11 | Indonesian Journal of Science & Technology, 3 Issue April 2018 Indonesian Journal of Science &Volume Technology 3 .
1, .
11-17 Hal 1-10 Indonesian Journal of Science & Technology Journal homepage: http://ejournal.
edu/index.
php/ijost/ Study on Durability of the Concrete of Sanitation Network in Ouargla Algeria Under the Existence of Sulphates Attack Mohammed-Amin Boumehraz 1*.
Mekki Mellas 2.
Abdelouahed Kriker 3 Department of civil engineering, faculty of science and technology, university of Biskra Ae Algeria.
Department of civil engineering, faculty of applied sciences, university of Ouargla Ae Algeria.
Correspondence: E-mail: amine18gc@yahoo.
ABSTRACT
The objective of this research was to evaluate pipes for domestic applications in Ouargla Algeria.
The experiment procedure was done by investigating the sanitation networks as a function of type of pipes, concrete used, and waste concentration .
s sulfates and hydrogen sulphide compositio.
The analysis was also completed by the comparison between the realistic pipe condition and the pipe specimen control in laboratium.
The results showed that decreases in mechanical strength of the pipe were obtained.
The compressive strength of the specimens has decreased down to 3% after 1 year.
When exposing the specimen to hydrogen sulphide gas, a rapid deterioration was obtained since 90 days of expossure.
Further, the worst change in compressive strength was found, in which the reduction of compressive strength was found down to 40%.
ARTICLE INFO
Article History:
Submitted/ Received 30 Nov 2017
First Revised 03 Jan 2018
Accepted 19 Feb 2018
First available online 09 Mar 2018
Publication Date 01 Apr 2018
____________________
Keyword:
Durability.
Concrete.
Sanitation network.
Waste water.
H2S gas.
A 2018 Tim Pengembang Jurnal UPI
INTRODUCTION
The sanitation network of Ouargla is an important system.
Majority of people in this place connect the sanitary with the sewer system.
Although most sewer system is classified as a domestic-type wastewater, the sanitary seemed to be beyond the standard from domestic wastewater.
The main reason is because this saintary system has a correlation to the discharged wastewater from industry.
Indeed, this could be from the inappropriate wastewater treatment (Boumehraz & Mellas.
The other factor obtained from this sanitation is the high contamination of sulphates and hydrogen sulfide (H2S) (Nielsen & Hvitved-Jacobsen, 1.
It is also reported that the concentration of these contaminants depends on the temperature and relative humidity, and the maximum values are obtained in summer session (Pebriyanti et al.
, 2.
Boumehraz.
Mellas.
Kriker.
Study on Durability of the Concrete of SanitationA | 12 The gas sometimes reaches concentration of 100 ppm.
H2S gas is usually created as a result of organic decomposition in anaerobic bacterial The concentration of this gas must be considered and has a threshold at 3 to 6 mg/L (Estoup & Cabrillac, 1.
Although H2S gas can be oxidized when contacting with air by aerobic bacteria, the existence of this chemical is toxic.
Further, to oxidize H2S, 2% to 6% of oxygen (O.
is required.
Although the oxidation is good to decrease the toxicity of the H2S, the oxidation process creates problems because of the sulphate formation that can corrode pipe (Ryckebosch et al.
In other problems, when H2S gas condenses on the walls of sewer networks.
H2S is converted by anaerobic bacteria, reacting with moisture to form a strong and highly corrosive acid to the plates as sulfuric acid (H2SO.
(Jensen et al.
, 2.
In the case of pipe, most of the components are gypsum.
The gypsum (CaSO4.
2H2O)
is obtained by the reaction between portlandite (Ca(OH).
and the outer sulphates.
The ettringite formation (C3A.
3CaSO4.
32H2O) is the result of the reaction between gypsum and anhydrous calcium aluminate.
The reaction for the formation of these materials involved sodium sulphate (Na2SO.
and magnesium sulphate (MgSO.
with calcium hydroxide (Bassuoni and Nehdi, 2009.
Prasad et , 2.
