BACTERIAL CONCRETE - A REMEDY FOR MICRO CRACKS Submitted in partial fulfillment of the requirements For the degree of Bachelor of Engineering By AnsariMohd. ParvezAlam 13CE74 KadriAasad Anwar 13CE86 MakandarImtiyazMehboob 13CE80 Under Guidance of Prof. Junaid Maste Department of Civil Engineering School of Engineering and Technology Anjuman-I-Islam’s Kalsekar Technical Campus Plot No. 2 3, Sector – 16, Near Thana Naka, KhandaGaon, New Panvel, Navi Mumbai. 41026 2015-2016 CERTIFICATE This is to certify that the project entitled “Bacterial Concrete -A remedy for Micro Cracks”is a bonafide work ofAnsariMohd.ParvezAlam(13CE74), KadriAasad Anwar(13CE86), MakandarImtiyazMehboob (13CE80) submitted to the University of Mumbai in partial fulfilment of the requirement for the award of the degree of “Bachelor of Engineering” in Department of Civil Engineering. Prof. Junaid Maste Guide Dr. Rajendra B. Magar Dr. Abdul RazzakHonnutagi Head of Department Director Project Report Approval for B. E. This project report entitled “Bacterial Concrete-A remedy for Micro Cracks”by AnsariMohd. ParvezAlam, KadriAasad Anwar, MakandarImtiyazMehboob approved for the degree of “Bachelor of Engineering” in “Department of Civil Engineering”. Examiners 1 ______________________ 2 ______________________ Supervisors 1 ______________________ 2 ______________________ Chairman (Director) _______________________ Date: Declaration We declare that this written submission represents my ideas in our own words and where others ideas or words have been included; we have adequately cited and referenced the original sources. We also declare that I have adhered to all principles of academic honesty and integrity and have not misrepresented or fabricated or falsified any idea/data/fact/source in our submission. We understand that any violation of the above will be cause for disciplinary action by the Institute and can also evoke penal action from the sources which have thus not been properly cited or from whom proper permission has not been taken when needed. AnsariMohd. ParvezAlam 13CE74 KadriAasad Anwar 13CE86 MakandarImtiyazMehboob 13CE80 Acknowledgement We would like to express our sincere appreciation to all those who contributed to the successful completion of this research investigation. In particular, we would like to thanks the following people. We express our gratitude to our Guide Prof. Junaid Maste for his guidance in completing the research work. His advice, encouragement during the preparation of this report, ideas about findings the research gap and motivation to do the work is highly appreciated. We also thank our beloved HOD Civil Department Dr. R. B. Magar for endless support and guidance, always finds him co-operative and positive in regards with our project discussions. We are extremely grateful to Prof. Abu Sufiyan, Mr.Wasif, Mr. Rounak, and Department of pharmacy for their valuable support without which this project wasn’t possible at all. We really appreciate their extraordinary support. We appreciate Prof. Shafi Mujawar for helping us by providing us with the necessary materials to complete this project. We are thankful to all the Professor of Civil Engineering Department for their guidance and support to this research work, also the nonteaching staff of the department. Abstract Carbonate-producing bacteria have attracted lots of interest as a promising, natural, environmental friendly novel technique to improvement of concrete characteristics. Considerable research has been conducted on utilizing microbial-induced carbonate precipitation to mitigate several concrete problems such as crack repair, reduction and modification of porosity and permeability. Furthermore, bacterial carbonate precipitation (bio deposition) has shown positive influences on compressive strength improvement of concrete. In the meantime, it seems that the study related to the optimum dosage of bacterial solution and its effect on the durability of concrete has not been comprehensively investigated. Therefore, it is decided to carry out an investigation of determining optimum dosages of bacterial solution required for concrete by forming various concrete cube samples having variations of bacterial solution viz. 15 ml, 30 ml, 45 ml, 60 ml and 75 ml. Further these various samples are tested under various laboratory methods viz. slump cone test, compressive strength testing machine, ultrasonic pulse velocity test, plate count cells and scanning electron microscopes thereby an optimum dosage required is computed. Bacterial concrete is found to be superior as compare to that of conventional concrete in all the aspects of durability. Among the different specimen incorporated it shows that bacterial concrete containing 45ml solution is the optimum dosage required, after which the strength found to be stable or decreased. LIST OF CONTENT CHAPTER CONTENT PAGE NO. NO. 1. Introduction 1.1 Background 1.2 Aim of the Project work 1.3 Future Scope of Investigation 2. Literature review 2.1 Summary of Literature review 