Development of Dynamic Simple Shear Apparatus for Small Strain Dynamic Tests on Unsaturated Granular Soils by Bender Element and Ultrasonic Sensors

Document Type : Original Article


1 M.Sc. of Geotechnical Engineering, Depaertment of Civil Engineering, Sharif University of Technology, Tehran, Iran.

2 Associate Profesor, Department of Civil Engineering, Depaertment of Civil Engineering, Sharif University of Technology, Tehran, Iran.

3 Ph.D. of Geotechnical Engineering, Department of Civil Engineering, Sharif University of Technology, Tehran, Iran.


Shear modulus and confined modulus are important parameters for static and dynamic analysis in geotechnical applications. Cyclic simple shear apparatus had been developed by mounting bender element and ultrasonic sensors to measure continuous shear wave and pressure wave velocities for determination of Gmax and M. For this purpose two new pedestals have been fabricated on which HAE ceramic disc and sensors were mounted. A pressure control panel and a hanging column system have been designed to apply high and low matric suction values with high accuracy. Finally, some tests was conducted to verify the result of device performance and to compare with the theoretical results of unsaturated soils.  


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