GB/T 24175-2026Test method for the stability of steel slag (English PDF)

4.6 Dial indicator stand and dial indicator The dial indicator has an accuracy of

0.01 mm.

4.7 Constant Temperature Water Bath Minimum dimensions of the water bath. 1100mm (length) × 330mm (width) × 350mm (height), with temperature control above 90°C. The apparatus for measuring water immersion swelling rate is shown in Figure 1.

4.8 Oven Temperature can be controlled at 105°C with an accuracy of no less than 5°C.

4.9 Filter paper Diameter 152mm.

4.10 Scraper

4.11 Pressure Cooker Design pressure. 2.5MPa; Working pressure. 2.0MPa; Working medium. saturated water vapor; Minimum volume. 0.0085m3.

4.12 Test sieves It conforms to the requirements of GB/T 6003.1 and GB/T 6003.2, with sieve aperture sizes of 31.5mm, 26.5mm, 19.0mm, and 16.0mm. 13.2mm, 9.5mm, 4.75mm, 2.36mm, 1.18mm, 0.3mm, 0.075mm.

4.13 Vibrating Screen The vibration frequency is 221 times/min.

4.14 Steamer tray The bottom has a circular sieve with 1.18mm mesh, a diameter of 100mm, a height of 90mm, and a cloth covering the sieve screen.

4.15 Boiling Chamber Boiling chamber that meets the requirements of JC/T 955.

4.16 Crusher Small jaw crusher.

5.2 Sample Preparation

5.2.1 Take 100 kg of representative sample, dry it, and crush it until it all passes through a

31.5 mm square hole sieve for later use.

5.2.2 The crushed sample was passed through apertures of 31.5mm, 26.5mm, 13.2mm, 4.75mm, 2.36mm, 0.3mm, and 0.075mm. For square-hole sieves, place the sieve sleeve on a vibrating sieve machine and vibrate for 10 minutes; remove the sieve sleeve and sieve by hand one by one according to the sieve hole size until a speed of [number] passes per minute is achieved. The amount of sample passing through the sieve is reduced to less than 0.1% of the total sample volume. The passed sample is then added to the next sieve and sieved together with the sample in the next sieve, in this sequential order. Continue until all sieves have been used.

5.2.3 Prepare compacted test specimens according to the actual particle size distribution in the engineering project. If there are no specific requirements, test specimens can be prepared according to the particle size distribution in Table

1.For steel slag samples... If the maximum natural particle size is less than the maximum particle size in the first column of Table 1, prepare the sample according to the particle size distribution of the maximum particle size in the second column, and so on.

5.3 Test Procedure

5.3.1 Conduct a heavy compaction test according to the compaction test method in GB/T 50123 to determine the optimum moisture content and maximum dry density.

5.3.2 Weigh out 3 portions of steel slag, each weighing 7 kg, according to the particle size distribution requirements in Table

1.Add water at the optimum moisture content, mix thoroughly, and prepare 3 batches of steel slag. The sample was placed in a sealed container.

5.3.3 Place a spacer block inside the mold, cover it with filter paper, and perform heavy compaction molding according to the compaction test method in GB/T 50123.After compaction... After completion, remove the sleeve, scrape off excess steel slag with a ruler and scraper, fill and level the surface of the specimen with fine material, lay filter paper on top, and cover with the porous base. Place the mold... Invert the mold along with the porous base and remove the pad. Place the filter paper back on, install the porous top plate, and wipe the outside of the mold clean.

5.3.4 Four semi-circular load plates, weighing a total of 5 kg, are placed on the porous top plate. A dial gauge holder and a dial indicator for measuring the water immersion expansion rate are then installed on top of these plates. The dial indicator should be accurately aligned with the center contact and kept vertical.

5.3.5 Place the test mold into a constant temperature water bath, ensuring the mold is completely submerged. Immediately read the initial reading d0 of the dial indicator, accurate to [value missing]. 0.01mm.

5.3.6 Water bath heating. After the water bath temperature reaches (80±3)°C, maintain it for 6 hours, then stop heating and allow it to cool naturally. Repeat this process daily as described on day 1. The procedure was followed, and the dial gauge reading was recorded before each daily temperature increase, continuing for 10 days.

5.3.7 Read the final reading d10 of the dial gauge after 10 days.

6.2.1 Take 10 kg of steel slag with a particle size greater than

4.75 mm. Crush the slag sample until it all passes through a

9.5 mm square mesh sieve for later use. Place in an oven and dry at (105±5)°C, then cool to room temperature.

6.2.2 Pour the sample onto a 4.75mm sieve, place the sieve on a vibrating sieve machine, and vibrate for 20 minutes; then remove it and sieve by hand until the sample passes through at a speed of The excess should be less than 0.1% of the total sample volume.

6.2.3 Weigh approximately 800g of steel slag with a diameter of 4.75mm to 9.5mm from the prepared slag sample and prepare 3 slag samples.

6.2.4 If the natural particle size of the slag sample is less than

4.75 mm, then weigh 800 g of steel slag with a natural particle size of

2.36 mm and prepare... Three lousy samples.

6.3 Test Procedure

6.3.1 Rinse the weighed steel slag particles with water to remove surface dust and impurities, ensuring the slag is completely wetted. Place three wet... The steel slag sample was placed in a pressure steamer and then placed in a pressure steamer. It was steamed for 3 hours at a saturated steam pressure of

2.0 MPa. After cooling, the pressure steamer was removed, and the steamed slag was... The steel slag is carefully removed from the steamer and placed on a tray. Any slag powder adhering to the steamer cloth should be gently shaken off and placed on the tray to avoid loss. Dry until Constant weight, weighed, is recorded as m0, accurate to 1g.

6.3.2 Pass the dried steel slag through a 1.18mm sieve. First, place the sieve on a vibrating screen and vibrate for 20 minutes. Then, shake the sieve by hand until the slag passes through at a speed of The excess should be less than 0.1% of the total sample volume. Weigh the slag passing through the sieve, m1, using a balance, accurate to 0.1g.

7.2 Sample Preparation

7.2.1 Take steel slag with a particle size greater than 4.75mm, dry it in an oven at (105±5)°C, and cool it to room temperature.

7.2.2 Weigh approximately 1500g of steel slag with a diameter greater than 4.75mm from the prepared slag sample. Prepare 3 slag samples.

7.2.3 If the natural particle size of the slag sample is less than

4.75 mm, then weigh 800 g of steel slag with a natural particle size of

2.36 mm or larger. Prepare 3 samples. Trash.

7.3 Test Procedure

7.3.1 Place the steel slag sample in an open container, add water to ensure full contact between the water and the steel slag sample, and then place it in a boiling water bath. On the specimen rack, heat to boiling and maintain boiling for 6 hours. Repeat the operation the next day, boiling for a total of 12 hours.

7.3.2 After cooling, remove the open container, dry the steel slag, and pass it through a 4.75mm sieve (if the natural particle size of the slag sample is less than 4.75mm, pass it through a 2.36mm sieve). Weigh the steel slag that passes through a sieve smaller than 4.75mm (or 2.36mm) using a balance.

7.3.3 Each slag sample can be processed simultaneously or in batches according to the above steps.