scholarly journals The Effect of Microbes and Fly Ash to Improve Concrete Performance

2021 ◽  
Vol 4 (2) ◽  
pp. 60
Author(s):  
Adlizie Rifkianda Muhammad ◽  
Januarti Jaya Ekaputri ◽  
Makno Basoeki

This paper presents the application of�fly ash�combining with microbes in concrete to reduce cement content.�A class F fly ash as cement replacementwas applied with ratios of 20%, 30%, 40%, and 50% to reduce hydration heat. Microbes from bacterial consortium were applied to as the filler to increase concrete compressive strength. The concrete mix design from SNI 03�2834�2000 was applied for a compressive strength target of 30 MPa. The mechanical test was carried out consisting compressive and tensile test.�Concrete�workability�and the heat hydration measurement were performed for fresh concrete.�The results showed that the maximum strength of 45.10 MPa was obtained from specimens with 30% fly ash content.�Application of microbes associated with�fly ash content of 40% showed the maximum strength of 48.47 MPa.�It was found that the tensile strength also increased with the application of�fly ash�and microbes.�Hydration temperature of concrete decreased with the increase of�the ash�content.�This proves that the application of�fly ash�and microbes in concrete can reduce the cement as well as increasing the concrete performance.

2016 ◽  
Vol 249 ◽  
pp. 21-27 ◽  
Author(s):  
Adam Hubáček ◽  
Rudolf Hela

The article deals with theme of high fly ash content concretes intended for long life constructions. Considering the still growing consumption of fly ash in construction concretes it is a live theme in the Czech Republic and abroad as well. The emphasis will be laid namely on characteristics and requirements for fresh concrete intended for construction of these specific concrete constructions. They are for instance waterproof constructions, tunnel linings, concretes for bridge and road constructions etc. Also the hardened concrete properties like compressive strength, resistance to pressure water, durability and further necessary parameters for obtainment of required properties of these concretes will be monitored.


2018 ◽  
Vol 6 (2) ◽  
pp. 114-123
Author(s):  
Redaksi Tim Jurnal

With improve the quality of concrete is by using the addition of admixture. By adding admixture Silica fume and superplasticizer is expected to improve concrete quality in concrete using fly ash and bottom ash. The main objective of this research is to know the value of concrete compressive strength, slump test value, fresh concrete temperature and setting time in concrete using fly ash and bottom ash by 0%, 5%, 10%, 15%, 20% and 25% by weight of cement, with variations of silica fume 0%, 2%, 4%, 6 %, 8%, 10% of the weight of cement that has been reduced by the weight of fly ash and bottom ash and added with superplasticizer of 2% of the water requirement. The planned concrete quality was 41.7 MPa at 28 days, with the sample tested at age 7, 14, 28 days. Based on the results of the highest concrete compressive strength test for fly ash concrete (fly ash) is found in FA mixture variation 10%, SP 4%, SF 2% that is equal to 56,16 MPa. And for mixed bottom ash the highest compressive strength on mixed variation of BA 5%, SF 2%, SP 2% is equal to 49,82 MPa. Fresh concrete temperature variation of FA mixture 5%, SF 2%, SP 2% and BA 5%, SF 2%, SP 2% rose one degree from normal concrete temperature. Setting time generated on mixed concrete FA 5%, SF 2%, SP 2% has the fastest initial time setting ie 251 minutes of all variations of concrete mix.


2015 ◽  
Vol 804 ◽  
pp. 129-132
Author(s):  
Sumrerng Rukzon ◽  
Prinya Chindaprasirt

This research studies the potential for using waste ash from industrial and agricultural by-products as a pozzolanic material. Classified fly ash (FA) and ground rice husk ash (RA) were the materials used. Water requirement, compressive strength and porosity of cement mortar were investigated. Test results indicated that FA and RA (waste ash) have a high potential to be used as a good pozzolanic material. The water requirement of mortar mix decreases with the increases in fly ash content. For ground rice husk ash (RA), the water requirement of mortar mix increases with the increases in rice husk ash content. In addition, the reduction in porosity was associated with the increase in compressive strength.


