the Folding Fusegate - Hydroplus

Issue 8 - March 2005Perspectives 2005Hydroplus is very upbeat asit begins the 2005 year, itsenthusiasm fuelled by the 40dam rehabilitation projectsstudied in 2004. Increasedinterest in the system ofFusegates and the effortsmade over the past few yearshave resulted in the signing ofseveral contracts.Terminus dam spillway enlargement in California, inaugurated in June 2004.The National Dam Agency of Algeria,in light of the Beni Amrane projectcompleted in 2003, commissionedHydroplus to heighten the Foum elGueiss dam, near Batna. The Fusegatesfor this project are presently underconstruction.As for Australia, it will soon hold therecord for the tallest Fusegates everbuilt. The Jindabyne flood control contract,which is well under way, has hadan energizing effect on the Hydroplusteam. (See article on p. 4)This year Hydroplus will also participatein bilateral financing development programs,sharing its expertise with localgovernments.At the same time, the team – convincedof the system’s potential – will continueto invest in R&D. In so doing, it can relyon support from major partners forconducting fundamental and appliedresearch.Having achieved ISO 9001 and ISO14001 standards last June, Hydroplusrenews its commitment to quality,environment and safety in 2005. It willfocus on steering its clients to the mostbeneficial solutions and accompanyingthem every step of the way, from thedevelopment of their projects to theircompletion. Hydroplus will strengthenits position as a top-notch partner.INSIDEDiscover a new type of Fusegates:the Folding Fusegate

RESEARCH & DEVELOPMENTInitial realease of Folding FusegatesR&D carried out by Hydroplus in cooperation with the Scientific Reasearch Institute of Energy Structures(NIIES) of Russia has borne fruit, as a new type of Fusegate has just been fine-tuned: the Folding Fusegate.This brand new, patented product functions according to the same principle as the original Fusegatesystem and its operation requires neither external energy nor human intervention.What does it look like?WELLEach element is comprised of 4 separateparts:PIER• the panel, attached to the sill of thedam by a rotating axle.• the mobile chamber, which pivots onan axel anchored to the sill on the downstreamside.UPSTREAMPANELWell WLUpstreamWLDOWNSTREAM• the supporting arm, consisting of twofolding bars. Depending on the panelsize, the arm can be reinforced with anadditional bar.CHAMBERARM• the well, linked to the chamber.How does it work?Well WLUpstreamWLUnder normal operating conditionsThe panel is raised and forms a watertightbarrier. The arm, the two bars ofwhich form almost a 180° angle, rests onthe chamber and supports the panel.The Fusegate is stable and operates likean ungated spillway.In case of a major floodWhen the upstream water level reachesthe inlet shaft level, water enters thewell and causes an uplift pressure to developin the chamber. The mobile chamberthen rotates and pushes against thelower section of the arm. As soon as thearm angle comes to an angle greaterthan 180°, the panel falls down flat.During the floodThe panel stays flat, the chamber is backto its original position and the arm remainsbent.Once the flood is over, a winch or a jackingsystem is used to raise the panel upagain.Well WLUpstreamWL2

Testing the technologyA series of laboratory tests was conductedin Russia with the NIIES. The first modelsof Folding Fusegates were experimentedon a hydraulic model, demonstratingtheir expected reaction according tovarious downstream water levels as wellas their great shock resistance.Full size Folding FusegatesThese more than satisfactory results culminated,in July 2004, with the constructionof steel Folding Fusegates, 1.80 mtall, which were installed at one end ofthe Korobrovskaya dam spillway (Russia).Artificial floods validated their proper operationand an observation campaign isnow underway to study their behaviourin icy conditions.In order to optimise the system, various spillwayconfigurations were studied, includingthe installation of Fusegates between wallsparallel to the current in order to recreate theperformances of a labyrinth.3Folding Fusegates do not replace the Fusegates currently onthe market. They function according to the same principle asthe original version, but their more elaborate design allow for aresponse that is better adapted to projects where the local hydrologyrequires frequent lowering of the Fusegates in order toprotect the structure. With the inception of Folding Fusegates,Hydroplus reconfirmed its commitment to R&D while demonstratingthe potential and adaptability of its process.

JINDABYNE DAM – AUSTRALIASuccessful model tests runsThe challenge involving the tallestFusegates in the world (7.6 m high)continues. The Hydroplus team has finetunedits highly innovative concept,which allows the performance ofconventional labyrinth Fusegates to beoptimised through a configuration that iseven more economical.Tests were conducted last fall in cooperationwith the Sogreah Laboratoryin Grenoble, France. Adjustments weremade using two hydraulic models, builtto scales of 1/20 and 1/45 respectively.The first model measured the stability ofthe Fusegates under normal and downgradedworking conditions, while the secondstudied the hydraulic performanceof the spillway.The results of the tests are verysatisfactory. They highlight the potentialuses of Fusegate technology andcontribute to the progress of HydroplusR&D initiatives.Small (above) and large (right)hydraulic models for Jindabyne Dam.The next project step will consist ofpreparing the construction drawings andenvironmental reports necessary to beginconstruction of the Fusegates in the thirdquarter of 2005.Supported by the FASEP (the FrenchGovernment’s Private Sector Study andAid Fund), Hydroplus, in partnership withSogreah, was commissioned to conducta study to optimise the dams belongingto the Royal Irrigation Department ofThailand.The project, which is scheduled to lastover a 10-month period, will begin inMarch. Engineers will closely examineFASEP – THAILANDSolutions for meetingwater needsthe possibility of raising 10 dams, selectedon the basis of technical feasibilitycriteria and the importance of the demandfor water.In so doing, Hydroplus hopes to find asuitable solution to the increasing needfor water in Thailand.Hydroplus5, cours Ferdinand-de-Lesseps92851 Rueil-Malmaison CedexFranceTel: (+33) 1 47 16 44 34Fax: (+33) 1 47 16 42 12Email: contact@hydroplus.com4