“BIOCONCRETE”
In partial fulfillment of the requirements for
CHM031: Chemistry for Engineers
Submitted to:
Frances Vega
Submitted by:
Junelle Beso
Date
September, 7, 2019
In every constructional design and buildings, we ensured the strength of the building
in order to be resilient in any force that acts against on it. Strength is tremendously important for
any material and any construction project, and a foundation plays an important role for this.
Concrete is an important and very useful property in a building construction because it is an only
property that is cheaper and easier to make but very strong enough to resist comprehensive
stresses. Moreover, concrete is strong, abundant, dependable and tremendously versatile
construction material plus not a combustible substance when used and it is very pliable that can
be easily shaped.
During 600 BC in Rome the Ancient Romans first utilize the concrete material to their
construction projects and by 200 BC; the Romans positively applied the use of concrete in the
majority of their structure making. They used a mixture of volcanic ash, lime, and seawater to
form the mix or mortar and volcanic tuff. Concrete is very significant in today’s world that’s
why this is second most consumed substance next to water and about 10 billion tons are used and
produced every year. Concrete is a composite material, consisting mainly of Portland cement,
water and aggregate (gravel, sand or rock). When these materials are mixed together, they form a
workable paste which then gradually hardens over time. The chemical reaction involved in
producing or making a concrete is that the water causes the hardening of concrete through the
process of hydration. The water reacts with the cement, which bonds the other components
together, eventually creating a stone like material. Hydration is a chemical reaction in which the
major compounds in cement form chemical bonds with water molecules and become hydrates.
Though Concrete is one of the most widely used construction materials, there are lot of
disadvantages accompanying with it. Some of these disadvantages of concrete are modified by
adding admixtures or altering the concrete structure and ingredients. Here are some shortcomings
of concrete as part of building construction; Concrete is a cuasi-brittle material, low tensile
strength, low toughness, low specific strength, formwork is required, long curing time working
with cracks, demands strict quality control. The crack formation is typical phenomenon related to
durability and percolation of cracks may lead to leakage problems, causing deterioration of the
concrete matrix corrosion of embedded steel reinforcement. To solve these problems, the
knowledge of science and engineering are combined to develop a more advanced material so
much so that it can add much strength to the mechanical properties of a concrete. A new term
called BIOCONCRETE which is a special type of concrete invented by a group of microbiology
researchers under the head of Henk Jonkers. Bio concrete is also called as Bacterial concrete or
self-healing concrete. It’s specially made to increase the lifespan or the durability of concrete
structure by the self-healing action of that concrete. There are two things present in bio concrete;
the special bacteria that has to resist the alkalinity and the mechanical stress of concrete and the
chemical precursor to activate the bacteria. The mechanism inside the bio concrete is that cracks
are formed on the surfaced of concrete due to many reasons like shrinkage, inadequate water for
hydration and etc. And so the water is deliberately forced into the crack and the precursor is
activated and this activated precursor intern induces the bacteria to react with the precursor and
for a base of calcium carbonate called limestone.
References
https://www.giatecscientific.com/education/the-history-of-concrete/
https://concretehelper.com/concrete-facts/
https://www.designingbuildings.co.uk/wiki/Concrete
https://engineeringcivil.org/articles/concrete/limitations-concrete-disadvantages-concrete-8-reasons/
https://www.researchgate.net/post/What_is_Bio-Concrete_Self-healing_concrete
