Resonant Column Apparatus and Blender Elements — MOE Lab Tender Details

 Resonant Column Apparatus and Blender Elements for Fluid Mechanics Engineering Lab Equipments

Resonant Column:
Fully automated
Current driven
Available tests:
o Torsion o Flexure
o Damping
Specimen sizes available
o 50 mm x 100 mm
o 70 mm x 140 mm  
o Custom
The Resonant column apparatus is used to excite one end of a confined solid or hollow cylindrical soil specimen.
The specimen is excited in torsion or flexure by means of an electromagnetic drive system.
Once the fundamental resonant frequency is established from measuring the motion of the free end, the velocity of propagating wave and the degree of material damping and derived.
The shear modulus or young’s modulus is then obtained from the derived velocity and density of the sample
RCA used for control and data acquisition of the RCA apparatus.
The software allows testing to occur via a simple, userfriendly interface.
The tests that may be performed using the RCA Software  
o Resonance in torsion o Resonance in flexure
o Damping ratio in flexure and torsion
Technical Specifications:
o Standard cell capable of 1MPa gaseous cell pressure
o Electromagnetic drive system incorporating precision would coils and composite sintered neodymium iron boron “rare-earth” magnets
o Trans-conductance current driven amplifier
o Inner cell for silicon oil  
o Energisation mode of coils is switchable by software to provide torsional and bending  
o Internal LVDT for measurement of simple deformation
o Internally mounted counter-balanced accelerometer
o 1 off trans-conductance current driven drive amplifier
o 1 off high speed 16 bit data acquisition control card with associated RCA control box/ interface panel
o 3 off calibration weights and calibration bars provided of differing stiffness to enable calibration of system to value  
o 1 off computer controlled proportional gas valve to control cell pressure from software o Back Pressure by GDS Standard pressure/volume controller
o Options for environmental temperature chamber and an axial loading actuator and frame
o Standard specimen sizes 50mm x 100mm x 70mm x 140mm
Bender Element System:
S and P Velocity
Dedicated software
2 Million samples/sec
The Bender Element system enables easy measurement of the maximum shear modulus of a soil at small strains in a triaxial cell.
The measurement of soil stiffness at very small strains in the laboratory is difficult due to insufficient resolution and accuracy of load and displacement measuring devices.  
The capability exists to regularly carry out measurements of small strain stiffness in the triaxial apparatus using local Strain transducers.
The Bender elements are bonded to a standard insert. It has 2 advantages ï‚· Elements are manufactured to allow both S and P waves testing to be performed  
The length of the bender element that protrudes in to the soil has been optimized without compromising the power transmitted by or received to the elements.
This allows the equipment to achieve maximum at its tip whilst only protruding into the material by a reasonable distance.
The bender elements systems connects directly in to a master box which in turn connects to a PC running bender elements control software.
Technical Specifications:
o Data  acquisition speed: = 2,000,000 samples/second simultaneous sampling of both source and received signals  
o Resolution of data acquisition: = 16 bit
o Connectivity of control box: = USB
o Available grain ranges for data acquisition: = from x 10 to x500
o Titanium Inserts for reduced weight