems. ACB’s, since their development in the late 1970’s, represent a growing choice of design engineers in economically solving their critical erosion prevention problems as well as a variety of other non-hydraulic applications. Typical applications of ACB’s are found in protecting channels and canals, dam spillways and embankments, bridge piers and abutments, river bank …

Visual And Photogrammetric Observations Of An Internal Erosion Failure, T. L. Wahl, R. V. Rinehart, M. J. Klein, J. B. Rittgers

International Symposium on Hydraulic Structures

A 0.91-m (3-ft) high, homogeneous, silty clay embankment was tested to investigate erosion processes occurring during failure by internal erosion. The embankment was constructed in a 3.79-m (12.44-ft) wide test flume equipped with a clear acrylic viewing window at the abutment where failure was initiated. Failure was initiated at mid-height when an embedded 12-mm (½-inch) diameter rebar was removed from the embankment. The test lasted approximately 48 minutes, and during that time the erosion pipe enlarged dramatically. The test was stopped just before the collapse of the soil bridge over the enlarged pipe.

Erosion was visually monitored during the test …

Mouth Of The Columbia River North Jetty Erosion Stabilization, C. C. Humphrey, B. J. Abel, H. R. Moritz

International Symposium on Hydraulic Structures

The mouth of the Columbia River (MCR), located at the river’s confluence with the Pacific Ocean between Oregon and Washington, is a critical regional and national gateway for trade and commerce. The MCR is protected and stabilized by three rubble-mound jetties, all of which are in need of major rehabilitation. In 2014 rehabilitation starting with construction of the North Jetty Lagoon Fill project.

Soon after construction of the North Jetty in 1917, deposition of sand caused the formation of a wide beach along the north side of the jetty, which helped protect much of the north side of the jetty …

Shear Stress Distribution Prediction In Circular Channels Using Tsallis Entropy, H. Bonakdari, Z. Sheikh Khozani

International Symposium on Hydraulic Structures

Detailed knowledge of flow and shear stress distribution in channels is essential in accurately calculating the rates of sediment transport and deposition for geomorphic adjustment. Circular cross sections are usual in sewer channels and the sedimentation of suspended material is a significant matter in such sections. In this study, an analytical model is extended to predict the shear stress distribution in circular channels based Tsallis entropy concept. A new formula for estimating shear stress distribution in circular channels is derived by maximizing the Tsallis entropy subject to mass conservation. The distribution derived from the Tsallis entropy is examined using experimental …

State-Of-The-Practice Review Of Maintenance Closure Structures For Large Spillway Gates, C. M. Johnson, R. T. Indri, F. G. Snider, S. M. Planck, K. F. De Lapp

International Symposium on Hydraulic Structures

Maintenance, remediation, and inspection of large spillway gates are best performed in a dry, dewatered state due to reduced overall cost, worker safety, and improved work quality. Provision for gate dewatering has become a key design consideration for new spillways. Unfortunately, many existing spillways were not originally constructed with gate dewatering capabilities. Therefore, maintenance and inspection work has often been scheduled during planned drawdowns or seasonally low reservoir levels. However, for operators of hydroelectric, flood control, water supply, and multi-purpose dams, artificial drawdowns can significantly impact operations, flood protection, downstream habitat, and revenue generation. Aging gates deteriorate and require significant …

Discharge Correlations For Spillways With Radial Gates, Gerald A. Schohl

International Symposium on Hydraulic Structures

Equations used at the Tennessee Valley Authority (TVA) to compute free and gated (orifice) discharges through spillways with radial gates are presented along with correlations based on TVA model test data for discharge coefficients and submergence factors. The correlations and data may be applicable for estimating discharges through gated spillways that are similar to those at TVA and for which specific model test data are unavailable. Included in this paper, perhaps for the first time in the literature, are correlations and data indicating for given gate opening the headwater at which flow begins the transition from free discharge to gated …

Advanced Gate Operation Strategies In Hec-Ras 5.0, C. R. Goodell

International Symposium on Hydraulic Structures

The Hydrologic Engineering Center’s River Analysis System (HEC-RAS) is designed for computing water surface profiles and inundation maps, but it is also able to handle flow through gated structures using a variety of equation sand techniques. HEC-RAS has a small selection of built-in gate types, representing some of the more common gates that are used for controlling flow at dams and canal structures. Each gate type in HEC-RAS has a set of empirical equations that are used to compute head loss through the structure for a given flow. There are also two operational schemes that can be chosen for gates: …

Designing A Steel Gate Dam Across An Ephemeral River – Tempe Town Lake Dam Design, Stewart S. Vaghti, Dean B. Durkee, Andrew J. Lynch

International Symposium on Hydraulic Structures

After the existing Tempe Town Lake downstream dam failed unexpectedly in 2010, the City of Tempe, AZ, USA was tasked with designing and constructing a replacement dam to maintain their lake, pass flows in the ephemeral Salt River, and deliberately lower to avert flooding. Through an alternatives evaluation process, a hydraulically operated steel gate system was selected from a field of twenty studied alternative configurations to replace the existing rubber bladder system.

