8/19/2019 Andre Stephens Range of Theory
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1. Types of cement used in the construction engineering
industry.
Type 1-Ordinary Portland cement.
Type 2-Portland Pozzolana cement Type 3-Rapid
hardening cement
Type 4-Lo heat cement
2. Types of admi!tures and their functions.
". Retarding# This is used to delay the chemical reaction that
ta$es place hen the
concrete starts the setting process.
"". %ir &ntrainment# This can increase the freeze tha
dura'ility of concrete. "t
produces a more or$a'le concrete than non-entrained
concrete hile reducing
'leeding and segregation of fresh concrete.
""". (ater reducing# These are chemical products that hen added
to concrete can
create a desired slump at a loer ater cement ration than hat is
normally desired.
"). %cceleration# This is used to increase the rate of concrete
strength de*elopment or
to reduce concrete setting.
). +hrin$age reducing# This is added to the concrete during
initial mi!ing. This could
reduce early and long term drying shrin$age.
3. The importance of curing concrete and to different
methods.
,uring of concrete is an important acti*ity it increases
the rate of hydration. "f no
ater is added then hydration process ont ta$e place/ the crac$s
and other defects
occur0 so the concrete must cure at least 3- days to get the
reuired strength.
". (ater ,uring# This pre*ents e!cessi*e loss of moisture hen
the concrete is
co*ered ith a layer of ater for a predetermined period of
time.
"". em'rane ,uring
. (hat is a steel frame structure5
% steel frame structure is the creation of a steel
s$eleton made up of *ertical
columns and horizontal 'eams. This s$eleton pro*ides the support
for the roof/ all
and floor.
