It is used to compact inorganic bonded stabilized materials such as cement-stabilized crushed stone and lime-soil into standard specimens through vibration, so as to conduct various mechanical property tests such as strength and density.

Vibratory Compaction Molding Machine

Model:WJJHB-1

I. Product Overview:

The WJJHB-1 type vibratory compaction molding machine is a specialized piece of equipment designed and manufactured according to the technical specifications for vibration-based specimen molding of semi-rigid base materials in the "Test Procedures for Inorganic Binder Stabilized Materials in Highway Engineering (JTG E51-2009)". It is used to manufacture various specimens of inorganic binder stabilized granules, including cylindrical specimens for testing unconfined compressive strength, strength, indirect tensile strength, and compressive resilient modulus, and beam specimens for testing thermal shrinkage coefficient, drying shrinkage coefficient, flexural strength, and flexural resilient modulus.Meanwhile, the equipment design references European standard EN 13286-2:2010 and American standard ASTM C1176/C1176M-20, making it meet international testing method requirements and suitable for export.

II. Main Technical Specifications

1. Static Pressure: 1900 N (Adjustable)

2. Excitation Force: 6800～6900N (Adjustable)

3. Vibration Frequency: 28～30HZ (Adjustable)

4. Cylindrical Specimen Mold

5. Steel Mold: Inner diameter 152mm, height 170mm, wall thickness 10mm

6. Steel Mold Ring: Inner diameter 152mm, height 50mm, wall thickness 10mm

7. Overall Dimensions: Length × Width × Height 680 × 540 × 1750 (mm)

8. Machine Weight: 550kg

9. Power Supply: AC380V (Three-phase four-wire working neutral wire)

III. Equipment Installation

1. Foundation: This equipment experiences significant impact on the ground during the molding process. Therefore, the foundation must have a vibration resistance of at least 10,000 N. The equipment base should be secured with a 5mm thick hard rubber sheet and anchor bolts.

There should be at least 1 meter of space around the equipment for operation and maintenance.

2. Power Supply: The equipment requires a three-phase four-wire 380V, 4KW power supply. The equipment must be reliably grounded.

3. Equipment Connection: The frequency converter and controller should be installed on a level surface. There are five aviation connectors with different pinholes between the control box, the frequency converter, and the equipment body. These can be connected one-to-one.

IV. Operation and Use

1. Using the Frequency Converter (Note: The frequency converter is set to standard test values before leaving the factory; please do not adjust it yourself.)

When the power switch on the control box panel is turned on, the frequency converter is powered on, and the digital window and LCD screen will display the value. The frequency converter panel is shown in Figure 1.

The frequency displayed on the frequency converter upon startup is the originally set frequency. If no change is needed, press the "FWD" key. The original set frequency will be confirmed.

To change the original set frequency, first press the "△" key. The LCD screen will display "Frequency Setting HZ". Then use the ">>" (shift) key in combination with the "△" (increase) key and the "▽" (decrease) key to reset the desired frequency.

After resetting the frequency, the entire digital display will flash. When the vibration start button is pressed, the frequency converter output is started, and the digital display stops flashing. The displayed number is the compaction vibration frequency.

Note: This equipment requires a frequency of 28-30 Hz. Setting the frequency too low will result in insufficient excitation force. Setting the frequency too high will significantly increase the excitation force, potentially damaging the equipment. Therefore, the inverter's output frequency must be checked before starting the molding process; it should be between 28-30 Hz.

2. "Up" button: Controls the guide mechanism and indenter to rise, providing sufficient space for the test.

3. "Down" button: Controls the guide mechanism and indenter to descend and press into the mold.

4. "Start" button: After the time is set, press "Start" to begin the vibration mechanism and complete the test according to the set values.

5. Emergency Stop Button: In case of an accident during the test, or if adjustments or other unexpected events occur, press the emergency stop button to stop the vibration mechanism. Note that the emergency stop button is a self-locking button. After pressing, if you need to restart work after inspection, you should press the button again to reset it. If the time control instrument fails to operate during this process, it must be restarted or the time must be reset after the set time has been completed.

6. Button Precautions: The up and down buttons are for inching control. During operation, carefully observe the position change of the guide rod to prevent damage to the guide sleeve.

Note: The lifting motor driving the loading and unloading mechanism is three-phase powered. Because the motor wiring phase sequence at the factory may not match the user's three-phase power sequence, the loading and unloading buttons on the control box may sometimes move in the opposite direction to the load head. In this case, with the power off, open the lifting motor's junction box and swap the positions of any two of the three power wires at the junction box terminals. This will make the button and action consistent.

7. Vibration

After confirming that the inverter frequency is within the range of 28-30Hz and that the pressure head and mold are aligned, the vibration button can be started to compact the sample. When the vibration compaction reaches the predetermined stroke, press the stop button to stop the vibration compaction process.

8. Vibration Compaction Time

The timing instrument starts simultaneously with the start of vibration compaction and stops when vibration compaction stops, displaying the total time taken for vibration compaction.

V. Mold Making

1. Material Preparation and Specimen Fabrication

For the preparation of materials and the fabrication of specimens, please refer to the "Precautions and related instructions for the vibration compaction test method of inorganic binder stabilized materials in the 'Test Procedure for Inorganic Binder Stabilized Materials in Highway Engineering' (JTG E51-2009)".

2. Mold setting: Place the mold containing the sample on the base plate of the equipment, adjust its position so that the pressure head can just enter the mold when it descends, and then fix the mold to the base plate with screws.

