Question

Arch in cement concrete jack flooring is made of __________ cement concrete.

(a) 1:2:4

(b) 1:3:4

(c) 1:2:3

(d) 2:3:4

The question was posed to me in an online quiz.

My enquiry is from Types of Upper Floors topic in section Floors and Flooring of Construction & Building Materials

Answer 1

Right answer is (a) 1:2:4

The explanation is: Arch in cement concrete jack flooring is made of 1:2:4 cement concrete. The arches are supported on the lower flanges of mild steel joists. The method of construction of cement concrete jack floors is comparatively easy.