Correct Answer - Option 4 : Seeding
Concepts
The addition of a small percentage of finely ground, fully hydrated Portland cement to fresh concrete mix is called seeding. This is done to accelerate the cement hydration.
An admixture is defined as a material other than water, aggregates, cementitious materials, and fiber reinforcement, added in concrete before or during its mixing to modify its freshly mixed, setting, or hardened properties.
Sulphur impregnation means addition of sulphur in small percentage in lean concrete in order to modify its properties. By doing so, the high strength of concrete can be achieved in a very short interval of time. The sulphur infiltrated concrete can be used for the manufacture of precast roofing elements, fencing posts, sewer pipes and railway sleepers.
A reverberation, or reverb, is created when a sound or signal is reflected causing numerous reflections to build up and then decay as the sound is absorbed by the surfaces of objects in the space – which could include furniture and people.
