Waffle Brown Concrete Slabs
It is a grid of waffle-shaped concrete slabs having a tint of brown.

The concrete color, amount of pores, intensity of dust, junctions, dirt color etc. can be manipulated by the Substance SBSAR file.
 
Split Rib Concrete Blocks
It is a split rib block which is made of concrete. The architectural structure is commonly used to build walls.

The SBSAR files allows users to change the colors of the tiles, change the amount of blocks in both axes, control the edge wear level and bump level, set the amount of dents etc.
Concrete Waffle Slabs
From the grid pattern, we know that they are waffle slabs made of reinforced concrete. They grid pattern allows concrete ribs running in 2 directions perpendicular to each other on its underside.

As it appears in public area, dust and dirt can be found on the surface. Besides, there are imperfection at junctions between slabs.