A study on spt-vs correlation on ankara subway routes

Shear modulus which should be known in earthquake-proof structural design, shear wave velocity is an important parameter like modulus of elasticity in determining the dynamic properties of soil. Shear wave velocity is used in microdistricting studies in Geotechnical Earthquake Engineering, in predicting liquefaction potential, in assesssing earthquake properties and stresses caused by a designed (virtual) earthquake towards surface layers on the main rock, in calculating predominant soil period and soil amplification. In-situ seismic methods which is one of the shear wave measuring methods, don?t require drilling wells. It is, therefore, preferred as an experimental method which offers great superiority from economic viewpoint. On the other hand, due to expense of in-situ seismic experiments compared to other site experiments, they are rather preferred in more important projects. When in-situ seismic experiments prove impossible or limited, the necessity to assess the shear wave velocity is causing to look for relations between shear wave velocity and other experimental results. Many researchers have reviewed the correlations between the results of the shear wave velocity and the standart penetration test applied in the drilling wells in order to specify the distiribution intensity of the coarse grained soils and the consisteny of fine grained soils in-situ. The factors influencing the SPT-N value have been identified to also affect the shear wave velocity. In this study, variation of shear wave velocities obtained by in-situ seismic methods with existing measured SPT-N values in Ankara subway routes has been examined and then the correlations and the meaningfulness of the obtained data has been reviewed. Relations have been improved to be used for practical requirements on guessing the variation of SPT-N values with the shear wave velocity in Ankara soils. Furthermore, such correlations have been compared to the former studies.Key Word : SPT, VELOCITY OF SLIPPING WAVE, GEOTECHNICAL