scholarly journals Effects of nanosilica to improve the mechanical, electrical and durability properties of fiber-reinforced high-volume processed sugarcane bagasse ash cement mortar

Author(s):  
Ramasamy Gopalakrishnan ◽  
RAVI KAVERI ◽  
A JohnKirubahar

Abstract Nanosilica (NS) has attracted wide variety of usage as cement ingredients. While many other studies have focused on early cement hydration and hardening properties, there is less data available on the impact of NS on the behavior of fiber-reinforced high-volume sugarcane bagasse cement mortar (HVSCBAM). The effects of NS on the fiber-reinforced durability of HVSCBAM, having the properties of sugarcane bagasse ash/binder in an average of 50% by weight, have been presented in detail in this study. Four NS/binder weight ratio dosages of 0%, 0.5%, 1.0% and 1.5% of and another four total PVA fiber/volume ratio dosages of 0%, 0.2%, 0.5% and 1.0% were used. Compared to 0.2-1 vol.% of PVA fiber–reinforced HVSCBAM, the 1.5 wt.% of NS would enhance the compressive strength further. Various reports on mineralogy and microstructure have demonstrated that NS facilitates fiber/matrix bonding. These conclusions provide an insight into the pozzolanic materials of cement that are used in a large volume in the designs and applications of nanoparticles.

Author(s):  
Sujata Subedi ◽  
Gabriel A. Arce ◽  
Marwa M. Hassan ◽  
Michele Barbato ◽  
Louay N. Mohammad

The use of raw sugarcane bagasse ash (SCBA) as sand replacement in the production of engineered cementitious composites (ECCs) can improve its cost-effectiveness and practicality. A recent study by the authors showed that the use of raw SCBA as a replacement to sand in ECC mixtures substantially enhances the tensile ductility and provides mild improvements in tensile strength; however, it also indicated a need to further elucidate the mechanisms producing such improvements. Therefore, the present study examined the effects of raw SCBA as a sand replacement in ECC’s fundamental fiber-bridging relationship, [Formula: see text], through single crack tensile test (SCTT) using 1% polyvinyl alcohol (PVA) fiber volume fraction. The PVA fiber volume fraction was reduced from 1.5% in the previous study to 1% in this study to ensure that a single crack was produced, which is a necessary condition to obtain the fundamental [Formula: see text] relationship. A total of five mixtures were evaluated at different replacement levels of sand with raw SCBA (i.e., 0%, 25%, 50%, 75%, and 100%). SCTT results revealed that raw SCBA produced minor effects on the fiber-bridging capacity but significantly increased the complementary energy ( [Formula: see text]). A positive correlation was observed between the pseudo strain-hardening (PSH) strength index and raw SCBA content. Since the PSH strength index was higher than the recommended value (i.e., 1.3) for robust PSH behavior, it was concluded that the main factor contributing to tensile ductility enhancements was the increase in the PSH energy index resulting from the notable increase of [Formula: see text] and potential decrease in matrix fracture toughness.


2015 ◽  
Vol 744-746 ◽  
pp. 1422-1426
Author(s):  
Jun Su ◽  
Jian Ping Liu ◽  
Ming Chen

In order to study the flexural toughness of PVA fiber reinforced concrete, employ the volume mixing ratio is 0.2%, 0.1%, 0.08%, polyvinyl alcohol (PVA) will be mixed with ordinary C40 concrete to form PVA fibers reinforced concrete. Its flexural toughness properties were tested and the load-deflection curve of all beams is obtained. Based on the ASTM method, the flexural toughness of PVA fiber reinforced concrete is analyzed. The experimental results indicate that the PVA fiber can improve the flexural toughness and the deformation ability of concrete beams remarkably. When the fiber volume ratio is 0.1%, the flexural toughness index I5 and I10 of concrete with PVA fiber are 3.73 and 6.23 times higher than that of the plain concrete respectively. The failure mode of PVA fiber concrete is changed from brittle to ductile fracture.


2015 ◽  
Vol 668 ◽  
pp. 367-374
Author(s):  
J.L. Rodríguez Bucio ◽  
José Luis Reyes-Araiza ◽  
Elia Mercedes Alonso Guzmán ◽  
Alejandro Manzano-Ramirez ◽  
R. Ramírez-Jiménez ◽  
...  

