Technical Guidelines for the Development of Small Hydropower Plants DESIGN
Part 5: Engineering Layout and Hydraulic Structure
SHP/TG 002-5: 2019
D I S C L A I M E R
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© 2019 UNIDO / INSHP- All rights reserved
Technical Guidelines for the Development of Small Hydropower Plants DESIGN
Part 5: Engineering Layout and Hydraulic Structure
SHP/TG 002-5: 2019
ACKNOWLEDGEMENTS
The technical guidelines (TGs) are the result of a collaborative effort between the United Nations Industrial Development
Organization (UNIDO) and the International Network on Small Hydro Power (INSHP). About 80 international experts and 40
international agencies were involved in the document’s preparation and peer review, and they provided concrete comments
and suggestions to make the TGs professional and applicable.
UNIDO and the INSHP highly appreciate the contributions provided during the development of these guidelines and in
particular those delivered by the following international organizations:
- The Common Market for Eastern and Southern Africa(COMESA)
- The Global Network of Regional Sustainable Energy Centres (GN-SEC), particularly the ECOWAS Centre for Renewable
Energy and Energy Efficiency (ECREEE), the East African Centre for Renewable Energy and Energy Efficiency (EACREEE),
the Pacific Centre for Renewable Energy and Energy Efficiency (PCREEE) and the Caribbean Centre for Renewable Energy
and Energy Efficiency (CCREEE).
The Chinese government has facilitated the finalization of these guidelines and was of great importance to its completion.
The development of these guidelines benefited greatly from the valuable inputs, review and constructive comments as well as
contributions received from Mr. Adnan Ahmed Shawky Atwa, Mr. Adoyi John Ochigbo, Mr. Arun Kumar, Mr. Atul Sarthak, Mr.
Bassey Edet Nkposong, Mr. Bernardo Calzadilla-Sarmiento, Ms. Chang Fangyuan, Mr. Chen Changjun, Ms. Chen Hongying , Mr.
Chen Xiaodong, Ms. Chen Yan, Ms. Chen Yueqing, Ms. Cheng Xialei, Ms. Chileshe Kapaya Matantilo, Ms. Chileshe Mpundu
Kapwepwe, Mr. Deogratias Kamweya, Mr. Dolwin Khan, Mr. Dong Guofeng, Mr. Ejaz Hussain Butt, Ms. Eva Kremere, Ms. Fang
Lin, Mr. Fu Liangliang, Mr. Garaio Donald Gafiye, Mr. Guei Guillaume Fulbert Kouhie, Mr. Guo Chenguang, Mr. Guo Hongyou,
Mr. Harold John Annegam, Ms. Hou ling, Mr. Hu Jianwei, Ms. Hu Xiaobo, Mr. Hu Yunchu, Mr. Huang Haiyang, Mr. Huang
Zhengmin, Ms. Januka Gyawali, Mr. Jiang Songkun, Mr. K. M. Dharesan Unnithan, Mr. Kipyego Cheluget, Mr. Kolade Esan, Mr.
Lamyser Castellanos Rigoberto, Mr. Li Zhiwu, Ms. Li Hui, Mr. Li Xiaoyong, Ms. Li Jingjing, Ms. Li Sa, Mr. Li Zhenggui, Ms. Liang
Hong, Mr. Liang Yong, Mr. Lin Xuxin, Mr. Liu Deyou, Mr. Liu Heng, Mr. Louis Philippe Jacques Tavernier, Ms. Lu Xiaoyan, Mr. Lv
Jianping, Mr. Manuel Mattiat, Mr. Martin Lugmayr, Mr. Mohamedain SeifElnasr, Mr. Mundia Simainga, Mr. Mukayi Musarurwa,
Mr. Olumide TaiwoAlade, Mr. Ou Chuanqi, Ms. Pan Meiting, Mr. Pan Weiping, Mr. Ralf Steffen Kaeser, Mr. Rudolf Hüpfl, Mr. Rui
Jun, Mr. Rao Dayi, Mr. Sandeep Kher, Mr. Sergio Armando Trelles Jasso, Mr. Sindiso Ngwenga, Mr. Sidney Kilmete, Ms. Sitraka
Zarasoa Rakotomahefa, Mr. Shang Zhihong, Mr. Shen Cunke, Mr. Shi Rongqing, Ms. Sanja Komadina, Mr. Tareqemtairah, Mr.
