Kurnia 2019 IOP Conf. Ser. Mater. Sci. Eng. 602 012076

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IOP Conference Series: Materials Science and Engineering

PAPER • OPEN ACCESS

Corrosion potential of reinforced steel in reinforced concrete in

Kabupaten Bireun: Analysis of groundwater content used as a concrete mixture

To cite this article: R D I Kurnia et al 2019 IOP Conf. Ser.: Mater. Sci. Eng. 602 012076

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Conference on Innovation in Technology and Engineering Science IOP Conf. Series: Materials Science and Engineering 602 (2019) 012076

IOP Publishing doi:10.1088/1757-899X/602/1/012076

Corrosion potential of reinforced steel in reinforced concrete in Kabupaten Bireun: Analysis of groundwater content used as a concrete mixture

R D I Kurnia¹, Suhaimi¹, S Huzni², and S Fonna²

1Department of Civil Engineering, Almuslim University, Jalan Almuslim Matangglumpangdua, Bireuen, Indonesia

2Department of Mechanical and Industrial Engineering, Faculty of Engineering, Syiah Kuala University, Banda Aceh

E-mail: [email protected]

Abstract. The use of groundwater as a mixture in making reinforced concrete is common in Bireun District, Aceh. This research is the initial stage of investigating the relationship between the quality of concrete and water resistance as a mixture in Bireun Regency. At this stage, the research focus is directed to find out what elements are contained in groundwater in five locations in Kabupaten Bireun, namely Gampong Paya, Gampong Teupok Teungoh, Gampong Pulo Lawang, Gampong Lhok Awe Baroh and Gampong Lhok Awe. Water content testing is carried out by referring to SNI 06-6989.14-2004 and SNI 06.6989.19: 2009. The results analyzed and compared with the reference of ASTM C 1602 M-04 standard. Laboratory test results show that chloride, sodium, sulfate and dissolved oxygen differ from location to location. Chloride content in two locations, Gampong Paya and Tumpok Teungoh, is far above the standard content set in the ASTM C 1602 M-04 standard. While at three other locations, chloride content was below the limit of ASTM C 1602 M-04. Investigation of the potential for corrosion of reinforcing steel in reinforced concrete using groundwater as a mixture in five locations will provide further information.

1. Introduction

Kabupaten Bireuen is part of the Aceh region located in the coastal area. Various potentials and attractiveness in the field of marine cause this region to continue to grow and develop rapidly.

Construction of structures and infrastructure is carried out in line with regional development and population growth. Various facilities and infrastructure are built such as residential buildings, places of worship, office buildings, bridges, and various other public facilities. The quality of the facilities and infrastructure built, especially reinforced concrete, will be strongly influenced by the mixture used. One of the main ingredients in making concrete is water. High chloride content in concrete mixed water can trigger the corrosion process in steel reinforcement in concrete [1, 2]

The use of groundwater as a concrete mixture is very common in Kabupaten Bireun. The chemical content of groundwater and its influence on the quality of buildings in Kabupaten Bireun is not yet

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This research is a preliminary step in investigating the influence of groundwater as a concrete mixture on the corrosion phenomenon of reinforced concrete. The main focus of the study at this stage is to examine the content of chloride, sodium, sulfate and dissolved oxygen (DO) in groundwater in five selected locations in the Bireun region.

2. Method

2.1. Sampling location

The groundwater investigated in this study came from five locations in Kabupaten Bireun, namely Gampong Paya, Gampong Teupok Teungoh, Gampong Pulo Lawang, Gampong Lhok Awe Baroh and Gampong Lhok Awe Gampong (figure 1). The main consideration in determining the location is the level of development and population density. Also, the location can represent the overall condition of Kabupaten Bireun.

2.2. Chemical composition test

Testing the chemical composition of groundwater samples taken from five locations in Kabupaten Bireun was conducted at the Laboratorium Penguji BARISTAND Industri Banda Aceh (LABBA).

Test parameters and methods used are shown in Table 1.

Table 1. Test Parameters and Methods

No. Test Parameter Test Method

1 Chloride (Cl^-) SNI 06.6989.19.2009

2 Natrium (Na) Atomic absorption spectroscopy (AAS) 3 Sulfate (SO₄) IK.5.04.01.31

4 Dissolve Oxygen (DO) SNI 06-6989.14.2004 3. Results and discussion

The test results of the chemical content of Cl, Na, SO4 and DO for each location are shown in figure 2 through figure 6. High chloride content was found in two locations, namely Gampong Paya and Gampong Teupok Teungoh. The magnitude of chloride is far above the standard specification for mixing water as shown in table 2. The high content of chloride ions in concrete mixed water can trigger the corrosion process in steel reinforcement in concrete [2, 3]. However, its influence in the Kabupaten Bireun area still needs further investigation.

