Study on Optimal Mix Proportion of PVA-ECC Based on Strength-Deformation-AHP

2014 ◽  
Vol 1065-1069 ◽  
pp. 1939-1944
Author(s):  
Yu Guo Zheng ◽  
Wei Nan Wang ◽  
Yuan Dong Cui ◽  
Si Min Liu ◽  
Yong Zhang

Considering the essential influencing factors for the mechanical properties of the engineered cementitious composite (ECC), the polyvinyl alcohol (PVA) fiber was used and a batch of cube specimens and thin plate specimens of PVA-ECC were manufactured based on the variation of water cement ratio, amount of fly ash and amount of water reducer. The compressive strength test for the PVA-ECC cube specimens and the flexural strength test for the PVA-ECC thin plate specimens were conducted. A practical decision-making frame based on the Analytic Hierarchy Process (AHP) method was proposed to solve the problem of the optimal mix proportion of PVA-ECC, which can take into account the compressive strength, the flexural strength and the corresponding deformation capacity together.

2019 ◽  
Vol 8 (3) ◽  
pp. 7736-7739 ◽  

This paper studies the effect of incorporating metakaolin on the mechanical properties of high grade concrete. Three different metakaolins calcined at different temperature and durations were used to make concrete specimens. Three different concrete mixtures were characterized using 20% metakaolin in place of cement. A normal concrete mix was also made for comparison purpose. The compressive strength test, split tensile test and flexural strength tests were conducted on the specimens. The compressive strength test results showed that all the metakaolin incorporated concrete specimens exhibited higher compressive strength and performed better than normal concrete at all the days of curing. The rate of strength development of all the mixes was also studied. The study revealed that all the three different metakaolin incorporated mixtures had different rate of strength development for all the days of hydration (3, 7,14, 28, 56 and 90), indicating that all the metakaolins possessed different rate of pozzolanic reactivity. Further, from the analysis of the test results, it was concluded that the variation in the rate of strength development is due to the differences in the temperature and duration at which they were manufactured. The results of split tensile strength test and the flexural strength test conducted on the specimens, supported the conclusions drawn from the results of compressive strength test. The paper also discusses, the rate of development of compressive strength and the pozzolanic behaviour of the metakaolins in light of their parameters of calcination and physical properties such as amorphousness and particle size. This paper has been written with a view to make the potential of metakaolin available to the construction industry at large


Author(s):  
S. B. Kandekar ◽  
◽  
S. K. Wakchaure ◽  

Materials are the most important component of building construction. The demands of construction material are increasing day by day significantly. This demand is increasing the material prices and scarcity of material in construction industry. To achieve economical and eco-friendly criteria naturally occurring material is selected. Clay is a natural material and it can be available easily. This paper interprets the experimental investigation on strength of concrete using clay as a partial replacement to binder content (cement) in concrete. The replacement percentages are grouped as 0%, 10%, 20%, 30%, 40% of clay and 5% of hydrated lime with cement in each series in M25 grade of concrete. To achieve the pozzolanic property of clay hydrated lime was added. Different tests are performed to determine the optimum percentage of clay as a replacement for binder content (cement) in concrete. The Compressive strength test, split tensile strength test and flexural strength test were performed on the specimens. Total 90 cubes of size 150 mm were prepared for compressive strength test, 30 cylinders of 150 mm diameter and 300 mm height were prepared for split tensile strength test and 30 beams of size 150 mm x 150 mm x 1000 mm were prepared to carry out the flexural strength test. The results are compared to find the ideal proportion of clay as a replacement for cement. It is found that 10% replacement with 5% hydrated lime gives satisfactory results.


2020 ◽  
Vol 5 (1) ◽  
pp. 1-10
Author(s):  
E. A Oluwasola ◽  
A Afolayan ◽  
O. O. Ipindola ◽  
M. O Popoola ◽  
A. O Oginni

Aggregates constitute more than 90% of concrete and significantly determine the strength of concrete. In this study, the shape characteristics such as flakiness and elongation were determined using elongation and thickness gauge. The aggregate used for the study is granite. Aggregate crushing value and aggregate impact value tests were performed on the aggregate while slump test, water absorption test, compressive strength test and flexural strength test were carried out on concrete. A total of one hundred and thirty-two concrete cubes were produced using 1:2:4 and 1:3:6 mix each for the compressive strength test and forty-eight reinforced concrete beams were produced for flexural strength test. The slump for all the samples tested was examined to be true. The compressive strength of the concrete cube was greatly affected by the shape of aggregate used and it was noted that; for lower percentage of flaky and elongated aggregate the compressive strength is moderately high compared to when the percentage is high. The highest obtained compressive strength, 15N/mm2 is in compliance with the concrete compressive strength of normal 1:2:4 mix as stipulated in ASTM C109, Also, with 30% of elongated aggregate and 30% of flaky, the flexural strength of 7.03 N/mm2 was obtained. This shows that aggregate shape is a very important property of coarse aggregate that must be put into consideration in production of quality concrete for construction works.