The gate design produced eight 32.3 meter (106 foot) long, 6.4 meter (21 foot) tall, and 118,000 kilogram (260,000 pound) steel gates operated by single-acting hydraulic cylinders and …

Hydraulic Structures-The Future Of Design, Thomas North

International Symposium on Hydraulic Structures

The state of the art of design of hydraulic structures is changing rapidly. Although hydraulic structures include a broad spectrum of applications, there is an increasing need for specialization in planning, design, materials, construction, risk and hazard assessment, aging infrastructure, and lifecycle maintenance.

Today’s role of hydraulic structures involves improving water management practices, water quality, and environmental restoration and protection. Hydraulic design has expanded to include water planning as well as improvements in the design, construction, operation, and maintenance of locks, dams, spillways, and outlet works. The challenges affecting planning and design involve understanding the role of government policies, economics, …

Baffle Designs To Facilitate Fish Passage In Box Culverts: A Preliminary Study, H. Chanson, W. Uys

International Symposium on Hydraulic Structures

Waterway culverts and road crossings are very common design in water systems, ranging from rural roads to national highways and urban drainage networks. Engineers and biologists need better, more reliable prediction 'tools' during the design stages to compare the bio-engineering performances of a range of design options. Present expertise in environmental hydraulics of culverts is deficient because of the many empirically-based design guidelines which are sometimes outdated and often inadequate for fish passage. In all the cases, the turbulence of the flowing waters must be optimised efficiently to maximise fish migration. This project focused on the development of simple solutions …

Spillway Rock Scour Analysis - Composite Of Physical & Numerical Modelling, Paradise Dam, Australia, E. J. Lesleighter, E. F.R. Bollaert, B. L. Mcpherson, D. C. Scriven

International Symposium on Hydraulic Structures

A number of problems and solutions of rock scour downstream of spillways have been evaluated using a composite approach, based on the gathering of detailed data from a physical model and utilising those data in a sequence of calibration and application of numerical modelling of the scour. Our paper will describe the application of the Computational Scour Model (CSM - Bollaert, 2002 and subsequent) as the numerical procedure that makes the composite approach a proven methodology for such problems. The paper will focus on a case study application of the procedure based on the experiences of flooding and scour at …

Numerical Investigation Of Usbr Type Iii Stilling Basin Performance Downstream Of Smooth And Stepped Spillways, Daniel Valero, Daniel Bung, Brian M. Crookston, Jorge Matos

International Symposium on Hydraulic Structures

Recent systematic studies on air-water flows have included stepped spillways. However, to date little has been investigated about how the hydraulic conditions on the stepped spillway may affect the design of traditional energy dissipation structures. In this paper, both smooth chute and stepped chute configurations terminating with the USBR type III stilling basin are tested by means of numerical modelling, allowing a qualitative comparison. Unsteady RANS equations have been employed altogether with VOF and RNG k-ε for free surface tracking and turbulence modeling, respectively. Eight different Froude numbers (F) ranging from 3.1 to 9.5 have been analyzed for a type …

Interaction Of Hydraulic Structures With Air, Water, And Rock: The Challenge Of Researchers And Designers, Anton J. Schleiss

International Symposium on Hydraulic Structures

Since the last ten years, financial crisis has strongly impacted the global economy, which was mainly the result of un-controlled financial speculations at the stock markets highlighted by the revelations regarding offshore companies. Fortunately, the field of construction of large infrastructures, such as hydraulic schemes, has been left relatively untouched by this crisis. In order to stimulate their economies, many governments across the world have injected significant sums into sustainable infrastructures development.

Full Proceedings: Hydraulic Structures And Water System Management, International Association For Hydro-Environmental Engineering And Research, United States Society On Dams

International Symposium on Hydraulic Structures

No abstract provided.

Hydraulic Structures And Water System Management-Ishs2016 In Perspective, Brian M. Crookston, Blake Tullis

International Symposium on Hydraulic Structures

Hydraulic structures are vital features in our water infrastructure, as they help meet the diverse and challenging demands of society, including conveyance, flood protection, environmental and ecological impacts, and systems management. Indeed, there are a number of challenges facing engineers today. This 6^th IAHR International Symposium on Hydraulic Structures (ISHS2016) brought together domestic and international expertise from research, practice, and implementation in a forum for knowledge exchange and networking discussion on critical issues related to hydraulic structure research, performance, operations, maintenance, and community implications. It continued the rich tradition of this series by stimulating interest on advancement in the …