2018 ◽  
Vol 4 (4) ◽  
pp. 54
Author(s):  
Iis Nurjamilah ◽  
Abinhot Sihotang

ABSTRAKKajian karakteristik beton memadat sendiri yang menggunakan serat ijuk merupakan sebuah kajian yang dilakukan untuk mengetahui pengaruh penambahan serat ijuk terhadap karakteristik beton memadat sendiri (SCC). Beton memadat sendiri yang menggunakan serat ijuk (PFSCC) didesain memiliki campuran yang encer, bermutu tinggi (= 40 MPa) dan memiliki persentase kekuatan lentur yang lebih baik. PFSCC  didapatkan dari hasil pencampuran antara semen sebanyak 85%, fly ash 15%, superplastizicer 1,5%, serat ijuk 0%, 0,5%; 1%; 1,5%; 2% dan 3% dari berat binder (semen + fly ash), kadar air 190 kg/m3, agregat kasar 552,47 kg/m3 dan pasir 1.063 kg/m3. Semakin banyak persentase penambahan serat ijuk ke dalam campuran berdampak terhadap menurunnya workability beton segar. Penambahan serat ijuk yang paling baik adalah sebanyak 1%, penambahan tersebut dapat meningkatkan kekuatan tekan beton sebesar 13% dan lentur sebesar 1,8%.Kata kunci: beton memadat sendiri (SCC), beton berserat, beton memadat sendiri yang menggunakan serat ijuk (PFSCC), serat ijuk ABSTRACTThe study of characteristics self compacting concrete using palm fibers is a study conducted to determine the effect of adding palm fibers to characteristics of self compacting concrete (SCC). palm fibers self compacting concrete (PFSCC) is designed to have a dilute mixture, high strength (= 40 MPa), and have better precentage flexural strength. PFSCC was obtained from mixing of 85% cement, 15% fly ash, 1.5% superplastizicer, 0%, 0.5%, 1%, 1.5%, 2% and 3% palm fibers from the weight of binder  (cement + fly ash), water content 190 kg/m3, coarse aggregate 552.47 kg/m3 and sand 1,063 kg/m3. The more persentage palm fibers content added to the mixture makes workability of fresh concrete decreases. The best addition of palm fiber is 1%, this addition can increases the compressive strength 13% and flexural strength 1.8%.Keywords: self compacting concrete (SCC), fiber concrete, Palm fiber self compacting concrete (PFSCC), palm fiber


2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Michał Piotr Musiał ◽  
Filip Grzymski ◽  
Tomasz Trapko

AbstractThis paper presents experimental research on expanded clay aggregate concrete. The aim of the investigations was to determine if the pre-wetting of expanded clay aggregate has an effect on the freeze-thaw durability of the expanded clay aggregate concrete. Five concrete series based on the same concrete mix design were made and tested. The degree of pre-wetting of the aggregate was varied: dry aggregate was used in the first series, aggregate with a moisture content of 10% was used in series IA and IB and aggregate with a moisture content of 25% was used in series IIA and IIB. Also the approach to the production process was varied: in series A the water contained in the aggregate was taken into account in the global water-cement ratio (consequently a reduced amount of water was added to the mix), whereas in series B the nominal amount of water was added to the mix (as in the case of dry aggregate). The freeze-thaw resistance criterion was based on the assessment of the decrease of compressive strength and increase in weight loss after exposure to freeze-thaw cycles. The expanded clay aggregate concrete's strength and mass decrements caused by freeze-thaw cycling were used as the measure of its freeze-thaw resistance. The investigations have shown that the pre-wetting of expanded clay aggregate has an effect on the freeze-thaw durability of the expanded clay aggregate concrete. The differences of concrete compressive strength decrease related to freeze-thaw durability may be 2 to 5 times greater when inadequate method of calculating mixing water for concrete is used.


2016 ◽  
Vol 7 (5) ◽  
pp. 546-550
Author(s):  
Aurelijus Daugėla ◽  
Džigita Nagrockienė ◽  
Laurynas Zarauskas

Cement as the binding agent in the production of concrete can be replaced with active mineral admixtures. Biofuel combustion fly ash is one of such admixtures. Materials used for the study: Portland cement CEM I 42.5 R, sand of 0/4 fraction, gravel of 4/16 fraction, biofuel fly ash, superplasticizer, water. Six compositions of concrete were designed by replacing 0%, 5%, 10%, 15% 20%, and 25% of cement with biofuel fly ash. The article analyses the effect of biofuel fly ash content on the properties of concrete. The tests revealed that the increase of biofuel fly ash content up to 20% increases concrete density and compressive strength after 7 and 28 days of curing and decreases water absorption, with corrected water content by using plasticizing admixture. It was found that concrete where 20% of cement is replaced by biofuel ash has higher frost resistance.