3. Bacterial conditions, Cultural Programme& Material 3.1 Selection of Bacteria 3.2 Cultivation of Bacteria 3.2.1 Experimental Procedure for cultural growth of Bacteria 3.2.2 Safety measures for the Bacterial solution 3.3 Material 3.3.1 Cement 3.3.2 Sand 3.3.3 Coarse Aggregate 3.3.4 Cube Moulds 4. Experimental Methods and Test 4.1 Preparation of concrete mix and sample labeling 4.2 pH of Concrete 4.3 Methods of mixing of Bacterial Solution 4.4 Casting of cubes and Curing of Cubes for different specimens of bacterial concrete 4.5 Experimental tests on Bacterial Concrete 4.5.1 Slump Cone test 4.5.2 Compressive Strength test 4.5.3 Ultra-Sonic pulse velocity test 4.5.4 Plate Count method 4.5.5 Scanning Electron Microscope (SEM) 5. Experimental results & discussion 5.1Slump Cone test 5.2 Compressive Strength test 5.3 Ultra-Sonic pulse velocity test 5.4 Plate Count method 5.5Scanning Electron Microscope (SEM) 6. Conclusion 7. References LIST OF FIGURES Fig Description Page No. No. 1. Microphotograph of strains of Bacillus Subtilis 2. Bacterial solution in incubator 3. Cement 4. Sand 5. Coarse Aggregate 6. Cube Moulds 7. Sampling of Cubes 8. Mixing of Concrete 9. pH paper indicating the pH value of Concrete 10. Method Adopted before mixing the Bacterial solution in the Mixing water 11. Curing Tank of concrete cube 12. Slump Height 13. Slump Test Result 14. CTM Machine 15. Before and After Crushing of Cubes 16. Ultrasonic Pulse Velocity Machine 17. Plate Count Method Chapter 1 Introduction 1.1 Background Carbonate-producing bacteria have attracted lots of interest as a promising, natural, environmental friendly novel technique to improvement of concrete characteristics. Considerable research has been conducted on utilizing microbial-induced carbonate precipitation to mitigate several concrete problems such as crack repair(Van Tittelboom et al. 2010;Wiktor and Jonkers 2011), reduction and modification of porosity (Ghosh et al. 2005, 2009), and permeability(De Muynck et al. 2007a; Jonkers and Schlangen 2008;Nemati and Voordouw 2003). Furthermore, bacterial carbonate precipitation (bio deposition) has shown positive influences on compressive strength improvement of concrete (Bang et al. 2001;Ghosh et al. 2005, 2009; Jonkers and Schlangen 2008; Jonkers et al.2010; Reddy et al. 2010) and also, it also reduces water absorptionand carbonation of concrete as an alternative surface treatment(De Muynck et al. 2007a, b, 2008a, b).As part of metabolism, some bacteria produces enzyme urease whichcatalyzes the hydrolysis of urea to generate carbonate ions without an associated production of protons which leads to CaCO3 precipitation in presence of calcium ions (Chahal et al. 2012;Okwadha and Li 2011; Siddique and Chahal 2011). Therefore, bacteria cells not only provide a nucleation site for CaCO3 precipitation due to their negatively charged cell walls, but also create an alkaline environment inducing further growth of CaCO3 crystals (Ferris et al. 1987; Stocks-Fischer et al. 1999). One ml of urea is hydrolyzedintracellularly to 1 ml of ammonia and 1 ml of carbonate, which is presented in Eq. 1 (1). According to Eq. (2), carbonate hydrolyzes to ammonia and carbonic acid.Eqs. (3) and (4) demonstrate former products subsequently equilibrate in water to form bicarbonate, ammonium, and hydroxide ions. The latter causes pH increase resulting in the formation of carbonate ions [Eq. (5)], which in the presence of soluble calcium ions precipitate as CaCO3 [Eq. (6)]. Eq. (7) is the overall reaction, which demonstrates that ammonium and calcium carbonate are the products of added urea and calcium to the system (Siddique and Chahal 2011; Van Tittelboom et al. 2010). 𝐶𝑂(𝑁𝐻2) 2+𝐻2𝑂 → 𝑁𝐻2𝐶𝑂𝑂𝐻+𝑁𝐻3 …… (1) 𝑁𝐻 𝐶𝑂𝑂𝐻+ 𝐻 𝑂 → 𝑁𝐻 +𝐻 𝐶𝑂 ....… (2) 2 2 3 2 3 𝐻 𝐶𝑂 → 𝐻𝐶𝑂 +𝐻+. ..…. (3) 2 3 3 2𝑁𝐻 +2𝐻 𝑂 → 2𝑁𝐻 +2𝑂𝐻− …… (4) 3 2 4+ 𝐻𝐶𝑂 +𝐻+ +2𝑂𝐻− → 𝐶𝑂 +2𝐻 𝑂 ...…. (5) 3− 3 2− 2 𝐶𝑂 +𝐶𝑎2+ → 𝐶𝑎𝐶𝑂 ..….. (6) 3 2− 3 𝐶𝑂(𝑁𝐻 ) +2𝐻 𝑂+𝐶𝑎2+ → 2𝑁𝐻 +𝐶𝑎𝐶𝑂 …… (7) 2 2 2 4+ 3 Effect of the application of ureolytic bacteria such as Bacillus pasteurii [now reclassified as Sporosarcina pasteurii (Siddique and Chahal 2011), B. subtilis, and B. sphaericus on concrete characteristics has been extensively studied. Stocks-Fischer et al. observed CaCO3 crystals in sand specimens containing B. pasteurii cells accompanied with urea and CaCl2. Possible biochemical reactions in urea-CaCl2 medium to precipitate CaCO3 at the cell surface can be summarized as follows (Stocks-Fischer et al. 1999): 𝐶𝑎2+ +𝐶𝑒𝑙𝑙 → 𝐶𝑒𝑙𝑙−𝐶𝑎2 …… (1) 𝐶𝑙− +𝐻𝑁𝑂 +𝑁𝐻 → 𝑁𝐻 𝐶𝑙 + 𝐶𝑂 …… (2) 3− 3 4 3 2− 𝐶𝑒𝑙𝑙−𝐶𝑎2 + 𝐶𝑂 → 𝐶𝑒𝑙𝑙−𝐶𝑎𝐶𝑂 ↓ …… (3) 3 2− 3 Reddy et al. have reported the addition of B. subtilis bacteria increases the compressive strength of standard grade concrete up to about 15% at 28 days, and also shows a significant improvement in split tensile strength compared to conventional concrete (Reddy et al. 2010). Chahal et al. have prepared fly ash concrete specimens employing S. pasteurii, and attributed significant 28-day compressive strength increment of fly ash concrete to 2