Use of the results of deep sounding in the design of pile foundations of buildings

Abstract

It is possible to determine, from the results of deep sounding, the density of sandy soils and the top of the bearing subsoil into which the lower ends of the piles should be sunk, i.e. to accurately determine the length of the piles. Field studies were conducted by a 4-man team of drillers which sank 4-5 sounding points in sandy and clayey soils to a depth of 5-7 m. Deep sounding was also performed at points which varied from 6 to 3 in., the engineering surveys of the 74-m long building site. Recommended calibration tables were used in the processing of the results of the deep sounding. The characteristic properties of the building site are tabulated. On the basis of the data obtained, graphs were plotted with the coordinates, driving depth vs. number of rams per 10 cm of sinking. With the graph of driving the probe, the density of soil structure may be determined by means of density tables. The results of these tests have been confirmed by geological investigations greater confidence is expressed in the data obtained from deep sounding in certain cases.