Study on the effect of Rheology on the Compressive Strength of Concrete
Chapter 1
INTRODUCTION
1.1 Background of the study Concrete is widely used in constructing buildings, houses and other structures, but in order to have a strong structure there are factors to be considered. One of which is compressive strength, this is important to the structure especially if it is a high rise building and will be used commercially. The compressive strength of a concrete is important especially to the column of a structure because it resists compression force. Columns must have sufficient compressive strength to carry loads acting upon it. Superplasticizer is often used to reduce the water content of SCC. Problem is then regarding the compressive strength of the SCC arises, whether increasing superplasticizer content increases compressive strength or vice versa or increasing Viscosity Modifying Agent (VMA), will alter its compressive strength.
Nowadays there are many construction firms which are using self-compacting concrete (SCC). It is used when a structure is constructed with a large quantity of reinforcement, compacting manually will be difficult to avoid honeycombs or voids. Materials that were used for this kind of concrete are Viscosity-Modifying Agent (VMA) that will make the SCC stable, pozzolanic materials will help SCC to flow better (EFNARC, 2005).
Superplasticizer (SP) is a type of water reducers; however, the difference between superplasticizer and water reducer is that superplasticizer will significantly reduce the water required for concrete mixing. Effects of superplasticizer are obvious, to produce concrete with a very high workability or concrete with a very high strength. (Neville, 2005)
One of the latest innovations is the development of improved Viscosity Modifying Admixture (VMA) also referred to as stabilizers. Most VMA’s have little effect on other concrete properties in either the fresh or hardened state but if used at high dosage, it can affect the setting time and or the content and stability of entrained air.
INTRODUCTION
1.1 Background of the study Concrete is widely used in constructing buildings, houses and other structures, but in order to have a strong structure there are factors to be considered. One of which is compressive strength, this is important to the structure especially if it is a high rise building and will be used commercially. The compressive strength of a concrete is important especially to the column of a structure because it resists compression force. Columns must have sufficient compressive strength to carry loads acting upon it. Superplasticizer is often used to reduce the water content of SCC. Problem is then regarding the compressive strength of the SCC arises, whether increasing superplasticizer content increases compressive strength or vice versa or increasing Viscosity Modifying Agent (VMA), will alter its compressive strength.
Nowadays there are many construction firms which are using self-compacting concrete (SCC). It is used when a structure is constructed with a large quantity of reinforcement, compacting manually will be difficult to avoid honeycombs or voids. Materials that were used for this kind of concrete are Viscosity-Modifying Agent (VMA) that will make the SCC stable, pozzolanic materials will help SCC to flow better (EFNARC, 2005).
Superplasticizer (SP) is a type of water reducers; however, the difference between superplasticizer and water reducer is that superplasticizer will significantly reduce the water required for concrete mixing. Effects of superplasticizer are obvious, to produce concrete with a very high workability or concrete with a very high strength. (Neville, 2005)
One of the latest innovations is the development of improved Viscosity Modifying Admixture (VMA) also referred to as stabilizers. Most VMA’s have little effect on other concrete properties in either the fresh or hardened state but if used at high dosage, it can affect the setting time and or the content and stability of entrained air.
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