Tokihiko Fujimoto, Mr. Tovoniaina Ramanantsoa Andriampaniry, Mr. Tan Xiangqing, Mr. Tong Leyi, Mr. Wang Xinliang, Mr.
Wang Fuyun, Mr. Wang Baoluo, Mr. Wei Jianghui, Mr. Wu Cong, Ms. Xie Lihua, Mr. Xiong Jie, Ms. Xu Jie, Ms. Xu Xiaoyan, Mr. Xu
Wei, Mr. Yohane Mukabe, Mr. Yan Wenjiao, Mr. Yang Weijun, Ms. Yan Li, Mr. Yao Shenghong, Mr. Zeng Jingnian, Mr. Zhao
Guojun, Mr. Zhang Min, Mr. Zhang Liansheng, Mr. Zhang Zhenzhong, Mr. Zhang Xiaowen, Ms. Zhang Yingnan, Mr. Zheng Liang,
Mr. Mr. Zheng Yu, Mr. Zhou Shuhua, Ms. Zhu Mingjuan.
Further recommendations and suggestions for application for the update would be highly welcome.
TableofContents
Sluice(flapgate) 10 20~50 10~20 50~100
Powerhouse(switchyard) 20~30 50 30~50 100
Waterconveyancestructure 10~20 30~50 10 20~30
Energydissipationand anti-scourstructure
10 / 20 /
4.3 Temporaryhydraulicstructure
where
Δh istheheightdifferencebetweenthewavewallcrestandthenormalreservoirlevelorthecheck floodlevel,inm;
Soil p ressure
Special combination
W +G1( )sinα+Hcosα-U3cosα-Qcosφ-α( )
Qcosφ+β( ) -G2sinβ+U3cosβ ………(6)
Theanti-slipstabilitysafetyfactorK'issolvedinaccordancewithK'=K'1=K'2.
W +G1( )sinα+Hcosα-U3cosα-Qcosφ-α( ) ……(7)
(4) IfthestabilityofblockBCDisconsidered:
Qcosφ+β( ) -G2sinβ+U3cosβ ………(8)
Theanti-slipstabilitysafetyfactorKissolvedinaccordancewithK=K1=K2.
Thepositionswhichareimportantinstructure,endures seriouscoldandaredifficulttooverhaul:
Positions whichendureseriouscoldbuthaveoverhaul conditions; (a)Waterlevelchangingareaofupstreamsurfaceofa
Thepositionswhichenduresrelativelyseriouscold:
gravitydam F250 F200 F150 F150 F50
Thepositionswhichslightlyendurecold:
Underwaterpartorinternalconcreteofthegravitydam F50
Severecoldandcoldregions 0.55 0.45 0.50 0.50 0.65 0.45
Mildregion 0.60 0.50 0.55 0.55 0.65 0.45
i) Iftheambientwateriserosive,cementwithbetteranti-erosionperformanceshallbeselected;
Masonrystone
6.1.5 Damfoundationtreatmentdesign
a) Thedesignofseepagecontrolanddrainageofthedamfoundationshallbebasedontheengi- neeringgeology,hydrogeologicalconditionandgroutingtestdataofthedamfoundation,in combinationwiththereservoirfunctionanddamheightandcomprehensivelyconsidertherela- tionshipbetweentheanti-seepageandthedrainagetodeterminethespecificmeasures.
d) Thedesignshallbeimprovedandrevisedaccordingtothechangesingeologicalconditionsand safetymonitoringinformationrevealedduringtheconstructionperiod.
