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.