Steel slag can be the material for which of the following?

1. Construction of base road

2. Improvement of agricultural soil

3. Production of cement

Select the correct answer using the code given below:

The correct answer is 1, 2 and 3.

Steel slag is a byproduct of the steelmaking process, produced during the separation of the molten steel from impurities in steelmaking furnaces. Rather than being discarded as waste, steel slag has several valuable applications across different industries due to its physical and chemical properties.

1. Construction of base road:
Steel slag possesses high mechanical strength, durability, and excellent aggregate interlocking properties. These characteristics make it an ideal material for road construction, particularly for base and sub-base courses, asphalt concrete pavements, and embankments.

2. Improvement of agricultural soil:
Steel slag is rich in essential nutrients and minerals, such as calcium oxide (CaO), magnesium oxide (MgO), silicon dioxide (SiO₂), and iron. Because of its high calcium and magnesium content, it acts as a basic (alkaline) agent. When applied to agricultural soils, it helps neutralize soil acidity (similar to agricultural lime), improves soil structure, and supplies key nutrients to crops.

3. Production of cement:
Due to its chemical composition, which is highly compatible with the raw materials used in cement production, ground granulated steel slag can be used as a raw material in cement kilns or as an additive (active mineral admixture) in Portland cement. Utilizing slag reduces the consumption of natural limestone, lowers energy requirements, and decreases carbon dioxide emissions during cement manufacturing.

Therefore, steel slag can be utilized for all three purposes: construction of base roads, improvement of agricultural soil, and production of cement.