2020 ◽  
Vol 20 (01) ◽  
pp. 61-68
Author(s):  
Siska Apriwelni ◽  
Nugraha Bintang Wirawan

(ID) Penelitian ini membahas pengaruh kuat tekan beton mutu tinggi dengan memanfaatkan limbah fly ash dan limbah kaca. Tujuan dari penelitian ini untuk mengetahui kuat tekan beton pada masing-masing variasi, mengetahui persentase campuran beton untuk menghasilkan kuat tekan maksimum, dan mengetahui apakah fly ash dan serbuk kaca efektif digunakan secara bersamaan sebagai bahan campuran beton. Komposisi fly ash terdiri dari 5 variasi yaitu persentase 0%, 5%, 10%, 15%, dan 20%. Sedangkan untuk komposisi serbuk kaca terdiri dari 2 variasi yaitu persentase 5% dan 10%. Jumlah benda uji 30 buah silinder berukuran diameter 15 cm dan tinggi 30 cm dengan 3 benda uji untuk setiap variasi. Perencanaan campuran beton menggunakan SNI 03-2834-2000 yang dimodifikasi. Pengujian kuat tekan diuji pada umur beton 28 hari. Beton dengan fly ash 0% dan serbuk kaca 10% memiliki kuat tekan paling tinggi dibandingkan dengan beton dengan tambahan fly ash, yaitu 46,77%. Selain itu, dapat disimpulkan bahwa semakin bertambahnya jumlah persentase serbuk kaca yang digunakan menunjukkan bahwa kuat tekan beton semakin bertambah juga. Penambahan fly ash pada campuran beton mempengaruhi kuat tekan beton yang dihasilkan. Pada variasi fly ash 0% memiliki kuat tekan tertinggi baik pada saat campuran serbuk kaca 5%dan 10%. Variasi fly ash 15% adalah kondisi optimum campuran beton dengan kuat tekan beton yaitu 43,31 Mpa. Kedua limbah ini dapat dikombinasikan dan dimanfaatkan dengan baik dan digunakan dalam pembuatan beton mutu tinggi. (EN) This study discusses the effect of high quality concrete by utilizing fly ash and glass waste. The purpose of this study is to determine the compressive strength of concrete in each variation, to determine the contribution of concrete to produce compressive strength, and to find out that fly ash and glass powder are effectively used in full as a concrete admixture. Fly ash composition consists of 5 variations, namely the percentage of 0%, 5%, 10%, 15%, and 20%. While for the composition of glass powder consists of 2 variations, namely the percentage of 5% and 10%. The number of specimens is 30 cylinders with a diameter of 15 cm and a height of 30 cm with 3 specimens for each variation. Concrete mixture planning using SNI 03-2834-2000 was developed. Compressive strength testing on concrete age 28 days. Concrete with 0% fly ash and 10% glass powder have the highest compressive strength compared to concrete with additional fly ash, which is 46.77%. In addition, it can increase the amount of glass powder addition that is used to show the concrete compressive strength is increasing as well. The addition of fly ash in the concrete mixture has an effect on the compressive strength of the concrete produced. In the variation of 0% fly ash has the highest compressive strength when the glass powder mixture of 5% and 10%. The 15% fly ash variation is the optimal concrete mixture with compressive strength of 43.31 MPa. These two wastes can be combined and utilized properly and are used in making high quality concrete.  


2019 ◽  
Vol 967 ◽  
pp. 205-213
Author(s):  
Faiz U.A. Shaikh ◽  
Anwar Hosan

This paper presents the effect of nanosilica (NS) on compressive strength and microstructure of cement paste containing high volume slag and high volume slag-fly ash blend as partial replacement of ordinary Portland cement (OPC). Results show that high volume slag (HVS) cement paste containing 60% slag exhibited about 4% higher compressive strength than control cement paste, while the HVS cement paste containing 70% slag maintained the similar compressive strength to control cement paste. However, about 9% and 37% reduction in compressive strength in HVS cement pastes is observed due to use of 80% and 90% slag, respectively. The high volume slag-fly ash (HVSFA) cement pastes containing total slag and fly ash content of 60% exhibited about 5%-16% higher compressive strength than control cement paste. However, significant reduction in compressive strength is observed in higher slag-fly ash blends with increasing in fly ash contents. Results also show that the addition of 1-4% NS improves the compressive strength of HVS cement paste containing 70% slag by about 9-24%. However, at higher slag contents of 80% and 90% this improvement is even higher e.g. 11-29% and 17-41%, respectively. The NS addition also improves the compressive strength by about 1-59% and 5-21% in high volume slag-fly ash cement pastes containing 21% fly ash+49%slag and 24% fly ash+56%slag, respectively. The thermogravimetric analysis (TGA) results confirm the reduction of calcium hydroxide (CH) in HVS/HVSFA pastes containing NS indicating the formation of additional calcium silicate hydrate (CSH) gels in the system. By combining slag, fly ash and NS in high volumes e.g. 70-80%, the carbon footprint of cement paste is reduced by 66-76% while maintains the similar compressive strength of control cement paste. Keywords: high volume slag, nanosilica, compressive strength, TGA, high volume slag-fly ash blend, CO2 emission.


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