The reaction can written as Ca(OH)2 Na2SO4 2H2O Ie CaSO4.
2H2O 2NaOH Ca(OH)2 MgSO4 2H2O mechanical strength and reduce the reaction with the calcium aluminate (C3A) of about to 8% (Bassuoni & Nehdi, 2.
The contact between the sulphuric acid and portlandite (Ca(OH).
results gypsum (CaSO4.
2H2O).
Then, the contact between the gypsum and the anhydrous calcium aluminate (C3A) .
CaO.
Al2O.
3CaSO4.
3H2O).
Finally, ettringite is a friable material that forms from the incomplete reaction of the sulphuric acid and the cement paste (Etokov et al.
, 2.
Messaoudene obtained a reduction of compressive strength by 41% (Messaoudene et al.
, 2.
When temperature is lower then 15CC, the thaumasite (CaSiO3.
CaCO3.
CaSO4.
15H2O) was formed.
This material is produced by reactions between the hydrated calcium silicates (CSH), sulfates, and carbonates ions (Bassuoni & Nehdi, 2.
SO4Oe2 3Ca 2 3CO3Oe2 3SiO3Oe2 15H2O Ie 3CaOSiO2.
CO2.
SO3.
15H2O
Here, the present work was to investigate degradation mechanism and physicochemical of organic material in concrete specimens in the real aggressive environment as the building blocks of pipes and manholes used to sanitation in the Ouargla region.
This information is important since the organic material can results other chemicals and can not be predicted easily (Permatasari et al.
, 2016.
Anshar et al.
, 2.
The organic materials can be changed by the additional oxygen and light (Nandiyanto et al.
, 2.
We believe that this research will give information regarding the strategies for against corrosion phenomena.
Ie CaSO4.
2H2O Mg(OH)2 C3A 3CaSO4.
2H2O 26H2O
Ie C3A.
3CaSO4.
32H2O
The additions of pozzolane during the hydration of cement can increase the METHOD DOI: http://dx.
org/10.
17509/ijost.
p- ISSN 2528-1410 e- ISSN 2527-8045 13 | Indonesian Journal of Science & Technology.
Volume 3 Issue 1.
April 2018 Hal 1-10 This study used prismatic mold dimensions .
mm3 according to European standards NF EN 12390-1 and NF P 18427, for the manufacture of concrete specimens.
After pouring the concrete, the specimens were kept in the molds in the indoor lab for 24 hours, for curing concrete.
Table 1 summarizes the concrete mixture compositions of The cement used are Sulphate Resistant Cement (CEM I 42.
5 N-ES) from the Lafarge company.
Physicochemical properties of the cement are shown in Table 2.
Table 1.
Proportions of tested concrete mixtures Component Unit Cement (Kg/m.
Fine aggregate (San.
g/m.
Coarse aggregate .
g/m.
W/C Table 2.
Physical and chemical properties of cement Notes Unit Normal consistency in cement paste (%) Mass per unit volume .
/cm ) Finesse according to Blaine's method Compressive strength 28 days (MP.
Initial time of setting .
at 20 A C Final time of setting .
at 20 A C SiO2 (%) Al2O3 (%) Fe2O3 (%) CaO (%) MgO (%) K2O (%) Na2O (%) SO3 (%) CaOlibre (%) Cl- (%) C3S (%) C2S (%) C3A (%) C4AF (%) CaO.
L (%)
Gypsum (%) 24,85 5,28 3,73 58,71 2,39 0,77 0,27 2,12 0,55 0,06 57,00 19,00 4,00 14,00 1,00 5,00 are presented in Table 3.
The maximum size of coarse aggregate was 15 mm, and the maximum size of fine aggregate or sand was 5 The sand is silica.
Table 3.
Physical and chemical properties of aggregate apparent density .
/cm.
Fine aggregate 1,53 Coarse 1,24 absolute density .
/cm.
2,59 2,60 Equivalent of sand (%) 73,21 Property of aggregate (%) Brittleness of sand (%) Coefficient (%) 13,97 1,32 23,57 CaSO4.
