Cone Penetration Tests

PROSOIL uses state of the art Geomil Piezocones. The test consists of driving a series of push rods connected to a cone at the base, and a friction sleeve surrounding the cone, and driving this assembly in the ground by a static load at a slow, uniform rate, provided from a thrust machine, and measuring continuously, or at selected depth intervals, the penetration resistance of the cone and the local friction resistance on the friction sleeve.

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Pressure - Meter Testing

To date, the pressure-meter test has evolved as part of an international standard procedure to give design parameters directly from within the borehole. The Elasto-meter is the sonde to be used for the borehole lateral load test. Through its use, the measurement can widely be extended covering soft soil layers with comparatively large displacement to the hard soil layers as well as the soft rock, both with small displacement. The caliper-type sensor housed in the sonde makes it feasible to detect the load pressure of the Elasto-meter and the deformation of the borehole diameter. Pressure meter test is mainly intended to measure in situ rock deformability around a borehole drilled in rock masses by applying hydrostatic pressure to the borehole wall. Pressure meter test is a method to investigate rock properties and / or rock conditions based on the relation between cavity pressure and radial displacement of borehole obtained from the loading hydrostatic pressure to the borehole wall with a cylindrical rubber membrane (i.e. measure in situ rock deformability around a borehole drilled in rock masses by applying hydrostatic pressure to the borehole wall). Other than rock deformability, there are some cases where rock properties such as rock strength, bearing capacity, etc. and / or rock conditions, such as rock stress, are estimated.

Phicometer Testing

A new methodology for soil exploration for determining soil parameters. While the pressuremeter test provides direct information about the soil stiffness in terms of the Ménard Modulus and indirect information about the shear strength in terms of the limit pressure (Ménard 1957, Gambin 1995), the phicometer test yields directly the shear strength by means of the phicometer friction angle φi and the phicometer cohesion ci. It represents an economic and efficient instrument with respect to subsoil exploration especially for large-scale explorations like for infrastructure constructions.

Plate Load Test (PLT)

This test is intended to permit the relationship between load and settlement (load-settlement curve) to be determined, the aim being to assess the deformation and strength characteristics of soil and to determine the strain modulus and the modulus of sub grade reaction. In this method, loading is applied by pushing a round plate into the ground by a reaction system and measuring the corresponding settlement.

Light weight Deflectometer

Compaction control within 2 minutes!

Manage and control compaction works and improve the quality of construction.

Determine the bearing capacity and compaction quality of soils and noncohesive subbases now fast, reliable, precise.

Field Vane Shear Test

Characterizing underground in situ Cohesion by rotating a tapered Vane.

Screw Plate Load Testing

This test is intended to permit the relationship between load and settlement (load-settlement curve) to be determined, the aim being to assess the deformation and strength characteristics of soil and to determine the strain modulus and the modulus of sub grade reaction at any desired depth. In this method, loading is applied by pushing a round plate into the ground by a reaction system and measuring the corresponding settlement.

In situ Permeability Test

Soils are permeable (i.e., water may flow through them) because they consist not only of solid particles, but a network of interconnected pores. The degree to which soils are permeable depends on a number of factors, such as soil type, grain size distribution, water content, degree of compaction and stress history. The ability to transmit water is characterized by the coefficient of permeability (or hydraulic conductivity).

Installation of Piezometers (Water Table Monitoring Wells)

Standpipe piezometers are considered to be the simplest and most economical method for monitoring the Water Table level within a pre-drilled borehole. This is done by lowering PVC pipes into the borehole which are sealed on the outside with a betonite-seal. The piezometer is then monitored for long periods of time in order to identify the water table level of the borehole by means of a water level indicator.

BAT Piezometer

With the BAT system the water pressure in the soil can be measured accurately and efficiently. With an additional set of attachments the BAT system also offers the possibility of determining the permeability of the soil surrounding the piezometer tip and collecting accurate groundwater samples. Typically the BAT piezometer consists of a filter tip and a sensor, both installed via a steel gas pipe.