3. Mold Making

After aligning and fixing the pressure head and mold, press the loading button to lower the tray on the lead screw by approximately 100mm below the load. At this point, the entire load force is applied to the sample material in the mold through the pressure head, and the preparation work is complete.

When starting the compaction vibration, mark the starting position on the scale on the right side of the frame. Then start the compaction vibration. When the predetermined compaction position is reached, press the stop button to complete the molding process.

Note: The entire load lifting range is 150mm. There is a scale on the right side of the frame. The load and pressure head can only move within this range; do not exceed it. Otherwise, the lead screw and limit groove will be damaged.

VI. Sample Preparation

1. Install the indenter according to the required sample shape. Cylindrical sample dimensions: 150mm diameter, 150mm height.

2. Take one portion of sample and spread it evenly in a metal pan. Calculate the amount of water to be added to each portion of sample according to the optimum moisture content determined through a pre-existing compaction standard test. Spray water evenly onto the sample and use a small shovel to thoroughly mix it until homogeneous.

In the formula: Qw—the amount of water to be added to the sample (g)

Qn—the mass of aggregate in the mixture (g) and its original moisture content Wn, i.e., the air-dried moisture content (%)

Qc—the mass of cement or lime in the mixture (g) and its original moisture content Wc (%)

W—the required moisture content of the mixture (%).

3. Add the required binder, such as cement or lime-fly ash, to the impregnated sample and mix thoroughly with a small shovel, trowel, or other tools until homogeneous. For samples containing cement, the following vibration test should be completed within 1 hour of mixing. Samples mixed more than 1 hour after mixing should be discarded (except for lime stabilized and lime-fly ash stabilized samples).

4. Divide the mixed material into four portions using the quartering method. Pour the mixture into the drum one by one, tamping it down with a wooden stick about 2cm in diameter as you pour. After filling the drum with the mixture all at once, level the surface and press it down slightly. Then cover it with a piece of pre-cut plastic sheeting. Place the mold along with the mixture on the steel base plate of the vibratory compaction molding machine, and use pressure plates to fix the mold base plate to the vibratory compaction molding machine base plate.

5. After aligning the vibratory compactor head with the test mold, lower the guide frame to ensure that the vibratory compactor head is in close contact with the mixture inside the steel mold. Check the bolts and related connections on the vibratory compactor to ensure that no items are placed on the machine body.

6. Set the vibration time, turn on the vibration switch to start vibration compaction, and carefully observe whether the vibration reaches the jumping state.

7. Raise the vibratory pressure head. Loosen the bolts on the test mold platen and remove the test mold along with the vibrated mixture. Remove the test mold collar. At this point, the top surface of the vibrated and compacted mixture should be flush with the upper edge of the steel mold.

8. Support the pad at the bottom of the mold, carefully place the mold and the mixture inside into a suitable place, and after letting it stand for a period of time according to the type of mixture, use a demolding device to push the compacted mixture out of the mold. For beam-type specimens, loosen the bolts and carefully remove the side plates, but the specimen must still be placed on the steel pad and cannot be moved until the mixture has gained initial strength.

9. After demolding, the specimens should be immediately wrapped in a thin plastic film and placed in a curing room for curing. The curing conditions are the same as those for the static pressure method in the specification.10. For details on the above specimen preparation methods, please refer to the vibration method for semi-rigid base material specimen molding in the Highway Pavement Design Specification JTG D50—2006 issued by the Ministry of Transport. Test Precautions and Related Instructions

VII. Precautions

1. The equipment must be installed on a foundation capable of withstanding an excitation force of over 10,000 N and secured with anchor bolts.

2. The equipment must be reliably grounded using a dedicated ground wire; a neutral wire cannot be used as a substitute. This equipment must be protected against phase loss operation, otherwise it may be damaged.

3. The frequency setting range of the inverter is 28-30Hz, and it must be confirmed when starting vibration pressure.

4. The vertical travel of the load is 150mm and must not exceed the limit groove range.

5. During vibration compaction, operators must not touch the mechanical parts of the equipment to avoid injury.

6. The electric lifting mechanism is equipped with a spare manual handwheel at the worm gear on the upper end of the frame. This handwheel is for use in case of electric failure. Under normal circumstances, the handwheel should be removed from the rotating mechanism to prevent it from being thrown off and causing injury during high-speed rotation.

7. When using electric lifting, pay attention to the lifting height and stop at an appropriate level. Never lift too high, as this may break the lifting rod.

8. When lowering the electric pressure head, sufficient compaction margin should be allowed. Generally, the pressure head should be lowered by more than 5 cm after pressing down on the sample.

9. Vibration time is crucial in experiments, generally around 45 seconds. Too long or too short a time will result in incomplete compaction.

10. The density of vibratory compaction should be higher than that of the semi-rigid base material. The technical specifications of the vibratory compactor are general guidelines; adjustments may be necessary for different mix proportions and site conditions, such as vibration frequency and static pressure.

11. Correlation of semi-rigid base materials: Numerous testing units nationwide have conducted extensive comparative experiments, but a correlation with Marshall compaction has not yet been found.

12. The vibration force is calibrated to 6800N (at 28H2) at the factory. It is also equipped with two sector-shaped counterweights. These counterweights are installed on the gears. All screws must be tightened during installation, otherwise it may cause danger. When these two counterweights are installed and the upper ends of the continuously adjustable counterweights opposite the shaft are leveled (the two fan-shaped ones form a flat upper end and a rounded lower end), the total vibration force is approximately 10000N (1000KG).