Study and comparison of compaction characteristics of coarse grained soils using Ultrasonic waves and new designed Impact hammer

Obtaining physical and mechanical parameters of the soil has always been the primary challenge in the science of soil mechanics. These parameters are mostly obtained in laboratories or by field tests. In the present paper a hammer similar to Schmidt hammer is introduced which can be used to calculate soil parameters by its single impact. Such a novel hammer is termed RH impact hammer. The results of RH test are compared with that of ultrasonic tests. First, using the modified Proctor compaction test introduced in AASHTO standard, the modeling of the materials is done. In the continuation, the materials with known gradation range and based on the quality parameters such as compaction percent and natural and optimum moisture content are directly exposed to pressure waves of ultrasonic device and are simultaneously compact-metered with RH hammer. Without any field or laboratory experiments and only based on velocity and transmission time of waves and also using calibration plots and correlation formulas and base steel specimen. Readings are above 3 of the densities of more than 90% of the soil.