The BAT system measures the absolute pressure which guarantees stability, especially during continuous monitoring. The sensor can also be disconnected at any time to check its proper function and to determine the exact depth of the filter tip.

Block Vibration Test

Forced vertical vibration tests are carried out on concrete blocks of 1m x 1m x 1.5m at a depth of 1.5m below ground level. A mechanical oscillator is mounted on the test block such that it generates purely vertical sinusoidal vibrations. The mechanical oscillator is connected through a flexible shaft with DC motor and speed control unit. Four acceleration pick-ups duly calibrated are mounted on the block such that they sense vertical motion of the block. Choosing a suitable value of angle of setting of eccentric masses, the oscillator is made to run at constant frequency. Out put signals from pick-ups are monitored and recorded using Carrier Frequency Amplifiers (CFA) and Digital Storage Oscilloscope.

Electrical Resistivity Tomography (ERT)

Characterizing underground conditions and locating the presence of any anomaly is a challenging endeavor. Non-invasive geophysical measurement techniques have been successfully developed and used in the recent past to interpret the nature of the subsurface without disturbing it.

Electrical Resistivity Tomography (ERT) for subsurface imaging is one of the promising geophysical technologies for characterizing underground conditions and locating the presence of any anomaly. It provides this by determining the electrical resistivity distribution as a function of depth and distance. Resistivity is an intrinsic property of a material and can be used as a diagnostic tool to predict changes, variations or contrasts in the distribution of subsurface media.

Thermal Resistivity of Soil

Prosoil uses the TLS-100 Thermal Unit using the single probe method. This method employs a heat source inserted into the soil whereby heat energy is applied continuously at a given rate. The thermal properties of the soil can be determined by analyzing the temperature response adjacent to the heat source via a thermal sensor. This method reflects the rate at which heat is conducted away from the probe.

Falling Head Permeability

This test in its simplest form consists of applying a hydraulic pressure in the borehole at the test section, and measuring the rate of flow due to this difference in the hydraulic pressure. This test is usually applicable for superficial deposits of sand. This procedure is also used to check the adequacy of the installed piezometers on site.

Percolation Test

Percolation test is a test to determine the absorption rate of soil . The results of a percolation test are required to properly design a septic system. Percolation test consists of digging one or more holes in the soil of the proposed septic zone to a specified depth, pre soaking the holes by maintaining a high water level in the holes, then running the test by filling the holes to a specific level and timing the drop of the water level as the water percolates into the surrounding soil.

PS Suspension Logging Test (Shear Wave Velocity)

PS Suspension Logging is a recently developed method for measurement of shear wave velocities, shear modulus, Poissons Ratio and Youngs Modulus in boreholes as it has become an imperative requirement to grasp precise knowledge of the underground, especially, the vibration characteristics of the ground as they are an important fundamental data for designing earthquake-proof structures.

In this method, the probe in which the seismic source and the geophone are incorporated in a series serves to exert pressure on the borehole wall via the borehole water; furthermore this innovative system functions to measure the propagation velocities of P wave and S wave by detecting the behavior of the borehole water through the geophone of floating type.

PROSOIL uses the OYO P-S Suspension Logger. The advantage of the PS Suspension logging as compared to the Up-hole and Down-hole systems is that, since both the source and the receiver are within the borehole itself, hence making this system least sensitive as possible to traffic vibration and other noise sources.

Packer (Lugeon) Test for Rock

The concept of this test lies in the measurement of the volume of water that can escape from an uncased section of a borehole in a given time under a given pressure. Flow is confined between known depths by means of packers. The flow is confined between two packers in a double packer, or between one packer and the bottom of a hole in a single packer. In other words this test measures the acceptance of water under pressure by in-situ rock, to determine the permeability and Lugeon value.