SPT and Rotational Probing
SPT PROBE
It is a process that allows the determination of the geological profile and the load capacity of the different subsoil layers, the collection of samples from these layers, the verification of the water table, the determination of the compactness or consistency of sandy or clayey soils, respectively, and also the determination of eventual rupture lines that may occur in the subsurface.
This is a sedimentary layer investigation technique, i.e. it is not used in sound or fractured rock. By its nature, the drilling employed in this technique ends when an impenetrable level or equipment is reached, generally something around 15 to 20 meters deep.
ROTARY PROBE
Rotary probe is an investigation method that consists in the use of a motor-mechanized set, designed to obtain rocky material samples, continuous and with a cylindrical shape, through drilling action given basically by penetration and rotation forces that, conjugated, act with cutting power. The drilling is performed with a diamond cored core barrel, which is simultaneously rotated and pressed against the soil that is being drilled.
The samples collected are called core samples, which are stored in a wooden or plastic box and transported for laboratory analysis. Through the drilling and the analysis of the cores, it is possible to indicate the type of rock, the degree of alteration, fracturing, coherence, schistosity, recovery percentage, and the rock quality index.
