In this study, the multi-functional fishway with underground passage, sediment block system reflect the fish's ecological characteristics and many kinds of fish up and down easily is proposed. The 3D-analysis of Reinforced Concrete(R/C) Slab and R/C + Steel Concrete(S/C) Slab with rectangular underground passage are carried out by SAP 2000 software program for multi-functional fishway's durability. The Slab analysis results show that the R/C Slab type of the maximum stress is decreased by 33.5 than that of R/C + S/C type(Size:1m x 0.4m, Velocity: 1.6m/sec)and the shortage of shear is 2 than that of R/C + S/C type(Size:1m x 0.4m, Velocity: 1.6m/sec). The stability of R/C + S/C concrete slab with underground passage is more advantageous than that of R/C concrete slab.

In this study, the multi-functional fishway with underground passage, sediment block system reflect the fish's ecological characteristics and many kinds of fish up and down easily is proposed. The 3D-analysis of Reinforced Concrete(R/C) Slab and R/C + Steel Concrete(S/C) Slab with rectangular underground passage are carried out by SAP 2000 software program about multi-functional fishway's durability. The Slab analysis results show that the R/C Slab type of the maximum stress is decreased by 27.8 than that of R/C + S/C type(Size:0.8m x 0.1m, Velocity: 1.6m/sec)and the shortage of shear is 31.9 than that of R/C + S/C type(Size:0.8m x 0.2m, Velocity: 1.6m/sec). The stability of R/C + S/C concrete slab with underground passage is more favorable than that of R/C concrete slab.

In this study, the world's first multi functional fishway is proposed including underground passway, 3D-analysis of slab that load carrying capacity conditions and pectinate and vertical structure by SAP2000 recognized internationally. The structural analysis results are showed comb from than rectangular form of the maximum stress decreased 35.88%, 32.35% reduction in the moment, shear stress decreased 47.36%. Sidewall structural analysis results are showed comb form than the rectangular form of the maximum stress decreased 22.22, 31.88% reduction in the moment, shear stress decreased 43.48%. When we design to alleviate the water pressure of fishway wall, comb shape is more economical design than perpendicular form.