Influence of Magnetic Water on Self-compacting Concrete Using Sulphate Resisting Cement

It is generally observed that the traditional concrete is framed with the compaction of concrete which is often seen as a default. Irrespective of the building structures, it is known fact that the concrete material which must be sturdy enough and compacted be used. The compacting of concrete includes the following procedure: Removal of entrapped air to the maximum density and ensuring attaining that status [1]. Ensure that the steel reinforcement and formwork must be in full contact with these two [2]. These two strengthening points must be ensured so as to strengthen the final product. It is clearly highlighted that through the external force vibrations, the compacting of the conventional concrete is performed. These vibrations are externally emphasized though they are highly incapable of reinforcing of intensive engineering, deep structural members and wall element, where the concrete block strengthens so as to avoid problems like the mechanical properties, durability and quality and enable to complete and reduce the above said problems. Apart from all the above, it is also observed that in this research paper, that if the workability is poor, the high quality of infrastructure is utilized [3]. Moreover, in majority of the cases, it depends on the skilled workers and more energy is emphasized to form concrete shapes. It is more important to develop workability along with the compatibility with the concrete which is also named as self-consolidating concrete, self-leveling concrete, or vibration-free concrete. This has low yield stress, high deformability and moderate viscosity. One can assume that the uniform suspension of solid particles during the transportation and placement until the concrete sets, the above said one is needed with little or no vibration [4]. This self consolidating concrete can be densely filled into every corner of a formwork, totally by means of its own weight without the need for vibrations to compaction for improving the self compacting concrete properties with low cost by using magnetic water. However, the price and expenses of this method is not comparable with their advantages. Thus, most of the researchers majorly focus and concentrate on producing economical concrete with higher strength using new philosophies in designing methods through modern techniques such as magnetic water sources. The government of Russia adopted the federal program entitled “Application of magnetic fields in National Economy”, this academy created a range of documents, ordering their organizations to use magnetic technologies [5]. This is the decision made in order economize on cementing and Ferroconcrete which contains the fly ash and prepared with magnetic water that increases by more than 15 % when it is prepared with normal water. More over for additional strength, they propose fibres in the project [6]. Now a days fibres are most effectively used material in the concrete to reduce crack repair, reduction in shrinkage of concrete and improve the strength properties of concrete along with replaced OPC with (Sulphate Resisting Cement) SRC in the project. SRC is also one type of Portland cement in which the amount of tricalcium aluminate (C₃A) is restricted to lower than 5 %. The reduction of sulphate salts lowers the possibility of sulphate attack on the concrete [7]. In addition to metakaolin as an additive for provide extra strength to concrete [8].

3.1 Test on cement

Sulphate Resisting Cement (SRC) is used when the concrete is exposed to the risk of deterioration due to sulphate attack. It can be used for structural concrete whereas OPC or PPC or Slag Cement is usable under normal conditions. SRC is one type of Portland cement in which the amount of Tricalcium aluminate (C3A) is restricted to lower than 5 % and (2 C3A + C4AF) is lower than 25 % to resist the sulphate attack.

Table 1. Chemical composition of sulphate resisting cement

MetaKaolin is used as binder for cementitious products. Give extra strength and good bonding for the materials [9].

Table 3. Chemical composition of metakaolin

3.3 Tests on fine aggregate

River sand of Zone-II locally available is used, which is free from silt content and waste materials.

Table 5. Test results of fine aggregate

3.4 Test on coarse aggregates

Crushed stone aggregate of maximum size 12.5 mm passing and 10 mm retained are used.

Table 6. Test results of coarse aggregate

3.5 Preparation & test water

The results of tests conducted on normal water and magnetic water, are listed below in the table. In the present investigation work, magnetic water was prepared by placing magnets into the beaker containing water of 985 Gauss magnetic field that was obtained from scientific store. This Magnetic water was produced by placing the beaker filled with water over the magnets for a period of 24 hours. During this time, the magnetic field penetrates through the glass into the water and this magnetized water is used for making concrete [10].

Table 7. Test results of water

3.6 Micro steel fibers

The below mentioned specified micro steel fibers are used in the project to improve the strength characteristics of concrete.

Table 8. Properties of micro steel fiber

It is used for reducing the water- cement ratio of concrete. Specific Gravity of super plasticizer is 1.04.

Test series consisted of 108 cubes and 54 cylinders of 18 different mixes at 18 different ratios of materials. The dimensions of cube specimens are 150 mm × 150 mm × 150 mm and cylinder specimen having dimensions of 300 mm height, 150 mm diameter Tests were conducted after curing the specimens for 7, 14 and 28 days respectively.

Graphs are plotted between compressive strength and % of Admixture added to the mix proportion. Here the compressive strength values varied in 7 Days, 14Days and 28-days is shown in Figure 1.

Graphs are plotted between compressive strength and % of steel fibers added to the mix proportion. Here the compressive strength values varied in 7 Days, 14 Days and 28Days is shown in Figure 2.

Table 10. S.C.C test results for admixture trials where AM is the admixture

Table 11. Admixture optimum test results of compressive strength

Table 13. Steel fibers test results of compressive strength

Note: MK is the metakaolin

Table 15. Metakaolin test results of compressive strength

Table 17. Compressive strength on combination trail with general and magnetic water

 

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Figure 1. Graph between % admixture and compression strength

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Figure 2. Graph between % steel fiber and Compression strength

Table 18. S.C.C test results for cylinder trails

Sample	Slump test (mm)	T50 slump(sec)	L- Box(sec)	V-funnel(sec)	J-ring(mm/sec)	U- funnel (sec)
Admixture	630	1.2	8	8	630/8	22
Steel fiber	650	1.3	9	9	640/9	20
Metakaolin	640	1.5	8	8	610/8	24
Comb + general water	650	1.8	10	8	620/7	23
Comb + Magnetic water	660	2.0	9	9	640/8	22

 

Table 19. Tensile strength results

Sample	7-days		14-days		28-days
	Load(N/mm2)	T.S Mpa	Load (N/mm2)	T.S Mpa	Load (N/mm2)	T.S Mpa
AD	210	2.97	265	3.74	285	4.03
Steel fiber	235	3.24	300	4.24	322	4.55
Meta kaolin	220	3.11	280	3.96	291	4.11
Comb + General water	260	3.67	320	4.52	348	4.92
Comb + Magnetic water	282	3.98	345	4.88	365	5.16

 

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Figure 3. Graph between % metakaolin and compression strength

Graphs are plotted between compressive strength and % of metakaolin added to the proportion of mix. Here the compressive strength values shown at is shown in Figure 3.

This paper explains how the influence of magnetic water influences self compacting and how it strengthens the characteristics of concrete. Due to this purpose, 985 gauss magnetic strength is used to prepare magnetic water. The conclusions based on the above research on this paper are stated as given below:

• The workability of SCC made by magnetic water is observed to be moderately more than that of general water at same water cement ratio. It may be due to the fact that by keeping magnets with water, inter molecular changes occurs, which results in the decrease of pH, hardness and turbidity.
• It is evident from the test results that the Compressive strength of SCC made by magnetic water is higher than that of non magnetic water by 10 %.
• It is also observed that the Tensile strength of SCC with magnetic water is increased by 5 % than SCC with normal water.
• In cost comparison wise Magnetic water self compacting concrete is less than 6.74 % when compare to self compacting Concrete.