SCHOOL OF ARCHITECTURE, BUILDING AND DESIGNBACHELOR 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

Table of Content

Introduction 3

Concrete Degradation and Defects:

2.1 Deformation of the surface 4 - 5

2.2 Cracking of the surface 6 - 7

2.3 Disintegration of the surface 8 - 9

2.4 Other defects 10

Environmental Impact of Concrete:

3.1 Carbon dioxide emissions and climate change 11

3.2 Raw material used 12

3.3 Water wastage 12

3.4 Water pollution 13

3.5 Energy 14

3.6 Health concern 15

Conclusion 16

Reference 17 - 19

Introduction

In this project report, a group of students have to show their research and write out a

report about their findings based on the topic given to them. Concrete is a very common

used material in the construction industry. 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. Other than that, there is environmental impact of concrete

too. The subtopics for the environmental impact are carbon dioxide emissions and

climate change, raw material used, water wastage, water pollution, energy and heath

concern.

3

CONCRETE DEGRATION AND DEFECTS

Deformation of the surface

Deformation of concrete surface can occur in 3 different ways:

Curling

Causes: moisture in the concrete.

Location: edges and corners.

4

Warping

Causes: temperature change in the concrete.

Location: edges and corners.

Blistering

Causes: delamination of surface mortar.

Location: at the surface of the concrete where mortar is laid.

5

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 is 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.

6

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.

7

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.

8

Flaking

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

9

Other defects

These defects are caused by the mortar not filling the spaces between the aggregate

particles.

Bugholes

Small voids on the surface of vertical concrete placements.

Honeycombing

Large voids in the surface of vertical concrete placements.

10

Environmental Impacts of Concrete

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.

11

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.

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.

12

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.

13

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.

Including direct fuel use for mining and transporting raw materials, cement production

takes about 1,758 kWh for every ton of cement.

14

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

In conclusion on the whole area of concrete degradation and defects & environmental

effects, it is important to continue on the advancement of construction technology and

building materials so that living conditions may be improved and accidents may be

reduced, however the condition of the environment cannot be ignored. This is because

when the ecosystem is disturbed it can cause many problems like shortage of food,

pollution or even natural disasters. Hence, this requires detail planning and proper

allocation of resources all for the good of the construction industry, the environment as

well as future generations.

16

References

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. Bam.de

BAM Expertise | Expertise | Safety of Structures | Building Materials | Damage

Mechanisms and Protective Measures

In-text: (Bam.de, 2014)

Bibliography: Bam.de,. (2014). BAM Expertise | Expertise | Safety of Structures |

Building Materials | Damage Mechanisms and Protective Measures. Retrieved 28 April

2014, from http://www.bam.de/en/kompetenzen/fachabteilungen/abteilung_7/fg71/

fg71_ag2c.htm

3. Blog.kryton.com Five Signs of a Leaky Basement

In-text: (Blog.kryton.com, 2013)

Bibliography: Blog.kryton.com,. (2013). Five Signs of a Leaky Basement. Retrieved 28

April 2014, from http://blog.kryton.com/2013/04/five-signs-of-a-leaky-basement/

4. Civil-engg-world.blogspot.com Plastic Shrinkage Cracking in Concrete

In-text: (Civil-engg-world.blogspot.com, 2014)

Bibliography: Civil-engg-world.blogspot.com,. (2014). Plastic Shrinkage Cracking in

Concrete. Retrieved 28 April 2014, from

http://civil-engg-world.blogspot.com/2011/04/plastic-shrinkage-cracking-in-concrete.html

17

5. Concrete floors

In-text: (Concrete floors, 2014)

Bibliography: Concrete floors,. (2014). Concrete floors. Retrieved 28 April 2014, from

http://concretefloors.ca/craze.htm

6. Concrete.org Curling

In-text: (Concrete.org, 2014)

Bibliography: Concrete.org,. (2014). Curling. Retrieved 28 April 2014, from

http://www.concrete.org/Tools/TroubleshootingSurfaceImperfections/Curling.aspx

7. Concretenetwork.com Grey Microtopping Mimics Polished Concrete - The Concrete

Network

In-text: (Concretenetwork.com, 2014)

Bibliography: Concretenetwork.com,. (2014). Grey Microtopping Mimics Polished

Concrete - The Concrete Network. Retrieved 28 April 2014, from

http://www.concretenetwork.com/concrete_overlays_cement/polished-microtopping.html

8. Garageenhancements.ca Why is My Concrete Porch Chipping and Flaking? - Garage

Enhancements Ltd.

In-text: (Garageenhancements.ca, 2014)

Bibliography: Garageenhancements.ca,. (2014). Why is My Concrete Porch Chipping

and Flaking? - Garage Enhancements Ltd. Retrieved 28 April 2014, from

http://www.garageenhancements.ca/Why-is-My-Concrete-Porch-Chipping-and-

Flaking-.htm

9. Lmcc.com Concrete News: Making the Bugholes bug out (concrete bugholes)

In-text: (Lmcc.com, 2014)

Bibliography: Lmcc.com,. (2014). Concrete News: Making the Bugholes bug out

(concrete bugholes). Retrieved 28 April 2014, from

http://www.lmcc.com/concrete_news/0112/Preventing-concrete-bugholes.asp

18

10. Rrmodelcraftsman.com Railroad Model Craftsman - Monster Modelworks Concrete

Paving for multiple scales

In-text: (Rrmodelcraftsman.com, 2014)

Bibliography: Rrmodelcraftsman.com,. (2014). Railroad Model Craftsman - Monster

Modelworks Concrete Paving for multiple scales. Retrieved 28 April 2014, from

http://rrmodelcraftsman.com/reviews/cm_review_monstermodelworks-

concretepaving.php

11. Structuraldesigns.com.au Surface Blistering or efflorecence on concrete surface

In-text: (Structuraldesigns.com.au, 2014)

Bibliography: Structuraldesigns.com.au,. (2014). Surface Blistering or efflorecence on

concrete surface. Retrieved 28 April 2014, from

http://www.structuraldesigns.com.au/FAQs/Problems%20in%20Hot%20Weather/

Surface%20blistering%20during

12. Wikipedia Reinforced concrete

In-text: (Wikipedia, 2014)

Bibliography: Wikipedia,. (2014). Reinforced concrete. Retrieved 28 April 2014, from

http://en.wikipedia.org/wiki/Reinforced_concrete

19