Measuring Shear Wave Velocity Using MASW Method to Reduce Cost and Time required in Construction Projects

Surface wave method was introduced as a tool to the geotechnical and infrastructure engineering fields in the early 1980?s. The non-invasive seismic method of multi-channel analysis of surface waves (MASW) is often used to map shear wave velocity variation of soil with depth. In an attempt to increase confidence in the interpreted shear wave velocity (Vs) profile as a result of the ambiguity in the analyzed dispersion characteristics, multichannel method is used in this research to characterize a test site on the ground of Veermata Jijabai Technological Institute (VJTI), Matunga, Mumbai. The multichannel analysis of surface waves (MASW) method originated from the traditional seismic exploration approach that employs multiple (twelve or more) receivers placed along a linear survey line. The present paper indicates results from MASW survey at a site along the VJTI college ground, for which the MASW data acquisition involved the use of a 12-channel PASI seismograph and a 12 nos. of 4.5 Hz Vertical geophones spaced at 5 m each and source offset 7m. The seismic source was a Sledge hammer (10 lbs). WinMasw 6.0 standard version software package was used to process and invert the Surface-wave seismic data in addition to generating the one-dimensional depth versus Shear Wave Velocity (Vs) profiles. The average shear wave velocity of the current study area is 228 m/s. The average shear wave velocity for Mumbai city is ranging from 110 to 350 m/s. The results determine benefits of using non-invasive MASW method in construction projects in a cost effective and time efficient manner as compared to Conventional Geotechnical method.