scholarly journals Utilization of Bacillus Subtilis Bacteria for Improving Mechanical Properties of Concrete

2020 ◽  
Vol 1000 (1000) ◽  
Author(s):  
Sudipto Nath Priyom ◽  
Md. Moinul Islam ◽  
Wahhida Shumi
Keyword(s):  
Bacillus Subtilis ◽  
Ultrasonic Pulse Velocity ◽  
Ultrasonic Pulse ◽  
Pulse Velocity ◽  
Maintenance Cost ◽  
Concrete Technology ◽  
Conventional Concrete ◽  
Culture Density ◽  
Microbial Groups ◽  
Bacterial Concrete

Utilization of concrete as a building material is well-known worldwide and increasing continuously due to its sustainability, low maintenance cost, durability performance, etc. Ingredients of concrete, its constructional methodology, exposure conditions are moderating and improving day by day. However, this study covers a laboratory investigation of Bacterial Concrete. The bacterial concrete technology is based on the application of the mineral producing microbes. Some microbes like Bacillus subtilis which have the properties of bio-calcification can precipitate CaCO3 effectively inside concrete structures. This CaCO3 precipitation can fill the pores and therefore, the cracks internally and finally make the structure more compact. In this experimental study, Nutrient Broth (NB) media was employed for the growth and spore formation of Bacillus subtilis bacteria. Four different bacterial culture densities (0.107, 0.2, 0.637, and 1.221) were estimated at OD600 and directly added to concrete matrix maintaining previously fixed water to culture ratio (0.5:0.5). 100 mm cubical concrete specimens were cast, subjected to compressive and tensile strength tests for different curing ages and finally compared with Conventional Concrete (OD600=0). Significant increase in mechanical strengths was observed due to addition of Bacillus subtilis bacteria in concretes which have the culture density of 0.637. Soon cylindrical concrete specimens of 100 mm diameter and 200 mm height were prepared for Ultrasonic Pulse Velocity (UPV) analysis. The test results obtained from UPV analysis reveal that specimens prepared with culture density of 0.637 show higher pulse velocity than other microbial groups. Afterwards, this paper proposes a UPV vs. compressive strength relationship curve for different strengths of concrete.

Evaluation of the Mechanical Strength of a Concrete Modified with PET Fibers from Post-Consumer Bottles

2020 ◽  
Vol 862 ◽  
pp. 66-71
Author(s):  
Victor Hugo Blancas-Herrera ◽  
Wilfrido Martínez-Molina ◽  
Hugo Luis Chavez-Garcia ◽  
Jorge Alberto Pacheco-Segovia ◽  
Sandra del Carmen Argüello-Hernández ◽  
...  
Keyword(s):  
Electrical Resistivity ◽  
Mechanical Behavior ◽  
Ultrasonic Pulse Velocity ◽  
Ultrasonic Pulse ◽  
Pulse Velocity ◽  
Conventional Concrete ◽  
Pet Bottles ◽  
Concrete Mixtures ◽  
Hydraulic Concrete ◽  
Pet Fibers

The creation of sustainable hydraulic concrete from the use of waste materials, such as PET bottles, whose performance is better than the conventional concrete, has been a great challenge worldwide within the construction industry. This article shows a study on the application of PET fibers resulting from the recycling of post-consumer bottles, which will help increase their physical and mechanical behavior. Two concrete mixtures were made: a control mixture (M-C), with the proportions of a conventional concrete and a second mixture, adding 0.8% of PET fibers with respect to the cement mass (PR-0.8). Tests of electrical resistivity, ultrasonic pulse velocity, compressive strength, tensile strength and flexural strength were performed at the ages of 7 and 28 days. The results showed a slight improvement in the mechanical behavior of the PR-0.8 mixture, in contrast to the M-C mixture, given that a non-sudden failure occurs; while that the tests of electrical resistivity and pulse velocity indicate that the concrete produced is of good quality and durable.

scholarly journals MECHANICAL, THERMAL AND DURABLE PERFORMANCE OF WASTES SAWDUST AS COARSE AGGREGATE REPLACEMENT IN CONVENTIONAL CONCRETE

