فعالية استخلاص سرعات الموجات القصية من موجات رايلي بتطبيق تقنية التحليل متعدد القنوات للموجات السطحية و علاقتها بعدد من المعاملات الجيوتقنية

Abstract EN

TRACT The application of Multi-Channel Analysis of Surface Waves (MASW) has increased re4cently in seismic geotechnical engineering and environmental fields.

The extraction of Vs from the phase velocity of Rayleigh surface waves using MASW technique is relatively fast, more economic, easier to perform in the field and reduces the number of exploratory wells.

The study showed the significance of using MASW to extract shear wave velocities (Vs) from the phase velocity of Rayleigh surface wave for the near-surface layers to a depth of (30 m) by acquisition, processing and interpreting the MASW data.

Therefore, 1D profiles for the seismic shear wave velocity has been estimated in the study area.

Besides the mathematical relationship between shear wave velocity and several geotechnical parameters: Poisson's ratio (σ), Material index (V), Stress ratio (Si), Concentration Index (Ci), maximum load capacity (qu), Effective Angle of Internal Friction (ø), Shear modulus or Rigidity (μ) are obtained.

The results of this study indicated the presence of three layers of rocks.

The first, the upper layer, corresponds to recent superficial deposits.

The second, the middle one, corresponds mostly to the river deposits composed especially of river terraces and clays while the third, the lower layer, corresponds to the upper part of the Fatha Formation, which is mostly composed of marls.

Also in this study, important relationships were found between the shear wave’s velocity and other geotechnical parameters.

The study therefore recommends using these relationships for future projects as it can be used in engineering geology to obtain preliminary results on soil characters.