UPSC Civil Services 2020 Prelims General Studies Paper I

Explanation

Some of the most used techniques to [build green roads] are cold mix technology, waste plastic technology, fly ash, steel slag, coir and jute geotextile, a cell filled concrete and panel concrete Hence Statement 1,2 and 3 are correct.

Asphalt is one of the most popular paving materials in the world, but not all asphalt is created and used equally. You have two main options in the asphalt world – cold mix asphalt and hot mix asphalt.

● Cold mix asphalt is the most basic of asphalt types. As the name implies, cold mix asphalt does not require heating for application.

● The biggest advantage of the cold mix technology is that on an average, precious fossil fuels —approximately 1,500 litres of diesel per km. Considering 30,000 km annual road construction, cold mix can save the nation 45 million litres and 145.35 million kg in carbon footprint. Therefore cold mix asphalt technology is less polluting than hot mix asphalt technology. Hence Statement 4 is incorrect.

● Portland Cement is an environmentally polluting option due to high emissions in its manufacturing.