Page 47 - CAPE Green Engineering Syllabus 2016.docx_Neat

also gives the building community an eco-efficient cement option enabling them to “go green”.
Premium Plus cement is manufactured to the following Standards: ASTM C 595 TYPE IPEN 197-1: 2000
CEM II/ B-P 42.5 N. Pozzolanic cement is usually known as cement replacement.

4.1.1 Cement replacement

Cement replacement or Pozzolanic admixtures or ‘pozzolans’, contain reactive silica (SiO2), and
sometimes also reactive alumina (Al2O3), which, in the presence of water, react with lime (Ca(OH)2) to
form a gel of calcium silicate hydrate (CSH gel) similar to that produced by the hydration of Portland
cement.

Generally, the pozzolans may be subdivided into natural and by-product materials. The former are
naturally occurring materials, and their processing is usually limited to crushing, grinding and sieving.

Such materials include:

1. Natural pozzolans

(a) Volcanic ashes and lava deposits (for example, volcanic glasses and volcanic
tuffs).

(b) Diatomaceous earth, that is, an earth which is mainly composed of the
silicious skeletons of diatoms deposited from either fresh or sea water.

2. By-product materials including industrial wastes. The most common materials in this
group are:

(a) pulverised fly-ash (PFA); and,

(b) condensed silica fume (CSF).

4.1.2 Some of the benefits of Premium Plus cement include:

1. reduced carbon footprint;

2. decreased permeability;

3. greater durability and longevity;

4. improved workability (ease of use); and,

5. reduced risk of thermal cracking and also facilitates a smoother, harder finish.

4.1.3 The Recommended Applications of Premium Plus cement are:

All general purposes: driveways, pavements and sidewalks, reinforced concrete buildings, bridges,
railway structures, tanks, reservoirs, culverts, water pipes and masonry units.

CXC A36/U2/16 43