透水框架结构设计与优化

题 关键词 参赛队号:所选题目:A题“Revetmentfloodscoursurroundedsixsidesofpermeableframe”isanewuseofpatentwhichisownedbytheNorthwestWaterConservancyScienceInstandiswidelyused.Butintheprocessofusingtheframework,itmaybeimpactedbywaterandberolledorshifted.Sotheframeworkcannotachievetheidealeffectwhenbepiledingroup.Aimingattheproblemabove，wemodifydesignstructure’sinsufficientandchangetheactualunreasonablepackingwayinthisarticle.Wedesignanewtypeofpermeableframenamed“hollowcuttingAngleofcubepermeableframe”.Onthepremiseofsatisfyingtherequirementsofflood,theframeworkisbetterthan“Revetmentfloodscoursurroundedsixsidesofpermeableframe”inaspectssuchasstructurestrengthandhookedInthispaper,wefirstlyusingmechanismanalysistoget actualframeworkisabstractedasphysicalexperimentmodel.BasedonDarcy-WeisbachFormula,GeometricGaussiandistributionsimilarily,Manningformulaandsoonwecalculateoutaoptimalsizeofapplicableframework.Secondly,“hollowcuttingAngleofcubepermeableframe”isevaluatedfromvariousanglesbycombiningthetheoryofengineeringmechanicsandwavespectrum.Intheprocessofmodeltesting,wefindoutthedecelerationrateofwaterwhenusingthehollowcuttingAngleofcubepermeableframethrougha2-Dflowmathematicalmodel,.Thecalculationresultshowsthattheframeworkhassimilarpermeabilityeffectasthesixsidesofpermeableframewhichispractical.Finally,intheprocessofthemodificationandimprovement,wefirstlychangetheframebarcross-sectionshapeintoatriangle,whichgreatlyimprovethestructuralstrengthofframe,throughthecalculationofthesecondaxialmomentofarea.Secondly,weincreasethesicklehookcomponentintheconnectedvertexbox,whichincreased theoriginalframework’sconnectiondegree. I 削角空心方块在空气中重量b b 设计波高 Ir 图一削角空心透水方框立体 图二削角空心透水方框俯视 VKVaHbAcdegfa,b,c,d,e,fN 再由物理的因次表达式可得到下面公式[H][A][g]LT2

ab2c3def ae2f debfe d 1e2 fe2c

KV( )e(Hg)f(A) 1VH1 1VH1

1 替水深H。则雷诺数和佛汝德数可以表示为RV1H,F

V2KReFf(A) VHe VH1V2f(R

e,Fr

H2

1-f(R,Fr AH

u 其中C1R16，并且不考虑槽壁阻力，所以谢才公式公式（13）n4u2H3 iFCd i控制体水流中受到的重力GG fFGF CAu2 d定义方框抛投密度 Ai,并且令C'C，所 C' u

hfLu JhL

1hf Lu18

u2

C'1 RKKaaRRH，所以aa aHd面的边长。所以阻力系数C'd

HC'

f(a

Cf(a

Cd 因为阻力系数Cd是无因次数，所以在原型和模型中应保持一致，根据几何正态相

而试验的几何比尺是H60,由公式(27)

f n2f(H) u1R23J1n

u1H23i1n nH23i1u

表2不同水深下的n nH1p H1pH

n2 图 H

n2 所 H

H1n2g0.02630.0052exp(5.722H1H

Cdn Cv1V2d

n2 框架高度a，Hab（b为削角空心方框每个侧面的边长 H

2.8H21 削角空心方框的侧面边长约为W

bKD(S1)3S W该式中给出的削角空心框架稳定重量 框架失稳率与击岸波相似参数及平均波周期T击岸波相似参数（即Iribarren数 tannN

率与波周期及击岸波相似参数的关系图，分析得失稳率n随着击岸波相似参数的增大先增大后减小，某一n值对应的值最大。因击岸参数与波周期成正比变化，所以失符合一定的分布规律的，见图从图6可以看出，在f=0附近，S（f）很小，随着f增大，K=HJ 其中

3～5．5、Iribarren数I=2．5～4 0.49I K r ,Ir r I2r由WlnmpeyWalling—ford水工研究所n

6a'3

a a'1 Ba量系数

1b截面二次轴矩（secondaxialmomentofarea），又称截面惯量，或截面对某一轴的惯性矩，是反映截面的形状与尺寸对弯曲变形影响