6.1.6.2 Forslopesrelatedtonewbuildings,onthepremiseofmeetingthelayoutofthebuildings,
block
0~0.21 26~24 24~22 22~19 19~16 16~14
0.21~0.41 28~26 26~25 25~22 22~19 19~17
e) Fortheexposedsurfaceofconcretelessthan28-dayage,insulationmeasuresshallbetaken;
4) take comprehensive measureslikeimproving the concrete grading and adding the admixture.
d) Thefollowingmeasuresmaybetakentolowerthemaximumtemperatureoftheconcreteandto meetthejointgroutingrequirements.
Seismic load
Basic co
m bination
where
2A cushionlayerarea 2B speciallayerarea
3A transitionalarea 3B mainrockfillarea
3C downstreamrockfillarea 3E ripraparea
P rockblockmasonry F faceconcreteslab
Relativedensity / 0.75~0.85 / / /
6.3.7.6 Thethicknessofthetoeslabmaybelessthanthethicknessoftheconnectedfaceslabbut shallnotbelessthan0.3m.
6.3.7.7 Thetoeslabofthesand-gravelfoundationwiththecut-offwallshouldbedividedintoup- streamsectionanddownstreamsection.Thetoeslaboftheupstreamsectionshallbeconstructed afterthecompletionofthecut-offwallandbeforethefirstfillingofthereservoir.
6.3.7.8 Thedownstreamsurfaceofthetoeslabshallbeverticaltothefaceplate;theheightofthe toeslabbeneaththebottomsurfaceofthefaceslabshallnotbelessthan0.9m;itmaybelowered forthelowerdampositionsonbothbanks.
6.3.7.9 Thetoeslabconcreteshallhavehighdurability,anti-permeability,crackresistanceandcon- structionworkability,andtherequirementsshallbesameasthoseofthefaceslab.Thedurabilityin- dicesoftheconcretematerialsmaybeselectedinaccordancewiththerequirementsin6.1.4.4.
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where
Key 1 protectivepier 2 face 3 outrigger 4 rail 5 connectingrod 6 idlerwheel(orfixedwheel) 7 wheelseat 8 buttress 9 servicebridge 10 bottomwaterstop
Figure4 Structureschemeofwheeledhydraulicautomaticflapgatewithconnectingrod
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Key 1 limitingpier 2 face 3 outrigger 4 straightrail 5 guiderail 6 movableblock 7 crownblock 8 wheelseat 9 buttress 10 waterstop
Figure5 Structureschemeofwheeledhydraulicautomaticflapgatewithdoublesupports
c=-0.560 S1
S2=H2×B …………………………(17)
Relativelyhard 1.3~1.1 1.3~1.1
Softrock
7.2.8.14 Ifthesluicechamberisequippedwithtwobulkheadgatesorwithonlyonebulkheadgate,
a) Openintake
4 bulkheadgateslot 5 emergencygateslot
3 bulkheadgateslot 4 emergencygateslot
4 hoistroom 5 emergencygateslot
e) Shaftintake
3 trashrack 4 emergencygateslot
3) Trashretaining:thetrashrackandtrashcleaningplatformshallbearrangedontheleading edgeofthewaterintake,andthetrashshallbecleanedwiththetrashremover.
F istheempiricalcoefficient,take1.3to1.5.
qv=(0.1~0.2)γRB …………………………(27)
4) Incasethesurroundingrocksaresupportedbycombinedboltingandshotcreteliningor steelframesreachingastablestatus,thesurroundingrockpressureactingontheinnercon- creteliningorreinforcedconcreteliningmaybediscountedorignored.
