is about study the effect of water cement ratio on workability of concrete , and type
of work has been carried done by lab
experiment in 5th and 6th experiment and
the result was if the mixing of concrete is increases that because W/C
is increase .That mean W/C is increase with
increase in the mixing of concrete . that the slump test is to characterize the
workability of the fresh concrete and the relationship between water cement
ratio and slump of the mix is positive relationship, So if the water cement
ratio increase that’s mean we can observe a high slump and vice versa.
of engineering materials specific measurements that describe the quality of
engineering materials. Properties of engineering materials are also expressions
in which the designer explains his needs for materials that will resist loads,
breakage, fragmentation, chemical reactions, radiation and heat . The
properties also benefit from the comparison basis. There aren’t two parts of the material have
the same properties precisely and precisely because of the factors exposed to
the material during the formation processes or time processes or change in
temperature or humidity , and the properties of engineering materials are
divided into several sections , including :
represent the dimensions and shape , density and humidity , etc.
or alkaline or resistance to corrosion , etc.
physic-chemical properties such as water absorption or shrinkage or expansion
due to temperature
properties that represent
resistance , durability , hardness ,
The ratio of
the W/C or through the experiments is verified by the test of the recession
cone and pressure factor test . These two tests are related to the viability of
the concrete. This is done by collecting samples for fine aggregates, coarse
aggregates and cement until the validity of the materials chosen for the
concrete is determined. The permeability of the spaces that are connected to
each other in a way that allows access to water and air through them and the
permeability may be more important than the strength in some cases, as in water
reservoirs to protect them from the dangers of iron, which leads to increase
the size of concrete and thus the occurrence of cracks and expulsion of the
concrete cover over the iron The most important factors affect the permeability
is the proportion of water for cement as the greater permeability while the
lack of water leads to difficulty of the dam and thus increase permeability
It is a
material consisting of cement, sand , water with the addition of kind of aggregate
, such as coarse of fine . Concrete is one of the most important building
materials in the modern era, especially with iron reinforcement to become
reinforced concrete (e.g 1:5:3 1 part of
cement 5 part of fine aggregate 3 part of coarse aggregate ) . The romans are
the first to use concrete in history, about 2000 years ago.
Fine Aggregate (sand): Fine
aggregate concrete consists of a mixture of Portland cement, fine aggregate
(sand) and water, so proportioned and mixed as to provide a pump able fine
aggregate concrete. Fine aggregate concrete has a typical mix water/cement
ratio of 0.65 to 0.75.
of fine aggregate concrete into the fabric forms causes a reduction in the
water content by filtering excess mixing water through the permeable fabric.
The reduction of mixing water substantially improves the water/cement ratio of
the in-place fine aggregate concrete thereby increasing its strength and
durability. With a typical loss of approximately 15% of the total mixing water,
27 cubic feet (or 1.0 cubic meters) of pumpable fine aggregate concrete will
reduce to approximately 25 cubic feet (0.93 cubic meters) of hardened concrete.
The mixing water reduction will also result in an increase of approximately 8
percent in the sand and cement per cubic yard (cubic meter) of concrete
aggregate : The coarse particles are larger than 4.75 mm in
diameter and have a diameter of between 9.5 mm and 37.5 mm ,It can also be
initial, secondary, or rearranged . The primary resource is recycled . The
coarse aggregate is obtained from gravel and crushed rock The gravel is the
vast majority of coarse aggregate and is used in concrete with crushed stone
Cement: is a material that hardens and is
that are bonded to cement are either hydraulic or non-hydraulic (hydraulic
cement such as Portland cement) which solidifies due to moisturizing and is an
interaction between the cement powder and anhydrous water and has a chemical
reaction . Thus, they can harden underwater or when constantly exposed to wet
weather. The chemical reaction results in hydrates that are not very water-soluble
and so are quite durable in water. Non-hydraulic cements do not harden
underwater; for example, slaked limes harden by reaction with atmospheric
Water: When water is
added to cement, each of the compounds undergoes hydration and contributes to
the final concrete product. Only the calcium silicates contribute to strength.
