The Manual Aggregate Weak Particles Testing Apparatus is designed to determine the content of weak particles in coarse aggregates, crushed stone, and gravel. It evaluates aggregate quality by applying specified loads to individual particles and identifying those that fracture under pressure. The apparatus features simple operation, accurate measurement, and reliable performance, making it suitable for aggregate testing laboratories, construction material inspection, and quality control applications.

Manual Aggregate Weak Particles Testing Apparatus

Model:TD320-1

I. Product Introduction

The Manual Aggregate Weak Particles Testing Apparatus is developed and manufactured by our company based on T0320-2000 "Test Method for Weak Particles in Coarse Aggregates" specified in JTG 3410 Standard Test Methods of Aggregate for Highway Engineering.

Reference Standards: ASTM C142, AASHTO T112.

The apparatus is designed to determine the weak particle content in crushed stone, gravel, and crushed gravel. According to the particle size, a compressive load of 0.15 kN, 0.25 kN, or 0.34 kN is applied to each particle individually. Particles that fracture under the specified load are classified as weak particles and are discarded, while the remaining unbroken particles are weighed to determine the weak particle content.

II. Technical Specifications

Maximum Load: 1000 N

Resolution: 1 N

Power Supply Voltage: 220 V

III.Operating Procedure

1. Prepare the test sample. Weigh 2 kg of the air-dried aggregate sample (m₁). If the maximum particle size exceeds 40 mm, weigh 4 kg. Sieve the sample into the following size fractions:

5 mm – 10 mm, 10 mm – 20 mm, and over 20 mm; or

4.75 mm – 9.5 mm, 9.5 mm – 16 mm, and over 16 mm (using square-hole sieves).

2. Position the apparatus. Place the Manual Aggregate Weak Particles Testing Apparatus on a stable, level surface. Adjust the leveling feet to ensure that the instrument is properly leveled and securely supported.

3. Connect the power supply. Plug the input end of the power adapter into an AC 220 V (or AC 110 V) power outlet. Connect the output plug of the adapter to the socket on the right side of the control box, then switch on the power and verify that the instrument is powered on.

4. Power On: Turn on the power switch. The startup screen will appear briefly, after which the display will automatically change to "0.00", indicating that the instrument is ready for testing. If the display does not show "0.00", press the Zero button to reset it. Begin the test only when the display reads "0.00" and the stability indicator remains steady.

5. Unit Selection: It has two weight units: Newton (KN) and Pound Sterling (1b). Press the "Convert" button, and the " " in the upper right corner of the LCD screen will point to the selected weight unit.

6. Testing: The test can be performed when the LCD screen displays "0.00".

7. Testing Procedure: Place each aggregate particle from each size fraction at the center of the compression platform. Apply the specified load according to the particle size: 0.15 kN, 0.25 kN, or 0.34 kN.

8. Weight Lock Function: Press the Lock button to hold the displayed load value. The reading will remain unchanged for convenient recording. Press the Lock button again to switch between the locked and released modes.

9. Power Off: Turn off the power switch. If the instrument will not be used for an extended period, unplug the power adapter from the power outlet.

10. Result Processing: Particles that fracture under the applied load are classified as weak particles and shall be removed. Weigh the remaining unbroken particles and record their mass (m₂).

11. After the test is completed, the equipment and surrounding debris or waste should be cleaned up to keep the product and working environment clean.

12. Notes: Additional Instructions for the Control Panel

12.1 Overload:

When the applied load exceeds the maximum weighing capacity, the display will show "OF" and a continuous alarm sound will be emitted. In case of overload, immediately remove the weight from the loading platform to prevent damage to the load sensor.

12.2 Zero Setting:

Before the test, place the aggregate sample container (disc) on the loading platform and press the Zero button to reset the display before applying the compression load. After removing the test container, the display may show a negative tare weight value. Press the Zero button again to restore the display to zero.

IV. Calculation

Calculate the weak particle content according to the following formula, with the result accurate to 0.1%.

P=(m1-m1)/m1*100

Where:

P — Weak particle content of coarse aggregate (%);

m₁ — Total mass of particles in each size fraction before testing (g);

m₂ — Total mass of intact particles in each size fraction after testing (g).

Appendix: Other Instruments and Materials Used with This Apparatus

1. TD5000 Electronic Balance

2. TDBZS-5/10/20/4.75/9.5/16 Standard Sieves

3. Enamel Tray: One large-size or medium-size shallow tray

4. 3-inch Brush: One piece