2018 ◽  
Vol 7 (2.24) ◽  
pp. 552
Author(s):  
Jeganmurugan P ◽  
Rakesh Senthil Kumar G V ◽  
Sivasharmina M ◽  
Sowmiya S ◽  
Vasanthan M

Reactive powder concrete (RPC) is ultra high strength with advanced mechanical properties. Reactive powder concrete is a concrete without coarse aggregate, contains cement, silica fume, quartz sand, quartz powder, super plasticizer, steel fibre and polypropylene fibre with very low water cement ratio under normal curing condition. RPC has been produce with high compressive strength ranging from upto 800 MPa with high flexural strength up to 50 MPa and in some cases provided with absences of steel reinforcement. Mix proportions of RPC were found by trial and error method, the concrete cubes of size 100mmx100mmx100mm were cast for find compressive strength of NRPC at 7days. Concrete cubes and cylinders of sizes 100mmx100mmx100mm and 100mmx150mm have to be cast for finding compressive strength and split tensile strength at 28 days. Flexural strength of NRPC and MRPC will be find out by casting prism of size 500mmx 100mmx 100 mm. The optimum mix proportion has to be finalized by comparing the results of all concrete specimens. Compressive strength test results shows that addition of silica fume upto 0.22% will increase the compressive strength of reactive powder concrete.   


Author(s):  
Vrushabh K. Hulle

Abstract: Concrete consisting of cement, water, fine and coarse aggregates are widely used in civil engineering constructions. Though making concrete is convenient and inexpensive, its brittle behavior upon tensile loading is one of its undesirable characteristics so that leads to the development of fiber reinforced concrete or engineered cementitious composites to improve this deficient. The Flexural strength of PVA (polyvinyl alcohol) FRC (fiber reinforced concrete) can be 150-200% greater than for normal concrete. According to Structural designers the damage tolerance and inherent tight crack width control of PVA FRC is found to be impressive in recent full-scale structural applications. If proper volume fractions are used the compressive strength PVA FRC can be similar to that of conventional concrete. The aim of this research work is to study compressive and tensile strength of FRC consisting PVA fiber & glass powder and studying the effect of glass powder in it. This research also gives rough idea on crack resistance capacity of FRC. In this paper we studied and provided detailed review on properties of PVA FRC with glass powder and experimentally identified the best ECC mix by analyzing the compressive & the flexural strength at different ratios like 0.5%, 1%, 1.5% of PVA fiber of total dry mix weight and in each case 15% of fine aggregate was replaced by glass powder. By conducting the compressive strength test and flexural strength test the maximum result we get at 28 days is 28.38Mpa and 8.95Mpa respectively which is more durable as compared to conventional concrete by IS 516:1959. So by analysis of results it can be seen that 1% mix is found to be optimum in all aspects. Keywords: PVA FRC, Polyvinyl Alcohol, Fibre Reinforced Concrete, Glass Powder.


2021 ◽  
Vol 3 (1) ◽  
pp. 33-40
Author(s):  
Lantif Anggrahita Pratama ◽  
Ahmad Hakam Rifqi ◽  
Muhtarom Riyadi

Concrete is the most important part of a construction building. The purpose of this study was to examine how the comparison of physical and mechanical properties and optimum levels of the addition of straight tie wire as an added material with a water-cement ratio of 0.4. The percentage of addition of straight tie wire: 0%, 0.5%, 0.75%, 1.0%, of the total weight of the specimen with a tie-wire length of 8 cm. The test specimens for compressive strength, modulus of elasticity, and split tensile are in the form of a cylinder with a diameter of 15 cm and a height of 30 cm, and the specimen for flexural strength is a block with a length of 50 cm, a width of 10 cm and a height of 10 cm. The results show that the maximum compressive strength test on tie wire occurred at a percentage of 0.75% of 16.56 MPa. The maximum modulus of elasticity in tie wire occurred at a percentage of 0.75% of 15184.56 MPa. The maximum split tensile strength of tie wire occurred in a percentage of 0.75% of 1.165 MPa, and the maximum flexural strength of tie wire occurs at a percentage of 0.75% of 1.950 MPa. The research results concluded that the addition of a straight tie-wire to the concrete mixture could increase the compressive strength, split tensile strength, tensile strength, and elastic modulus of concrete.