Tricalcium silicate is responsible for most of the early strength (first 7
days). Dicalcium silicate, which reacts more slowly, contributes only to the
strength at later times. Tricalcium silicate will be discussed in the greatest
Concrete: Concrete must be strong enough to withstand the structural and service
loads which will be applied to it and must be durable enough to withstand the
environmental exposure for which it is designed. If concrete is made with
high-quality materials and is properly proportioned, mixed, handled, placed and
finished, it will be the strongest and durable building material. Below are the
properties of 1.hardened concrete: Pressure
resistance: Is the ability of material to resist the forces pressing a pivotal
role. And when you reach the limits of compressive strength, shatter article.
Concrete can be manufactured to have a high compressive strength, many of the
concrete with a compressive strength greater than (50 MPa), while not exceeding
compressive strength of some materials, such as sandstone, about (5 to 10 MPa (
resistance: The steel sheet pile features water-profess,
tensile resistance, repetitive use, etc. It can be applicable for permanent
structures, such as wharfs, freight yards, revetment, breakwaters, diversion
dikes, buoys, shipyards, sluices, foundation treatment, cutoff walls and water
barriers, and for temporary structures, such as mining retaining walls,
soil-and-sand-collision-preventing plate, temporary revetment, cofferdam
projects, closed and temporary central islands, and sheet pile retaining walls
to bending: This SCAN-test Method specifies a procedure, based on
principle, for determining the resistance to
the force required to bend a test piece
4.Workability: The ability
of fresh concrete to fill the various shaped form is called workability of
concrete The operation of the concrete depends on the mixing of the fine
elements , Such as temperature and water quantity, and high operating
efficiency can cause separation of concrete
Table 1 : the
first slump cone test
Table 2: compaction factor test which is the second test
In this test there is two
factors influence on concrete workability:
First factor is w/c ratio, as seen from the results that the increase in
the w/c ratio due to increase in the compaction factor of the concrete mixture
and decrease in workability, that’s mean the relationship between w/c ratio and
workability of concrete is inversely proportional.
Second factor is compaction, we note from previous results that the
weight of the mixture increased after compressing, this is due to the filling
voids which existed before the compress in the mixture, this process will
increase the workability of concrete, that means the relationship between
compression and the workability of concrete is a directly proportional.
behavior for materials:
effecting beams: Concrete affecting on the structural behavior in
beams, Reinforced concrete are subjected to repeated impact loads. In such
concrete like beams are also subjected to impulsive forces and impact loads.
Reinforced concrete also affects the beam column joints and columns. (Concrete
columns are vulnerable to impact loads). Higher modes of vibration, strain rate
effect confinement effects as well as vehicle specific parameters further
effect the behavior of columns.
effecting Structural frames: Mechanical loads like the water tank
weight will affect concrete structural frame. An appropriate size of structural
frame should be designed.
effecting behavior in beams: Sizes of aggregate effects shear
strength of reinforced concrete beams. Size should be less than 20mm otherwise
voids will be there in concrete. Porosity in aggregate will corrode the beam
(same for columns).
effecting columns: Coarse aggregate is angular shaped so interlocking
property has rough texture which bonds well to concrete ,main force working in
columns is compression so it will make a strong structured column.
effecting floors: Floor will not get proper finishing because aggregate
is angular and not round. Round aggregate is more vulnerable and hence better
finishing is obtained.
effecting machine bases: Aggregate size is small, so it is not economical
for machine bases, so a larger size of aggregate can be used as the cement used
in coating will be less.
effecting behavior in beams: Particle size distribution of sand is
good, so it will create less voids in structure. As the sand is manufacturing
and not natural, it is free from dust and silt. Sand fills the gaps in coarse
structure to give strength. Aggregate will not tend to carry load in structure
to the same extent as the coarse aggregate, fine aggregate must be durable that
it will not break away at concrete surface.
effecting floors: Sand is fine so it gives good finishing to floors and
effecting behavior in beams: Ultimate compressive strength and
rate of strength, development of concrete is strongly influenced by the
chemical reactivity of the Portland cement. Cement with a higher proportion of
C3S (component) gives a higher early strength in beams and allow for higher
earlier removal of foam work.
effecting columns: It creates a strong bond between fine and coarse
aggregate in concrete and reduces voids of porosity in concrete and gives more
compressive strength in columns, also making a permeable structure which
resists corrosion in steel reinforcement.
floors: If the quantity of cement is more, there will be good finishing in
different types of materials and the properties of these types .we explain the
cement and its properties and types, also explaining of coarse and fine
aggregate and what’s the difference between them
many materials which can able used for construction engineering .
important in construction area to construct projects