Figure 1. Sampling locations in Kabupaten Bireun

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Figure 2. The chemical content of groundwater from Gampong Paya (in mg/L)

Figure 3. The chemical content of groundwater from Gampong Teupok Teungoh (in mg/L) 2959.7

539.5

360.0 4.8 0

500 1000 1500 2000 2500 3000

Cl- Na SO4 DO

1589.9

381.6

300.0 4.5 0

200 400 600 800 1000 1200 1400 1600

Cl- Na SO4 DO

87.1 107.6

280.0 200

400 600 800 1000 1200 1400 1600

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Figure 5. The chemical content of groundwater from Lhok Awe Baroh (in mg/L)

Figure 6. The chemical content of groundwater from Lhok Awe (in mg/L) Table 2. Standard specification for mixing water (ASTM C 1602 M-04, 2004)

No. Test Parameter Limit

(ppm) mg/L

1 Chloride (Cl^-) 500 499.4

2 Sulfate (SO4) 3000 2996.6

3 Alkalies as (Na2O+K2O) 600 599.3

Sodium and oxygen-dissolved elements are found in groundwater tested with very small amounts.

The effect of these two elements on the process of corrosion initiation is very small compared to chloride ions. Another element found in groundwater in Bireuen Regency is sulfate (SO4). The presence of sulfate elements in concrete mixed water can inhibit the process of cement hydration reactions. Sulfate attacks cause a decrease in strength in cement paste. Sulfate will react with the composition of the concrete matrix and cause a complex reaction [4].

43.5 35.5 43.0

7.6 0

100 200 300 400 500

Cl- Na SO4 DO

34.2 38.8

24.0

8.0 0

50 100 150 200 250 300 350 400 450 500

Cl- Na SO4 DO

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Magnesium sulfate (MgSO₄) reacts with calcium hydroxide Ca (OH) produces calcium sulfate or gypsum (CaSO₄^2-). Furthermore, gypsum reacts with calcium alumina hydrate (CaO.Al₂O₃) to produce calcium sulfoaluminate (3CaOAl₂O₃ 3CaSO₄). The resulting calcium sulfoaluminate is found between cement aggregate and paste. The calcium sulfoaluminate volume is produced three times the volume of calcium aluminate (the original ingredient). This inflating nature of calcium sulfoaluminate causes loss of cement and aggregate paste bonds, which ultimately causes cracks in the concrete [4].

Nevertheless, sulfate content in all locations in Kabupaten Bireun is far below the standard specification for mixing water, so theoretically, the effect of sulfate on reducing the quality of reinforced concrete is minimal.

4. Conclusion

The results obtained from testing, will then be analyzed and compared with the reference of ASTM C 1602 M-04 standard. Laboratory test results show that chloride, sodium, sulfate and dissolved oxygen differ from location to location. Chloride content in two locations, Gampong Paya and Tumpok Teungoh, is far above the standard content set in the ASTM C 1602 M-04 standard. While three other locations, Gampong Pulo Lawang, Gampong Lhok Awe Baroh and Gampong Lhok Awe, chloride content was below the limit of ASTM C 1602 M-04, next step of this work is to investigate the corrosion potential of reinforcing steel in reinforced concrete using groundwater as a mixture in five locations in Kabupaten Bireun to provide further information.

References

[1] Broomfield JP 2007 Corrosion of Steel in Concrete - Understanding, Investigation and Repair, 2nd edition (Taylor & Francis, London)

[2] Fontana MG 1987 Corrosion Engineering 3rd Edition (New York: McGraw-Hill)

[3] Luca Bertolini, Bernhard Elsener, Pietro Pedeferri, Rob Polder 2004 Corrosion of Steel in Concrete, Prevention, Diagnosis and Repair (Weinheim WILEY-VCH Verlag GmbH & Co.

KGaA.)

[4] M. Ridha, S. Fonna, S. Huzni, and A. K. Ariffin 2013 Journal of Earthquake and Tsunami 07(01) 1350004.