Ballast refers to coarse gravels used to lay road or railway subgrade. The most widely used ballast is broken rocks, preferably igneous rocks and hard limestones. Ballast has the following characteristics:
Characteristics of ballast stone
1. Weather resistance and high hardness. For example, basalt, quartz stone, diabase and granite.
2. The particle size meets the standard. For example, basalt super ballast shall be no less than 28mm and no more than 58mm; and the standard for first-grade ballast is 25 - 70mm.
3. A sufficiently dense gradation to provide enough force to hold the sleepers in place.
4. Resistance to temperature changes and water erosion.
Applications of ballast stone
Road or railway subgrade
Ballast can be used to build sidewalks and railway track beds, mainly for railway foundation beds. Its structure is to connect two steel rails with fasteners and fix them to sleepers through the rubber insulation pad, and ballast are placed under the sleepers. The function of ballast in road or railway subgrade:
1. Increase the stability of the rail and prevent the track from moving. By covering the sleepers with ballast, the movement of the track can be reduced.
2. Disperse the pressure of the sleepers on the roadbed. Ballast can distribute weight more evenly.
3. Reduce the vibration and noise caused by trains to increase passenger comfort. The ballast, which is relatively "soft" (as opposed to rails and sleepers), can absorb the impact of steel wheels running on steel tracks.
4. Enhance drainage capacity. The rain can be quickly drained through the gap between the stones. If the stones are not paved, the soil under the tracks will be soft and the tracks will sink in rainy days.
5. Easy to maintain. The line can be easily corrected by raising or reducing ballast.
Ballast for buildings industries
Another common use of ballast is to mix it with cement and water to make concrete for foundations, structural beams, heavy-duty flagstones, fence posts, curbs, etc. Advantages of using ballast in buildings:
1. The ballast is hard and durable. It has corresponding requirements of its hardness, anti-wear performance, anti-impact properties, crush resistance, atmospheric corrosion resistance, water seepage performance, stability performance, etc.
2. Strengthen the concrete. Filling ballast in concrete can enhance the adhesion of concrete and improve its performance.
3. Cost-effective. Ballast does not need to be replaced or repaired as frequently as other materials, so its maintenance costs are low.
Specifications of ballast stone
We can use ballast crusher plant to process all sizes of ballast. The density of the stone is 2g per cubic centimeter. Its specifications are as follows:
|Classification and quality of the stone|
|Category Name||Variety name||Particle size
|Gravel||Extra fine gravel||5--10||1400--1500|
|Pebble||Extra fine pebble||5--10||1600--1800|
Note: Gravel is generally crushed with granite, sandstone, quartzite, basalt and so on; Pebble is the collective name for gravel, river light stone and river gravel.Gravel is generally crushed with granite, sandstone, quartzite, basalt and so on; Pebble is the collective name for gravel, river light stone and river gravel.