PlasticityindexIp 10~17 7~17 1~17 /
Maximumparticlesizeofthe soilparticles(mm)
Contentofcalichenodule,
8.3.7.5 Thebenchmarkmixproportionofsoilmaterialshouldmeetthefollowingrequirements.
anditsvariationscopeshouldbecontrolledwithin±10%.
b) Themixproportionofthethree-elementmixturemaybelime:totalweightofthesoilandsand =14to19,wherethesoilweightshouldbe30%to60% ofthetotalweightofsoiland sand;withregardtotheclaysoilwithahighliquidlimit,thesoilweightshouldnotbemore than50%ofthetotalweightofsoilandsand. 041
c
b) Thewaterdrainage,pipeditchlayout,drainagemethodanddrainagefacilitiesinthepower- houseareashallbedeterminedaccordingtotheimportanceofpowerhouseofthehydropower station,localclimaticcharacteristics,designrainstormintensity,durationofrainfall,design recurrenceintervalofrainstorms,propertiesofthewatercatchment,topographicalfeatures aswellasotherpossiblecatchments.Thedesignrainfallrecurrenceintervalmaybe3to5years andthedesignrainfalldurationmaybe5min.to15min.
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Table26(continued)
Notes1 Inthetable,aappliestothewaterretainingpowerhouseandbappliestothepowerhouseatthedamtoe andtheriver-sidepowerhouse;
1) Theriverbedpowerhouseshallbegreaterthanzerointhecaseofearthquake;underearth- quakeconditions,theallowabletensilestressshallnotbegreaterthan0.1MPa.
3) Inthestresszoneofthearchdam,thedamheelorotherboundarypartswheretensile stressmayoccur,thecrackmetermayalsobelaidouttomonitorthepossiblecracks orthecombinationsituationoftheconcreteandbedrockinadditiontothestrain
downstreamwaterlevels.
c) 1to2settlementandhorizontaldisplacementobservationsectionsshallbearrangedforthe earthandrockfilldamalongthedamaxis;2to3observationpointsshallbearrangedonthedam crestandthedownstreamdamslopeineachsection.Thedisplacementandsettlementgage
pointsshallbelaidoutattheconnectionbetweentheearthdamandtheconcretestructure,the
positionswiththepipeburiedunderthedamandthepositionwithachangeinthedepthoffill- ing.
c) Groundwatermonitoringincludesmonitoringofthegroundwatertableandpressure,discharge atthedrainagepointsandwaterquality.
d) Themonitoringoftheslopereinforcementstructuresincludesthestress-strainmonitoringof theslide-resistantpile,anti-shearhole,anchoragehole,anchorcableandretainingwall.
e) Specialmonitoringofimportantengineeringslopesincludesthemonitoringofprecipitation,
crustalstress,earthquake,etc.
f) Oneormorerepresentativemonitoringprofilesshouldbesetconsideringthegeologicalanden-
C15 C20 C25 C30 C35 C40 C45 C50 C55 C60
Axial
compressive
strength
fc 7.2 9.6 11.9 14.3 16.7 19.1 21.1 23.1 25.3 27.5
Axialtensile
strength ft 0.91 1.10 1.27 1.43 1.57 1.71 1.80 1.89 1.96 2.04
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11.1.4 Inthedesignofthestructuralmembersoftheconcretestructure,thelong-termstrengthof theconcreteshouldnotbeused.However,thecompressivestrengthattheageof60daysor 90daysmaybeuseduponsufficientevaluationinaccordancewiththetypeofstructure,regionalcli- maticconditionsandtimeofloadtransfer.Theincreaseratiointhecompressivestrengthatdifferent agesoftheconcreteshallbedeterminedthroughtest.Iftestdataisunavailable,theratiomaybe usedwithreferencetoTable33.
NOTE Inthetable,thevalueistheratiowhenthestrengthattheageof28daysisassumedtobe1.0;withregard
tothememberscuredwithsteam,theincreaseinthecompressivestrengthalongwiththeagewillnotbe
considered;inthetable,theinfluencesoftheadmixtureandtheadditiveoftheconcretearenotconsidered
inthevalues;inthetable,thevaluesapplytotheconcretewithaconcretestrengthM30orlower;theratio
ofthecompressivestrengthofconcretewithastrengthgradehigherthanM30shallbedeterminedthrough
testing.
11.1.6 Thedensityoftheconcreteshallbedeterminedbytesting.Ifnotestdataisavailable,the densitymaybetakenas24kN/m3forplaincementconcrete;and25kN/m3forreinforcedcement concrete.
