In rural road construction, the use of which of the following is preferred for ensuring
environmental sustainability or to reduce carbon footprint?
1. Copper slag
2. Cold mix asphalt technology
3. Geotextiles
4. Hot mix asphalt technology
5. Portland cement
Select the correct answer using the code given below:
Answer:
(a)
Non-traditional
The usage of Copper slag reduces the usage of primary materials as well as reduces the construction depth which in turn reduces energy demand in building. So, (1) is correct. • Cold asphalt mix is produced by mixing unheated mineral aggregate with either emulsified bitumen or foamed bitumen. Unlike hot mix asphalt (HMA), cold asphalt mix does not require any heating of aggregate which makes it economical and relatively pollution-free (no objectionable fumes or odours). So, (2) is correct and (4) is not correct. • Geotextiles reinforces the soil by adding tensile strength to i. It is used as a rapid de watering layer in the roadbed. So, (3) is correct. • Portland cement production needs energy and can impact the environment. So, (5) is not correct. Therefore, the correct answer is (a).