Since the construction industry is responsible for 30% of the CO2 emissions, one way to reduce the impact of the construction activity is to substitute ordinary Portland cement by pozzolanic materials. The application of using agricultural waste in the production of pozzolanic material is technically feasible, due to the calcination of organic materials and leaving ashes with a fine particle size and high SiO2 content. In the present, it is discussed the pozzolanic effect of sugarcane bagasse ash (SCBA) from Taretan, Michoacán, Mexico, on the physical and mechanical properties of a portland cement mortar. Test specimens were prepared based on replacing sugarcane bagasse ash percentages of 5, 10, 15, 20 and 30 %, relative to the weight of cement. To validate the mechanical properties of the specimens, tensile, flexural and compressive strength was determine. The porosity of the mortar was determined by means of non-destructive ultrasonic testing of pulse rate and electrical resistivity. The contribution of this paper was determine the bond strength of an overlay mortar with SCBA bonded to the concrete substrate by pull-out tests. The results showed that the addition of the sugarcane bagasse ash improved the mechanical strength, adherence of the mortar to concrete, and decreases the porosity on large curing times. Hence, it is suggested the use of Portland pozzolan cement containing sugarcane bagasse ash pozzolan, with the added benefit on the use of agricultural waste.


2012 ◽  
Vol 238 ◽  
pp. 57-60 ◽  
Author(s):  
Shu Ling Gao ◽  
Wei Shao ◽  
Jin Li Qiao ◽  
Ling Wang

ECC (Engineered Cementitious Composites) has ultra-high toughness and can be used in the zone needing the ultra-high tensile strain and very high durability. In order to investigate the toughness of ECC, the normal fracture energy GFis calculated and compared with ordinary concrete. The influence of the matrix (fly ash, silicon fume), the fiber (glass fiber, steel fiber and PVA fiber) and the fiber volume ratio on the GFof ECC are analyzed. The research indicates that silicon fume and glass fiber, steel fiber are all not able to be used in ECC. But flash ash and PVA fiber are very suit for using in ECC, the toughness of ECC increases with the increase of their content.


2019 ◽  
Vol 5 (1) ◽  
pp. 29 ◽  
Author(s):  
Nurullah Soylu ◽  
Ahmet Ferhat Bingöl

SIFCON (Slurry Infiltrated Fiber Reinforced Concrete) is a composite which occur hardening of the matrix phase, consists of cement, water, mineral additives, fine sand, water reducing plasticizer, and reinforced with high volume fiber (5–20%). The main difference from the high strength concrete (HSC) is the ductile behaviour at failure. However, the brittleness increases with the strength increase in HSC, SIFCON has a ductile behaviour because of the high volume fiber content, low permeability, high durability. Despite fiber content is 2-3% in fiber reinforced concrete, fiber content may be ten times more in SIFCON and ductility is gained. This concrete is suggested to be used in military buildings against explosion, industrial grounds, airports, and bridge feet. In this study, in order to investigate the compressive and flexural strengths of SIFCON, the aspect ratio and fiber volume of steel fibers were chosen as variable and the effects of these parameters on compressive and flexural strengths were investigated. In the study, steel fibers with aspect ratio of 40, 55, 65, and 80 were used in 0, 4, 8 and 12% ratios. The water/binder ratio was kept constant at 0.35. Silica fume is used 10% and water-reducing plasticizer is used 1.5% of cement by weight. 7 and 28 days cured samples were subjected to compressive and flexural tests and the results were compared. As a result of the tests carried out, increases in both the compressive and flexural strengths of SIFCON specimens were determined with increasing fiber volume up to 8%. Strength reductions were observed at higher ratios. In cases where the fiber volume is too high, it has been seen that the strengths were decreased. The reason of strength reduction can be explained by the difficulty of passing ability of mortar between the fibers. The highest strengths were obtained from fibers with the aspect ratio of 80. Increase in the aspect ratio as well as increases in compressive and flexural strengths have been found.


