Inversion of rayleigh waves dispersion using quantum-behaved PSO to characterize the embankment of mud flow Dam in Sidoarjo (LUSI)

The characterization of the embankment can be done by constructing the shear wave velocity in subsurface. The investigation of near surface wave velocity using Rayleigh wave dispersion analysis is popular. This method is very fast and effective to construct the vertical wave velocity, but has no unique solution. As a result, the inverse modelling is often trapped in local optimums. Therefore, we used Quantum-behaved PSO to get the best solution (global optimum). Inversion method using Quantum-behaved PSO was performed on synthetic and field measurement data. Field data acquisition was executed at P80-81 using both active and passive surface waves methods. The inversion result of Rayleigh wave dispersion is shear wave velocity structure. Shear wave velocity imaging resulted by this method was used to characterize the embankment of mud flow dam in Sidoarjo (LUSI) and be compared to the resistivity measurement data. The subsurface structure which is constructed from the inversion of Rayleigh wave gives the same result as the resistivity.