2018 ◽  
Vol 81 (1) ◽  
Author(s):  
Gassan Fahim Huseien ◽  
Ruhal Pervez Memon ◽  
Ziyad Kubba ◽  
Abdul Rahaman Mohd Sam ◽  
Mohammad Ali Asaad ◽  
...  
Keyword(s):  
Heat Transfer ◽  
Elevated Temperatures ◽  
Evaluation Process ◽  
Ultrasonic Pulse Velocity ◽  
Ultrasonic Pulse ◽  
Pulse Velocity ◽  
Conventional Concrete ◽  
Long Duration ◽  
Mechanical And Physical Properties

Wood yields a number of by-products and Sawdust is as useful as others. Sawdust is regarded as a waste material and is effectively utilised as sawdust concrete in the construction of buildings. It is capable to be utilised as light-weight concrete and holds the quality of long duration heat transfer. In this study, three different ratios (1:1, 1:2 and 1:3) volume mix proportions of cement to sawdust were adopted to make sawdust concrete. At varied intervals of 7, 28 and 56 days of air curing, thermal and mechanical properties like workability, density, elastic modulus, strength and heat transfer were probed of mentioned sawdust concrete proportions. The resistance to elevated temperatures was also evaluated after 28 days of age; weight loss, residual compressive strength, surface texture and ultrasonic pulse velocity were considered in evaluation process. The findings showed that increase in sawdust volume affected to decrease the workability, strength and elevated temperatures resistance. However, the concrete having higher proportion of sawdust performed competently and well in terms of thermal conductivity. Moreover, a decrease in the heat transfer of sawdust was also observed. Examining the all-embracing mechanical and physical properties, sawdust can be effectively utilised in the construction of buildings.

scholarly journals Behaviour of Incorporation of Bacteria in Concrete

2021 ◽  
Vol 889 (1) ◽  
pp. 012022
Author(s):  
Aditya Kumar Tiwary
Keyword(s):  
Flexural Strength ◽  
Healing Process ◽  
Ultrasonic Pulse Velocity ◽  
Ultrasonic Pulse ◽  
Pulse Velocity ◽  
Conventional Concrete ◽  
Concrete Crack ◽  
Micro Cracks ◽  
Enterobacter Species ◽  
Compressive Strength Of Concrete

Abstract The life of the healing in concrete is many years old and when the study was done on this, outcomes were coinciding with the auto-genus healing process which was capable to heal the micro cracks inside cementitious based materials and hereafter research led to the study of autonomous healing. In the autonomous healing process, the main aim was to fill the cracks and heal the fracture at the macro level. This was possible with the help of bacteria that were embedded in the cementitious based material with different technologies and methods. In this paper, Enterobacter species and Cohnii bacteria were incorporated into concrete. The behaviour of bacterial concrete was investigated in terms of compressive, tensile, flexural strength and ultrasonic pulse velocity. It observed that the compressive strength of concrete was increased by 11.5%, flexural strength increased by 11.9%, tensile strength increased by 12.8% with the replacement of Cohnii bacteria as compare to conventional concrete. These bacteria have been proved a positive approach to the healing process in cementitious based material. Also, the important criterion has been studied which is essential when dealing with the autonomous healing process. Both the bacteria generate the calcite that helps to fill the concrete crack and voids if water come in to contact.

scholarly journals DEVELOPMENT OF COMPRESSIVE STRENGTH AND ULTRASONIC PULSE VELOCITY RELATIONSHIP OF MICROBIAL CONCRETE USING BACILLUS SUBTILIS BACTERIA

2021 ◽  
Vol 9 (11) ◽  
pp. 412-421
Author(s):  
Mohammad Saiful Islam ◽  
◽  
Md. Saiful Islam ◽  
Keyword(s):  
Compressive Strength ◽  
Bacillus Subtilis ◽  
Bacterial Species ◽  
Essential Element ◽  
Ultrasonic Pulse Velocity ◽  
Ultrasonic Pulse ◽  
Pulse Velocity ◽  
Natural State ◽  
Plain Water ◽  
Bacterial Concentration

