DIRECT SHEAR APPARATUS - TOUCH SCREEN HMI & PLC MODEL - SERVO CONTROLLED WITH PC SOFTWARE-

Compliance Standards

IS:2720(PART XIII),IS:11229, ASTM D3080, BS

Introduction

The test covers the determination of consolidated drained or undrained shear strength of a soil material by direct shear. Normal Load, Strain and shearing force are measured directly during the test. Specimen size 60mm square or round can be tested. The complete system consist of Microprocessor based Touch screen operated and controlled Load Frame, Mould assembly or shear box made of brass with accessories, Shear box housing with two ball strips, specimen cutter with set of weights to give normal stress of 3 kg/cm² through lever.

Salient Features :

1. Password protected operation of touch screen Panel and software
2. Touch Screen operated and controlled for TARE, PARAMETER SETTING, START, STOP,
3. The screen displays load, shear stress, horizontal and vertical displacements,
4. Independent taring and calibration of each Channel
5. Programmable Data Transfer interval
6. Precision loading rate of 0.00001 to 9.99999mm / minute.
7. Rapid approach in forward or reverse direction to `Home`position
8. On line data transfer to PC through RS 485
9. With on line and off line software for analysis and reporting
10. Automatic Data saving on touch of `Save Data`
11. Facility for selection of measurement unit KN, KG

LOAD FRAME :

The Load Frame is silent and rigid to not to transmit any vibration to the sample during the test or cause friction between the loading frame and shear box housing assembly. The floor mounted Load frame consist of loading head driven by Servo / stepper motor with gearbox to ensure continuous variable transmission of speed from 0.00001mm/min to 9.99999 mm/min for both forward and reverse directions. Strain rate will remain constant irrespective of the stress. 2 KN Load cell is used for Load measurement while 2 Nos. 0.001 mm sensitivity LVDT is used for vertical and horizontal measurements. Speed and Displacement limits are controlled by limit switch. The load frame has V-strips on which the

shear box housing rests The lead screw connected to the shear box housing helps application of shear stress.. Suitable for specimen of size 60 x 60 x 25mm square or round.

Normal stress is applied to the specimen by utilizing a weight hanger, a lever arm (amplification ratio 10:1) and a vertical loading yoke. Hanger can receive slotted weights which is amplified by the lever arm and transferred to the specimen by the vertical loading yoke as a normal force up to3 kg/cm²

Parameters are entered through touch sensitive three-channel microprocessor based signal conditioning unit suitable to measure Horizontal load, Horizontal Displacement and Vertical displacement during testing. The system receives the output signal from the sensors i.e. Load cell and Displacement Sensors attached to the apparatus. The data of all three channels of Test can be transferred to computer through RS-485 and can be online monitored.

Working on 220/230 Volts, AC single Phase.

SHEAR BOX AND HOUSING :

It comprises of Shear box assembly, 60 mm square, complete with a U-bracket, guide pins and spacing screws, Made of brass, Gripper assembly consisting of two plain grid plates, two perforated grid plates, one base plate, one loading pad, all made of brass. Two porous stones, each 6 mm thick are also supplied. Shear box housing of brass, complete with two ball roller strips. Specimen cutter and mould extracting tool also supplied along with.

Supplied with software as per below listed features :

1. On-Line Data Acquisition Software
2. On-Line Data Transmission from Signal Conditioning Unit to Computer
3. Off-Line Data Analysis Software that does all the Calculations of Direct Shear Test
4. Has option for manual as well as automatic recording of data
5. Calculates Area, Volume, Bulk density, Dry density, Moisture content etc of the specimen(density and moisture content value to be entered manually)
6. Easy to set up and conduct the test
7. User company/Institute logo and address on welcome screen
8. Password protected login screen
9. Software automatically detects the available Communication Ports (com-ports) to establish RS-485 connection
10. Facility to identify and display true/false com-port connection by green or red lamp indication within the software, Eliminating human error
11. User can enter new party name and address details to save all test specific information for later work.
12. Previously stored party name and address details can also be loaded by browsing directory of stored data.
13. Facility to start or stop the complete instrument from software itself
14. User can control and vary the Motor Speed from the software itself
15. Pause and speed reset during the test
16. Self test diagnostic features
17. Facility to select the specimen type        : Square or circular
18. Facility to select the area correction option  : Yes or No
19. Facility to select the type of sample        : Drain or Undrain
20. Real time graph building during the specific test
21. Can store the data of previous test for future use
22. Four different graph windows on a single screen for a specific test sample (Four different readings for each test - so each reading canbe compared in real time and the last graph displays the overlap of three different readings for easy comparison)
23. Tabulated test data, graphs and all test-specific calculations are provided in real time, allowing the operator to monitor tests in process
24. Automatic calculation of Friction Angle & Cohesion Intercept for Peak & residual values
25. Can export logged readings easily to Excel or PDF file
26. Compatible with most soil & rock direct shear test system
27. An operator can change the background of the software.
28. An operator can also add or remove the specific parameters within the software as per the requirements.

An operator can feed in various input information about the test sample.:

1. Test no
2. Test Material
3. Sample type
4. Test Speed
5. Date & Time
6. Density of test sample,
7. Sample weight,
8. Moisture content,
9. Location of test sample,
10. Area correction option
11. No of tests

Plots following various graphs on software screen:

1.  Horizontal Displacement vs Shear Force
2.  Horizontal Displacement vs Vertical Displacement
3.  Normal stress vs Shear Force
4.  Display maximum value of the Dilation Angle along with C & ø Values

Notes :

1.  Use of suitable servo voltage stabilizer with surge protection is strongly recommended and mandatory requirement. Warranty void in case of non compliance.
2. The Instrument can be operated on 110 V AC single phase. Price on request.
3. We are updating and innovating on continuous basis. Data and Design are subject to change without any notice.
4. Annual on site NABL Calibration and maintenance contract is undertaken by EIE at reasonable cost.