2H2O(%)
CaCO3(%) Cl-(%) NaCl(%) 1,86 1,50 0,015 0,026 4,59 0,023 0,036 Insoluble (%) SO4-2(%) 90,21 Traces 30,26 Traces A series of specimens were cured with drinking water condition .
emperature of 20 A 2 AC).
Other specimens were conserved in the basin of waste water in the Ouargla.
Chemical analysis of waste water in the basin is shown in Table 4.
Table 4.
Results of analysis of global mineralogical parameters of wastewater Ions Unit Ca 2 .
g/L) Mg 2 .
g/L) K .
g/L) Na .
g/L) SO4-2 .
g/L) Cl- .
g/L) The last specimen is exposed to hydrogen sulphuric (H2S) gas, which is placed in a manhole closed of the Ouargla aiming to ensure a high concentration of H2S.
Figure 1 presents concrete specimens curing in different environment conditions.
The physical and chemical properties of coarse aggregate and the fine aggregate used DOI: http://dx.
org/10.
17509/ijost.
p- ISSN 2528-1410 e- ISSN 2527-8045 M.
Boumehraz.
Mellas.
Kriker.
Study on Durability of the Concrete of SanitationA | 14 Figure 1.
Concrete specimens curing in different environment.
RESULTS AND DISCUSSION
Compression test was conducted in the lab by using of prismatic specimens .
x70x70 m.
according to European Standard EN 12390-3.
The results of compressive strength the concrete specimens conserved in different environment are presented in Figure 2.
As shown in Figure 2, the compressive strength of the specimens control is greater than those specimens preserved in the waste The specimen exposed with H2S gas is the lowest for compressive strength value.
The compressive strength for specimens conserved in waste water increases continuously up to 365 days, and the maximum value of strength reaches is 32.
65 MPa.
For the specimens exposed to H2S gas, the value of compressive strength increases continuously up to 90 days, where the maximum strength is 04 MPa.
But, from 90 to 365 days, the value of compressive strength reduced down 41 MPa.
The results confirmed the negative effect of H2S gas on durability of concrete.
The X-ray diffraction analysis shows the skin of concrete specimens preserved in different environment conditions (Figure 3 and .
As shown in the figures, the formation of ettringite was found in specimen exposed with H2S gas .
etected in peaks of 43, 48, and 50C).
The formation of portlandite for specimen conserved in waste water was found at peaks of 12 and 32C.
The results confirmed the acceleration for degradation of the specimens exposed to H2S.
CONCLUSION
The conservation of pipe must be considered since the physicochemical properties of pipes change when contacting with chemicals.
It is found that the concrete specimens in wastewater decreases by 3% for compressive strength after 365 days.
For concrete specimens exposed to H2S gas, rapid deterioration was found after 90 days.
Then, when exposing H2S gas from 90 to 365 days, reduction in strength to 40% was found.
The change of mechanical strength is due to corrosion phenomena as an impact from the existence of H2S.
Thus, for increasing durability of pipe and manholes in Ouargla, substitution of pipe and manhole by other material is DOI: http://dx.
org/10.
17509/ijost.
p- ISSN 2528-1410 e- ISSN 2527-8045 15 | Indonesian Journal of Science & Technology.
Volume 3 Issue 1.
April 2018 Hal 1-10 Figure 2.
Compressive strength of concrete specimens conserved in different environments.
Figure 3.
Analysis by X-ray diffraction of specimens conserved in the waste water.
DOI: http://dx.
org/10.
17509/ijost.
p- ISSN 2528-1410 e- ISSN 2527-8045 M.
Boumehraz.
Mellas.
Kriker.
Study on Durability of the Concrete of SanitationA | 16 Figure 4.
X-ray diffraction of specimens exposed to H2S gas.
ACKNOWLEDGEMENTS
The authors wish to thank university of Biskra and university of.
Algeria.
AUTHORSAo NOTE The author.
that there is no conflict of interest regarding the publication of this article.
Authors confirmed that the data and the paper are free of plagiarism.
REFERENCES