Concrete,a multiscale composite in its natural state, is an absolutely essential element of infrastructure throughout the world. Concrete is able to carry high compressive load but very weak in case of tensile forces, for which steel bars are embedded in the concrete.Again, cracks in concrete are unavoidable. Corrosive elements can go into cracks once theyve formed and consequently deterioration of the structural concrete starts with the corrosion of embedded steel. This leads to the strength reductionand durability curtailment of concrete. So, crack minimization in reinforced concrete is a must for both strength and durability aspect as well as for economic reasons as crack repair is a costly process. The goal of this study is to compare the performance of traditional and bacterial concrete and to find a link between compressive strength and bacterial culture concentration, as well as to determine the optimal bacterial concentration in concrete. 100 mm cubical sizeconcrete specimens were cast and cured for different ages in plain water to study the strength aspect and ultrasonic pulse velocity (UPV) analysis of concrete using Bacillus subtilis bacteria.With different bacterial concentrations of 2.12 x 108 cells/ml, 2.12 x 107 cells/ml, 3.25 x 108 cells/ml, 3.25 x 107 cells/ml, 6.39 x 108 cells/ml, 6.39 x 107 cells/ml, 7.91 x 108 cells/ml and 7.91 x 107 cells/mlconcrete specimens have been studied. From the investigation it is found that concrete specimens containing bacterial species shows better performance than conventional concrete due to calcite precipitation. Among them, concrete specimens of bacterial concentration 6.39 x 108 cells/ml of bacterial water shows better result against strength deterioration and UPV analysis.

Performance of Recycled Aggregate Concrete Made with Waste Refractory Brick

2021 ◽  
Vol 57 ◽  
pp. 99-113
Author(s):  
Mohammed Khattab ◽  
Samya Hachemi
Keyword(s):  
Coarse Aggregate ◽  
Physical And Mechanical Properties ◽  
Ultrasonic Pulse Velocity ◽  
Ultrasonic Pulse ◽  
Pulse Velocity ◽  
Recycled Aggregate Concrete ◽  
Recycled Aggregate ◽  
Recycled Aggregates ◽  
Conventional Concrete ◽  
Refractory Bricks

Concrete containing recycled aggregates have different properties from concrete containing natural aggregates. This work investigates, firstly, the possibility of using recycled refractory bricks (RBA) as coarse aggregate for concrete, and secondly, finds the ideal replacement percentage of natural coarse aggregate (NCA) by RBA. For this, an experimental study was carried out to assess the physical and mechanical properties of concrete produced with the partial and total replacement of NCA by RBA. Two types of RBA from two different sources were used, RBA-1 obtained from the grinding of new refractory bricks and RBA-2 obtained from refractory bricks used in the furnace recovered from the cement plant. For each type of RBA, two concretes with water/cement (w/c) ratios of 0.59 and 0.38 were tested. These concretes were evaluated by density, water porosity, ultrasonic pulse velocity (UPV) and compressive strength, and compared to those obtained on conventional concretes. The results obtained show that concrete can be manufactured using RBA. Concrete containing 20% ​​RBA shows good quality compared with conventional concrete.

scholarly journals Physical and Mechanical Characteristics of Sustainable Concrete Comprising Industrial Waste Materials as a Replacement of Conventional Aggregate

2021 ◽  
Vol 13 (8) ◽  
pp. 4306
Author(s):  
Fadi Althoey ◽  
Md. Akter Hosen
Keyword(s):  
Compressive Strength ◽  
Mechanical Characteristics ◽  
Ultrasonic Pulse Velocity ◽  
Ultrasonic Pulse ◽  
Pulse Velocity ◽  
Waste Materials ◽  
Partial Replacement ◽  
Fine Aggregate ◽  
Conventional Concrete ◽  
Sustainable Concrete

