Seite - 1168 - in Book of Full Papers - Symposium Hydro Engineering

Table 1 Dam material properties for true model Vp Vs ρ Dam body 3500 2200 2000 Dam tunnel 0 0 1.25 Dam foundation 4500 2700 2550 Water 1500 0 1000 Air/Vacuum 0 0 1.25 (a) Setup 1 (b) Setup 2 Fig. 1 Acquisition setup showing distribution of sources and sensors in the domain. The computational domain has a height of 48m and length of 128m, and it comprises of the dam structure 28m high with a crest and base width of 4.5m and 19m respectively. A 30m by 80m water reservoir, a 10m deep foundation and the surrounding air is also considered. A 2D finite difference scheme on a staggered grid is used to solve the elastic wave equation. The computational domain is truncated using a 2.5m (i.e. 10 grid points) thick Convolutional-PML (C-PML) at both sides and at the bottom of the domain. Owing to the high number of the systems’ global degrees of freedom (i.e. identifying 3 parameters for each node in a domain with 512x192 = 98,304 nodes), an inverse analysis using methods such as particle swarm optimization (PSO) for anomaly identification, as used in [4, 5] would increase the complexity of the 1168