TAMAN VOKASI ◽  
2019 ◽  
Vol 7 (2) ◽  
pp. 182
Author(s):  
Agus Priyanto

Abstracts. The supply of wood that is quite durable and of high quality has not been able to meet the needs of building construction at the present time, especially in the future. Sengon wood (Paraserianthes falcataria) is a fast-growing type of plant that has a large increase (volume of wood per hectare per year) which is around 28 - 48 m3 / ha / year. To fulfill various human objectives, the majority of Sengon wood can be collected from the age of 6 years. With the use of lamination technology, wood remnants can be utilized to be made into wooden blocks of various sizes and various shapes. Lamination can make the strength of Sengon wood higher than solid wood beams.The test is carried out by physical and mechanical tests as well as the Sengon wood laminated sliding block test. In testing physical and mechanical properties based on ISO 1975 regulations. Testing of physical properties of Sengon wood includes wood density test and moisture content test. Testing the mechanical properties of Sengon wood includes fiber parallel compressive strength test, fiber perpendicular compressive strength test, tensile strength test, shear strength test and flexural strength test. Testing of Sengon wood laminated sliding blocks to determine the strength of lamination has a variation of 30 MDGL, 40 MDGL and 50 MDGL slurry adhesives with 3 replications of each shear test.The average density of Sengon wood is 0.315 t / m3 and the average moisture content of Sengon wood is 13.539%. The average compressive strength of fibers is 26.85 MPa and the compressive strength of fibers is 9.62 MPa. The average tensile strength of Sengon wood is 61.48 MPa and the average shear strength of Sengon wood is 5.31 MPa. In testing the flexural strength of Sengon wood an average of 43.18 MPa. Testing of Sengon wood laminate sliding block for 30 / MDGL obtained an average of 0.05 kg / mm2. In the shear block 40 / MDGL obtained an average shear strength of 0.02 kg / mm2. For the 50 / MDGL laminate shear block an average shear strength of 0.08 kg / mm2 was obtained.


2019 ◽  
Vol 258 ◽  
pp. 01024 ◽  
Author(s):  
Teddy Tambunan ◽  
Mohd. Irwan Juki ◽  
Norzila Othman

In construction, concrete durability is an important material globally used in engineering, material of which can be applied in the fields of specialized marine construction. The ingress of chloride into concrete causes deterioration in the concrete due to the reinforcement corrosion. Adding bacteria into concrete can improve material properties and increase durability with mechanism resist chloride ingressed in the concrete . Ingress of Chloride into the concrete of bacteria is particularly suited for applications of chloride ion penetration in concrete. The objective of the research is to determine the effect of adding bacteria into the concrete properties. The bacteria used in this research is locally isolated and enriched to the suite with the concrete environment. The type of the bacteria used is identified as Sulphate Reduction Bacteria (SRB). The SRB added into the concrete mix with concentrations of 3%, 5% and 7%. Whereas, concentration of bacteria water of cement is 0.5. The mechanical properties test conducted with 28th, 56th, 90th, 180th and 360th day of curing period. The test was using cyclic wetting and drying to study the exposure to chloride condition, such as compressive strength, tensile strength and flexural test. Cubes in the size of 150 mm × 150 mm × 150 mm were prepared for compressive strength test and cylinder 150 mm × 300 mm were prepared for the tensile strength test. The flexural strength test was on the prism in the size of 100 mm × 100 mm × 500 mm. The result of compressive strength test shows, that gave significant strength of 66.3 MPa on the 360th day. The tensile strength and flexural strength have a similar trend as compressive strength results, where both results were optimum . The tensile strength test shows that 4.52 MPa tends to control 3.96 MPa. The result of flexural strength test was 8.23 MPa for compared to control of 5.99 MPa. The overall results of the bacteria indicate promising outcome and further study on chloride condition capability is encouraging.


2019 ◽  
Vol 3 (3) ◽  
pp. 55-68
Author(s):  
Ali Ajwad ◽  
Abdullah ◽  
Muhammad Usman ◽  
Shakir Ahmad ◽  
Usman Ilyas ◽  
...  

In this research, fine and coarse aggregates present in the concrete were replaced with steel dust and shred-like steel fibres respectively in different ratios and the effect of their replacement on the properties of concrete was studied. Eight batches of concrete were mixed, each with the mix proportion of 1:2:4 and water- cement ratio of 0.52. Batch A was of normal concrete. In batches B, C, and D, 5%, 10%, and 15% of sand was replaced with steel dust, respectively. In batches, E, F, and G, 2%, 5%, and 8% of coarse aggregates were replaced with steel fibres. In the last batch H, 5% of sand and 5% of coarse aggregates were replaced with steel fines and steel fibres, respectively. British as well as American standards were followed during the research. Slump test was performed in the fresh state of each mix to find the effect of these replacements on its workability. 12 cubes of 150mm × 150mm × 150mm for compressive strength test and 12 cylinders of 150mm diameter and 300mm height for tensile strength test were made for each batch to check their strength after every 3, 7, 14, and 28 days. It was found that the workability of fresh concrete decreases while the density of fresh as well as hardened concrete increases with these replacements. They also result in an increase in initial compressive strength and a decrease in final compressive strength as compared to those of normal concrete. As far as tensile strength is concerned, an increase in initial as well as final strength was observed.


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