This chapter will describes
the general background for study, the objectives, scopes of the work and also
the structure for the research.
Concrete is known as the
extraordinary structural material or as one of the composite material for
construction used (Prabhu et al., 2014). Concrete will be continued dominant as
construction material with the civilization and development of countries since
“man uses no materials but only water in such tremendous quantity”, mentioned
by Brunauer and Copeland (1964). It is widely been used for the production of
bridge, foundation architectural structure and pavement. Therefore,
developments on the various types of concrete for making more alternative
construction materials are attributed over the year. Classification of concrete
is mainly depending on the density of concrete. It can minimise the building
dead load and also contribute to the economic structural design due to its low
density of lightered concrete (Narayanan and Ramamurthy, 2000).
Aggregates are one of the
essential element for concrete production and have the characteristics of
volume stability, resistant to erosion and desired to the final product with
the binding medium such as ordinary Portland cement, water, super-plasticiser,
lime and others. Construction aggregates are also as granular materials, for
example stone, crushed stone, gravel and others which are commonly application
for the construction works such as residential, commercial, industry,
infrastructure and others related activities.
Annually, there is 8 to 12
million tonnes of natural aggregates consumption for the concrete since the
aggregate occupy 70 % to the overall volume (Devi and Gnanvel, 2014). Structural
concrete is commonly and wisely used for most of the construction activities
(Hosseini et al. 2009). Meanwhile, there are huge amount of natural resources
and raw materials are used to produce concrete all over the worldwide (Altwair
and Kabir, 2010). Nowadays, there are 1.5 billion tons of cement, 11 billion
tons of sand and aggregate consumed to produce concrete per year by
construction industry (Shafigh et al., 2013).
As the result, the high
demand of natural aggregates have caused irreparable damage to the environment
and reduced sharply for the resources of natural aggregate. The conservation of
natural resources and environment protection become concern of modern
development. Therefore, new sustainable development solutions are required to
minimise the general natural resources comsumption, environmental pollution and
also the huge amount of the industrial waste production (Rangan, 2008). Moreover,
thr concrete industries need to shoft the model towards sustainable production.
According to Mo et al (2015), investigation on the convection of recycled or waste
product into potential construction materials has motivated researchers to
fulfil the sustainable development.
Besides, the recycling of
construction and demolition wastes has been recognized where the unwanted by
products are potential to conserve natural resources and minimise the energy
consumption in production process (Murali et al., 2012). It is also
a standard alternative for construction and maintenance in some of the
particular countries where there is a shortage of construction aggregate.
Nowadays, the innovation on
the recycled or industrial by product as the construction materials is
popular. The new development of high
techniques for the waste management and the used of residues via productive
method are the main interested and concern area for researchers recently
(Manikandan and Ramamurthy, 2007). So, researchers investigate hard on the bulk
use of available residues for construction materials. Also the modified of
waste materials and utilise it is able to avoid depletion of natural resources
and reduce the overall cost for disposal (Bijen and Van der Wegen, 1985). According
to Bahoria et al. (2013), utilisation of industrial waste as construction
materials is the ecological option to minimise the waste disposal issues
besides conserving the natural resources.
The lightweight aggregates
are generally categorised into natural and artificial. For natural, it consists
of diatomite, volcanic cinders, pumice, scoria and tuff. The artificial
aggregate is from modified naturally materials, for example expanded clay,
slate, shale, vermiculite and perlite which process iunder high temperature and
also industrial by-product such as expanded blast furnace slag, sintered
pulverized fuel ash (Shafigh et al., 2010). According to Emdadi et al (2014), the
lightweigh aggregate gives cost effective, viability economies and structural
stability because there is more versatile in structure with lower weight (Zhang
and Poon, 2015).