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1
Locationssubjecttoseverefrostanddifficulttotreat (1)Tailwaterpositionofthehydropowerstation,thewater
levelchangingregioninwinterattheinlet/outletofthestor-
agehydropowerstation,thesecondphaseconcreteofthe
gateslot,andtherailfoundation;
(2)Structuralmembersandsecondphaseconcreteinthe
waterlevelchangingregionofthenavigationlocknavigable
inwinterorunnavigableundertheinfluenceofthetailwater
levelofthehydropowerstation;
(3)Overflowsurfaceandsecondphaseconcreteofthespill-
way,thegloryholeorotherwaterconveyancepositions
withflowvelocitygreaterthan25m/s,withfloatingice,
heavysedimentorheavybedload;
(4)Openreinforcedconcretepenstock,flumeandthin-wall
fillinggatewellwithwaterinwinter.
2
treatmentconditions (1)Waterlevelchangingregioninwinterontheupstream
3
structureontheshadowedside;
(2)Channelstructureswithwaterorpronetosnowaccu-
mulationandicingforlongdurationinwinter
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Table38(continued)
4
F200 F150 F100 F100 F50
5 Concreteunderwater,inthesoilandtheinternalconcretein largevolume
Hot-rolledsteelbar
NOTE1 Thediameterdofthehot-rolledsteelbarreferstothenominaldiameter;
Steelstrand
1×2 1×3 1×3I 1×7 (1×7)C
φS
Correction CoefficientKz
A.1.2 Thefetchlength(effectivefetch)shallbedeterminedaccordingtothefollowingconditions.
a) Whenthewaterareaonbothsidesofthewinddirectionisrelativelywide,thelineardistance fromthecalculationpointtotheothersidemaybeused.
b) Whenthereislocalnarrowingalongthewinddirectionandthewidthofthenarrowingpointbis lessthan12timesthecalculatedwavelength,thelengthofthewindzonemaybedefinedas 5timesb,andatthesametime,itisnotlessthanthestraight-linedistancefromthecalculated pointtothenarrowingpoint.
∑icosai (i=0±1±2±3±4±5±6) …………(A.1)
Key 1 prevailingwinddirection
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gTm
isthewaveheighth10% atacumulativefrequencyof10% whengD/v2 0=250to1000.
A.2.3 TherelationshipbetweenwaveheighthPatthecumulativefrequencyofP(%)andthemean weightheightmaybeconvertedwithreferencetoTableA.2.
TableA.2 RatiobetweenwaveheighthPandthemeanwaveheightatthecumulative frequencyofP(%)
H/d P(%) 0.1 1 2 3 4 5 10 13 20 50
0.0
0.1
0.2
0.3
0.4
0.5
HP/H
2.97 2.42 2.23 2.11 2.02 1.95 1.71 1.61 1.43 0.94
2.70 2.26 2.09 2.00 1.92 1.86 1.65 1.56 1.41 0.96
2.46 2.09 1.96 1.88 1.81 1.76 1.59 1.51 1.37 0.98
2.23 1.93 1.82 1.76 1.70 1.66 1.52 1.45 1.34 1.00
2.01 1.78 1.69 1.64 1.60 1.56 1.44 1.39 1.30 1.01
1.80 1.63 1.56 1.52 1.49 1.46 1.37 1.33 1.25 1.01
A.2.4 ThemeanwavelengthLmandthemeanwaveperiodTm maybeconvertedaccordingtothe Formula(A.8).
KV 1.00 1.02 1.08 1.16 1.22 1.25 1.28 1.30
TableA.4 Conversionratioofthecumulativefrequencyoftherun-upKF
H d
F(%) 0.1 1 2 3 4 5 10 13 20 50
<0.1 0.1~0.3 >0.3
R0 1.24 1.45 2.20 2.50
c) When1.25<m<1.5,thecalculatedvaluesofm=1.5andm=1.25maybedeterminedbyinter- polation.
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