Static, dynamic, with electric tip and piezocone and dilatometric penetrometic surveys to obtain and study the soil characteristic are carried out with the Pagani TG63/200kN penetrometer.
STATIC (CPTM)
The cone penetration test CPTM (mechanical type with mechanical Begemann tip) essentially consists in the measurement of the penetration resistance due to a standardized dimensions and characteristics mechanical tip, driven into the ground at constant speed.
Elaboration, interpretation and graphical display allows to “catalog and parameterize” the crossed soil with a continuous image. Generally this type of test runs in cohesive soils and medium dense sands..
DYNAMIC PENETROMETER MEDIUM(DPM)
The test consisted to embed in the ground a conical metal tip “to lose” put to the end of a steel rod. The embedding is obtained beating, dropping from a constant height, a given weight hammer (30 kg). The estimation is based on the soil penetration resistance, expressed by the number of N shots required to obtain the infixion for a fixed-length (10 cm).
Generally these tests are performed in reduced access areas (unreachable with a cingulate penetrometer).
FLAT DILATOMETER (DMT)
The test with Flat Dilatometer (DMT), also said Marchetti Dilatometer, consists in vertically inflicting in the ground, through a static thrust, a steel blade to the desired depth, and subsequently expand a circular steel membrane, placed on the blade side, using a pressurized gas (generally nitrogen). The collected data rifer to the entering gas pressure, necessary to expand the membrane in two predetermined deformations. The standard test is ASTM D6635-2001 and its field of use is generally similar to the static test, but it’s more risky in the gravel or well densified soils.
Furthermore
In addition to the penetrometer tests listed above, with penetrometer is possible:
- Take undisturbed samples (Shelby)
- Install piezometers to perform the groundwater monitoring
- Continuous sampling for environmental analysis (Diameter = 25 mm)
DYNAMIC PENETROMETER SUPER-HEAVY (DPSH)
The dynamic penetrometer test consists in inflicting in the ground a conical tip (for consecutive lenght = 20 cm) measuring the number of N shots required. The elaboration, interpretation and graphical display allow to “catalog and parameterize” the crossed soil with a continuous image, which also allow a comparison of the consistence of the crossed soils and a direct correlation with geognostic surveys for statigrafic characterization.
Generally, these types of tests are performed in granular soils (coarse sands and gravels).
ELECTRIC TIP (CPTe) e PIEZOCONE(CPTu)
The piezocone static penetration tests allow to acquire, during the continuous pushing motion, the sizes qc (tip resistance) and fs (lateral friction) every centimeter of depth. In addition, with the placement of a porous filter right after the cone (U2), is measured the pore pressure in the soil during penetration. The measured pore pressure is constituted by the sum of the existing hydrostatic pressure and of the positive or negative pore pressure that are due to compression and/or expansion of the soil as a result of the cone insertion. The choice of the position of the filter immediately above the cone base agrees with the practice of the majority of manufacturers. The CPTu tests differ from the cone penetration tests (CPT), especially for better reading accuracy and sampling rate. During piezocone penetration tests it’s possible to make dissipation testing in order to evaluate the consolidation coefficient.
DILATOMETER TESTS (DMT)
The test with Flat Dilatometer (DMT), also said Marchetti Dilatometer, consists in vertically inflicting in the ground, through a static thrust, a steel blade to the desired depth, and subsequently expand a circular steel membrane, placed on the blade side, using a pressurized gas (generally nitrogen). The collected data rifer to the entering gas pressure, necessary to expand the membrane in two predetermined deformations. The standard test is ASTM D6635-2001 and its field of use is generally similar to the static test, but it’s more risky in the gravel or well densified soils.
PENETROMETRO PAGANI TG63/200kN PENETROMETER(Anno 2015)
The Pagani mod. TG63-200 static/dynamic penetrometer of which is equipped our company is able to performs both static CPT/CPTu and dynamics DPSH penetration tests. During CPT testing it’s able to develop a 200 kN (20 t) infixion thrust. The thrust is ensured by an hydraulic piston actuated by a Briggs&Stratton petrol engine. The contrast is secured by its propellers that anchor it to the ground, which permit to reach a maximum infixion depth of 30-35 meters. The penetrometer can be equipped with a Shelby tube sampler attached to the rotating head, used for sampling undisturbed samples of cohesive silts and soft clays. The tool is mounted on a cingulate truck that allows access even on rough, sloping or with reduced access terrains. The penetrometer, in static mode, can be equipped with Begemann tip and load cell to performing penetrometric static tests CPT, or with electric Pagani piezocone tip for CPTe / CPTu tests.
The measuring instruments are periodically subject to calibration in order to ensure the best service quality.