1. SCHOOL OF ARCHITECTURE, BUILDING AND DESIGN
BACHELOR OF QUANTITY SURVEYING (HONOURS)
Research on Building Material - CONCRETE
Kevin Lee Hee Xian 0315192
Jake Sia Chyi Sern 0314396
Melvin Lim Wei Jien 0315772
Voon Sze Lun 0315032

2. Table of Content
Introduction
Concrete Degradationand Defects:
2.1 Deformation of the surface
2.2 Cracking of the surface
2.3 Disintegration of the surface
2.4 Other defects
Environmental Impact of Concrete:
3.1 Carbon dioxide emissions and climate change
3.2 Raw material used
3.3 Water wastage
3.4 Water pollution
3.5 Energy
3.6 Health concern
Conclusion
Reference

3. Introduction
There are many concrete defects that usually occur during construction. These defects
are broken down into four groups based on observation: deformation of the surface,
cracking of the surface, disintegration of the surface and other defects.

4. DEFORMATION OF THE SURFACE
Deformation of concrete surface can occur in 3 different ways:
Curling
Causes: moisture in the concrete.
Location: edges and corners.
Warping
Causes: temperature change in the concrete.
Location: edges and corners.

5. Blistering
Causes: delamination of surface mortar
Location: at the surface of the concrete where mortar is laid.

6. CRACKING OF THE SURFACE
Cracking of the surface of concrete can occur in many ways. A few of which are most
common are these 4 different cracks:
Plastic Shrinkage
Cracks that are parallel to the concrete slab.
Causes: shrinkage of the concrete that take place when the concrete is still fresh
Crazing
Cracks that seem like random fissures
Causes: rapid evaporation of moisture from the concrete surface

7. Map-cracking
Random fissures however bigger than crazing
Causes: alkali-silica reaction in the concrete.
Structural failure cracking
Has no specific crack
Causes: change in elevation.

8. DISINTEGRATION OF THE SURFACE
Disintegration comes in 3 different type of distress:
Dusting
Causes: saturation of carbon dioxide during finishing making a weak layer of cement on
the surface of concrete.
Ravelling or Spalling
Causes: dislocation of pieces of concrete at the joint edges.

9. Flaking
Causes: blistering which is the breaking of pieces from the surface of the concrete.

10. OTHER DEFECTS
These defects are caused by the mortar not filling the spaces between the aggregate
particles.
Bugholes
Small voids in the surface of vertical concrete placements.
Honeycombing
Large voids in the surface of vertical concrete placements.

11. Environmental Impacts of Concrete
1. Carbon dioxide emissions and climate change
- The cement industry is one of two primary industrial producers of carbon dioxide,
creating up to 5% of worldwide man-made emissions of this gas, of which 50% is
from the chemical process and 40% from burning fuel.
- Cement manufacture contributes greenhouse gases both directly through the
production of carbon dioxide when calcium carbonate is thermally decomposed,
producing lime and carbon dioxide, and also through the use of energy, particularly
from the combustion of fossil fuels.

12. 2. Raw material used
- Concrete is made from raw material such as limestone, marl and chalk. These are the
most common sources of calcium in the cement. All these raw materials comes from
mining, and mining will affect the echo system as lots of deforestation, water
catchment, water natural flow is disturbed.
3. Water wastage
- Few billion tons of water has wasted just because of the making of concrete, as
because water is one of the main sources in making concrete.

13. 4. Water Pollution
- Another environmental issue with cement and concrete production is water pollution.
- At the batch plant, wash water from equipment cleaning is often discharged into
setting ponds where the solids can settled out.
- Some returned concrete also gets put into settling ponds to wash off and recover the
aggregate.
5. Energy
- Energy consumption is the biggest environmental concern with cement
and concrete production. Cement production is one of the most energy intensive
of all industrial manufacturing process.

14. - Including direct fuel use for mining and transporting raw materials, cement
production takes about 1,758 kWh for every
ton of cement.
6. Health concerns
- The presence of some substances in concrete, including useful and unwanted
additives, can cause health concerns.
- Working with wet concrete requires a number of precautions, primarily to protect the
skin from the high alkalinity that can cause chemical burn.

15. Conclusion
Although concrete is vital and important for construction especially in a developing country like
ours, in order to help reduce or stop the environmental impacts of concrete, we should also try to
reduce the amount of concrete usage by using alternative types of concrete such as fly ash.
Refrences
1. Cement.org.
Evaluating Concrete Defects
In-text: (Cement.org, 2014)
Bibliography: Cement.org. (2014). Evaluating Concrete Defects. [online] Retrieved
from: http://www.cement.org/for-concrete-books-learning/concrete-technology/concrete-
design-production/evaluating-concrete-defects [Accessed: 13 Apr 2014].
2. Babor B. Plian D. Judele L. (2009) Environmental Impacts of Concrete. [online] Retreived
from: http://www.ce.tuiasi.ro/~bipcons/Archive/161.pdf [ Accessed: 20 Apr 2014]
3. Yahoo (2012) How does concrete affect our environment? [online] Retrieved from:
https://malaysia.answers.yahoo.com/question/index?qid=20120701010738AA6Fl9t [Accessed: 20 Apr
2014]
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