Reconstitution of Sand Specimens Using a Rainer System


Civil Engineering, Ferdowsi University of Mashhad (FUM)


Air pluviation is a method of preparing laboratory models to carry out many geotechnical experiments. In this study, a new air pluviation device has been developed by the researchers. For laboratory modeling, it is important to calibrate the device using air pluviation to produce accurate specimens with desirable conditions and relative densities. A series of laboratory tests were conducted to evaluate the performance of the proposed system. The main features of the rainer system used in this study are the selection of two identical diffuser sieves and three series of curtain-type rainer of different diameters at constant reciprocating speed of the device during sand pluviation in the embedded rails. The results show the ability of this method in producing sand specimens for laboratory models in relative densities of 28 to 103%, which can produce sands of uniform conditions of loose to very dense at 1.0 to 4.1 m drop height.  Also, according to the results of the experiments, it can be stated that by reducing the diameter of the rainer curtain, soil density of modes covering in small range. The results also reveal that the use of diffuser sieves can produce specimens of extremely high density. For the purpose of the design, construction and efficiency control of this device proposed in this paper, numerous experiments and studies have been undertaken. It is noteworthy to mention some innovative aspects of this device. The first feature of this device is producing specimen with desirable relative density in a wide range of relative density modes. Another outstanding feature of this device is the horizontal and vertical uniformity of the reconstituted specimen with an error of less than 7%.