2011 ◽  
Vol 332-334 ◽  
pp. 735-738 ◽  
Author(s):  
Li Yan Liu ◽  
Yong Liang Han ◽  
Fei Zhang

This paper is aiming to research the impact behavior of flax fiber reinforced PP laminates considering the end use of the products. Flax yarn and Polypropylene (PP) filaments were twisted together with three fiber volume fraction 0.45, 0.50 and 0.60 to form the commingled yarns which were woven into fabrics as prepreg with plain and twill structures respectively. The prepregs of different layers were pressed into flax reinforced PP composites in the process of hot-pressing. The laminates with different fiber volume fraction, layer, and woven structure were tested and analyzed respectively aiming at the impact resistibility in succession. SEM micrograph of the impact fracutured surface was observed and analyzed as well. The results reveal that the impact properties of laminates with twill structures are prior to those of laminates with plain structures when other technical parameters are the same. The ability of impact resistibility of flax reinforced PP laminates improves with the increase of the fibre volume fraction, layer amount and impact velocity respectively in this research.


Author(s):  
Ali A. Shubbar ◽  
Monower Sadique ◽  
Mohammed S. Nasr ◽  
Zainab S. Al-Khafaji ◽  
Khalid S. Hashim

Author(s):  
Manish Ram E ◽  
Sindhu Vaardhini U

Utilization of the waste products in the agricultural industry has been the focus of Research for economic, environmental, and technical reasons. Sugarcane Bagasse Ash (SCBA) is one of the promising material, with its potential proved to be used as a partial replacement of cement as well as mineral admixtures for producing concrete; properties of such concrete depend on the chemical composition, fineness, specific surface area of SCBA. An experimental investigation will be carried out to examine the impact of replacing cement by bagasse ash to the mechanical and physical properties of pastes and mortars, fresh and harden concrete such as consistency, setting time and workability, compressive strength. Sugarcane Bagasse Ash powder used by replacing fly ash at 40%, 50%, and 60%. Compressive strength and water absorption test will be carried out for evaluating the performance of the material.


Materials ◽  
2019 ◽  
Vol 12 (17) ◽  
pp. 2666
Author(s):  
Li ◽  
Liu ◽  
Wu ◽  
Wu ◽  
Wu

An engineered cementitious composite (ECC) was reinforced with a steel grid and fibers to improve its tensile strength and ductility. A series of tensile tests have been carried out to investigate the quasi-static tensile capacity of the reinforced ECC. The quasi-static tensile capacities of reinforced ECCs with different numbers of steel-grid layers, types of fibers (Polyvinyl alcohol (PVA) fiber, KEVLAR fiber, and polyethylene (PE) fiber), and volume fractions of fibers have been tested and compared. It is indicated by the test results that: (1) On the whole, the steel grid-PVA fiber and steel grid-KEVLAR fiber reinforced ECCs have high tensile strength and considerable energy dissipation performance, while the steel grid-PE fiber reinforced ECC exhibits excellent ductility. (2) The ultimate tensile strength of the reinforced ECC can be improved by the addition of steel grids. The maximal peak tensile stress increase is about 50–95% or 140–190% by adding one layer or two layers of steel grid, respectively. (3) The ultimate tensile strength of the reinforced ECC can be enhanced with the increase of fiber volume fraction. For a certain kind of fiber, a volume fraction between 1.5% and 2% grants the reinforced ECC the best tensile strength. Near the ultimate loading point, the reinforced ECC exhibits strain hardening behavior, and its peak tensile stress increases considerably. The energy dissipation performance of the reinforced ECC can also be remarkably enhanced by such an increase in fiber volume fraction. (4) The ductility of the steel grid-PVA fiber reinforced ECC can be improved by the addition of steel grids and the increase of fiber volume fraction. The ductility of the steel grid-KEVLAR fiber reinforced ECC can be improved by the addition of steel grids alone. The ductility and energy dissipation performance of the steel grid-PE fiber reinforced ECC can be improved with the increase of fiber volume fraction alone. A mechanical model for the quasi-static initial and ultimate tensile strength of the steel grid-fiber reinforced ECC is proposed. The model is validated by the test data from the quasi-static tension experiments on the steel grid-PE fiber reinforced ECC.


Sign in / Sign up

Export Citation Format

Share Document