In a sustainable approach, it is essential to reduce waste materials for improving the urban environmental performance leads to development in the livable, sustainable, and greener city. In pursuit of this goal, iron lathe waste was used in this study as a replacement of fine aggregate to produce sustainable concrete. Iron lathe waste is generally a waste material from the lathe machine, which is abundantly available to an extent. These waste materials may lead to environmental and health concerns. Therefore, the main goal of this study is to experimentally examine the physio-mechanical characteristics of sustainable concrete incorporating lathe iron waste. The lathe iron waste dusts (LIWD) were used as a partial replacement of fine aggregate in different levels by weight (5%, 10%, 15%, and 20%) to fabricate the sustainable concrete. The mechanical and physical properties of sustainable concrete were investigated by conducting tests, such as workability, ultrasonic pulse velocity, compressive strength, splitting tensile strength, and flexural strength to investigate the properties of the alternative concrete comparing with that of conventional concrete. The experimental results showed that the LIWD significantly enhanced the tensile, flexural, and compressive strength of the concrete up to 13%, 19%, and 38%, respectively. Therefore, LIWD can potentially improve the serviceability of the structural elements.

An Application of Rice Husk Ash (RHA) and Calcium Carbonate (CaCo3) as Materal for Self-Healing Cement

2016 ◽  
Vol 673 ◽  
pp. 3-12
Author(s):  
Januarti Jaya Ekaputri ◽  
Fahmi Firdaus Alrizal ◽  
Iqbal Husein ◽  
Triwulan ◽  
Mohd Mustafa Al Bakri Abdullah
Keyword(s):  
Calcium Carbonate ◽  
Rice Husk ◽  
Rice Husk Ash ◽  
Healing Process ◽  
Crack Depth ◽  
Ultrasonic Pulse Velocity ◽  
Ultrasonic Pulse ◽  
Pulse Velocity ◽  
Self Healing ◽  
Concrete Technology

Self-healing cement is a novel topic in concrete technology. Concrete is created to have its own ability to heal cracks. Crack closure is due to the material deposition of the gap so causing the crack closed. Materials used in this paper is mortar composition with ordinary portland cement replaced by calcium carbonate (CaCO3) and rice husk ash. There are three testing presented in this paper. The first is compressive test to determine the compression applied to mortar for initial cracks. The second is an ultrasonic pulse velocity (UPV) test to observe the depth of cracks and density of each composition. The third is macroscopic investigation to observe cracks wide in each mixture. The maximum compressive strength of 22.46 MPa shown by specimens made with 10% rice husk ash and 10% calcium carbonate cement. By the end of healing process, it reached 23.18 MPa. It was also shown that in crack depth decreased from 38 mm to 16 mm. From this analysis, it can be concluded that rice husk ash (RHA) and calcium carbonate (CaCO3) can be utilized as self-healing concrete materials.

PENGKAJIAN KEKUATAN BETON STRUKTUR JEMBATAN PASCA KEBAKARAN

2013 ◽  
Vol 12 (3) ◽  
Author(s):  
Sudarmadi Sudarmadi
Keyword(s):  
Compressive Strength ◽  
Concrete Strength ◽  
Ultrasonic Pulse Velocity ◽  
Ultrasonic Pulse ◽  
Pulse Velocity ◽  
Test Results ◽  
Concrete Compressive Strength ◽  
Strength Assessment ◽  
Concrete Testing

In this paper a case study about concrete strength assessment of bridge structure experiencing fire is discussed. Assessment methods include activities of visual inspection, concrete testing by Hammer Test, Ultrasonic Pulse Velocity Test, and Core Test. Then, test results are compared with the requirement of RSNI T-12-2004. Test results show that surface concrete at the location of fire deteriorates so that its quality is decreased into the category of Very Poor with ultrasonic pulse velocity ranges between 1,14 – 1,74 km/s. From test results also it can be known that concrete compressive strength of inner part of bridge pier ranges about 267 – 274 kg/cm2 and concrete compressive strength of beam and plate experiencing fire directly is about 173 kg/cm2 and 159 kg/cm2. It can be concluded that surface concrete strength at the location of fire does not meet the requirement of RSNI T-12-2004. So, repair on surface concrete of pier, beam, and plate at the location of fire is required.

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