Stable Riprap Size for Open Channel Flows

Channel stabilization Erosion controlRevetments R:1.prap de(dgn Riprap r:evetment is one of the most vlidely used methods for protecting the boundaries of erodible channels, Determining riprap size is one of the most i.mportant steps in the desIgn proc.;ss.Some of the exIsting methods for riprap sizing use the critical shear stress relations and the logarithmic velocity lavm to determine stable rip rap size.Flume data.used in this invest:!.gation silo'\-, that the use of a constant Shields coefficient in the critical ,,[war stre.ssrelations :I.S not valid for relati.veroughness problems like riprap , the velocity laws are not valid for high relative roughness Another limitation of existlng riprap sizing methods is the lack of variation relative to the effects of gradation.thickness, or shape.Usi.ng flume data, 11 riprap sizing method is developed based on aver.agelocal velocity and deptrL Variation in uniformity is descr:tbed by using d 30 as the (Continued)