Description
CHAPTER ONE
1.0 INTRODUCTION
As it is known, curing conditions affect strength and durability of concrete seriously
as well as sufficient workability, consistency and effective compacting. The
permeability, which is the main parameter affecting concrete durability, is directly
influenced by curing conditions. The water in concrete should be prevented from
moving away in order to form the hydration reactions that occur in the process of
gaining strength of concrete. For this purpose, concrete should be protected by
performing surface irrigation or similar methods before gaining strength [1-3].
Concrete properties such as strength behaviour, water permeability, permeability of
Cl and CO2, crack characteristic are influenced by curing regimes [4-9], curing time
[4-6, 10-13], curing temperature [11, 13-17] and humidity [18-20]. Some related
studies are summarized below:
The effect of accelerated curing on early age compressive and flexural strengths of
mortars containing fly ash in different quantities was investigated by Yazici and
Sezer [21], consequently, it has been determined that strength loss, that occurred
under standard curing conditions at early ages due to addition of fly ash, can be
compensated by hot water curing. Bingol and Tohumcu [1] investigated the effect
of different curing conditions (air curing, water curing and steam curing) on the
compression strength of self-compacting concretes including silica fume and fly
ash. According to the test results, mixture containing silica fume and cured in water
showed the highest compressive strength.
1.1 BACKGROUND OF THE STUDY
Ceramic products are part of the essential construction materials used in most
buildings. Some common manufactured ceramics include wall tiles, floor tiles,
sanitary ware, household ceramics and technical ceramics. They are mostly
produced using natural materials that contain high content of clay minerals.
However, despite the ornamental benefits of ceramics, its wastes among others cause
a lot of nuisance to the environment. As a general note, Omole and Isiorho [1]
reported the devastating influence of solid wastes in the Nigerian community.
Ceramic wastes are separated into two categories in accordance with the source of
raw materials [2]. One category is formed through generated fired ceramic wastes
by structural ceramic factories that use only red pastes for product (brick, blocks
and roof tiles) manufacture. The second encompasses fired ceramic wastes which
are produced in stoneware ceramic (wall, floor tiles and sanitary ware). Meanwhile
during ceramic production, studies have shown that about 30% of the material goes
to wastes [3,4], and currently they are not beneficially utilized. This attests to the
need for exploring innovative ways of re-using ceramic wastes. Aggregates
constitute about 70% of total constituents in concrete production. The cost is
increasing as a result of high demand from rural and urban communities. Numerous
researchers have identified ceramics as having the potential to replace natural
aggregates [5,6]. Some investigations have suggested that ceramic wastes are good
materials which could substitute conventional aggregates in concrete [7–9]. The
influence of ceramic tiles wastes on the structural properties of concrete made using
laterite was recently investigated [10]. It was reported that ceramic based laterized
concrete performed considerably well when compared to the conventional concrete.
Overall, ceramic waste utilization can solve problems of aggregate shortages in
various construction sites. Moreover it can reduce environmental problems related
to aggregate mining and waste disposal. However, most of the previous
investigations were carried out using sanitary ware and electrical insulator
ceramics, with not much information as regards the use of ceramic floor and wall
tiles. Thus, there is a need to explore the usability of ceramic floor and wall tiles,
because these ceramic products are produced at different temperatures which
invariably determine their microstructures. Consequently, the current study
explores the mechanical characterization of concrete made using ceramic floor and
wall tiles wastes from construction and demolition sites as partial replacement of
natural aggregates.
1.2 AIM OF THE STUDY
The main aim of this work is to determine the characterization of using waste
materials such as ceramics as alternative aggregate materials for construction under
different curing temperatures.
1.3 SCOPE OF THE STUDY
This investigation is a part of an extensive study that examines the effect of water
curing temperature change on some hardened properties of ceramic. For this aim,
prepared mortar mixtures were cured in a curing room under same conditions (having
temperature of 20˚C and RH of 95%) during 24 hours from casting. Then, the mortar
specimens were removed from mold and were cured in water under different
temperature conditions until testing day.
Seven different curing processes with curing temperature of 20 and 40˚C were applied.
The effect of curing processes on the 1, 3, 7 and 28-day compressive strength and 28-
day water absorption capacity of mortar mixtures were investigated.
1.5 OBJECTIVES OF THE STUDY
At the end of this study, the effect of different curing temperature processes on the 1,
3, 7 and 28-day compressive strength and 28-day water absorption ratios of cement
mixtures were investigated.
1.6 LIMITATION OF THE STUDY
In this work, the effect of different curing temperature processes only on the 1, 3, 7 and
28-day compressive strength and 28-day water absorption ratios of concrete mixtures
and the specimens cured in water at 20ºC and 40ºC
1.7 ADVANTAGES OF SELF COMPACTING CONCRETE
The main advantages of self compacting concrete are:
1. The permeability of the concrete structure is decreased
2. SCC enables freedom in designing concrete structures
3. The SCC construction is faster
4. The problems associated with vibration is eliminated
5. The concrete is placed with ease, which results in large cost saving
6. The quality of the construction is increase
7. The durability and reliability of the concrete structure is high compared to
normal concrete structures
8. Noise from vibration is reduced. This also reduce the hand arm vibration
syndrome issues
1.8 DISADVANTAGES OF SELF COMPACTING CONCRETE
SCC construction faces the following limitations:
1. There is no globally accepted test standard to undergo SCC mix design
2. The cost of construction is costlier than the conventional concrete construction
3. The use of designed mix will require more trial batches and lab tests
4. The measurement and monitoring must be more precise.
5. The material selection for SCC is more stringent
1.9 APPLICATIONS OF SELF COMPACTING CONCRETE
The major applications of self compacting concrete are:
1. Construction of structures with complicated reinforcement
2. SCC is used for repairs, restoration and renewal construction
3. Highly stable and durable retaining walls are constructed with the help of SCC
4. SCC is employed in the construction of raft and pile foundations
1.10 PROJECT ORGANISATION
The work is organized as follows: chapter one discuses the introductory part of the
work, chapter two presents the literature review of the study, chapter three
describes the methods applied, chapter four discusses the results of the work,
chapter five summarizes the research outcomes and the recommendations.