Vellore Institute of Technology (VIT) is a private university located in&nbsp;Tamil Nadu, India. Founded in 1984, as Vellore Engineering College, the institution offers 20 undergraduate, 34 postgraduate, four integrated and four research programs. It has campuses in Vellore, Amravati, Bhopal and Chennai.

VIT is one of the top ranked private universities in India according to NIRF, THE and QS Rankings.&nbsp;Govt. of India has recognized&nbsp;VIT, Vellore as an&nbsp;Institution of Eminence. This has allowed VIT to take independent quality initiatives and move up in world ranking.

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VIT University

Many materials have been tried and tested as partial replacement of cement in concrete, either waste by-product of any manufacturing process or abundant mineral. Materials commonly used as partial replacement of cement are fly ash, ground granulated blast furnace slag (GGBFS), silica fume, bagasse ash, foundry ash, wollastonite, metakaolin, and so on. A significant issue with concrete is its brittleness (weak flexural strength), and this brittleness could be reduced by providing fibers into the concrete to increase its tensile capacity. Here, we will extensively discuss wollastonite and its various effects on concrete as partial replacement of cement or sand. Mines of Wollastonite is available in Rajasthan, Andhra Pradesh, Tamil Nadu, and Uttarakhand. In 2017, India was the second-largest producer of wollastonite after China. Wollastonite is used as microfibre; hence they increase the flexural strength of the concrete. It also reduces drying-shrinkage, abrasion loss, water absorption, and enhances concrete durability due to sulfate attack. It has been found that wollastonite-fly ash and wollastonite-micro silica combinations densify concrete at high replacement levels, thereby improving the mix's strength and durability characteristics. When using recycled waste ceramic aggregates (RWCA) in concrete, strength, and workability are maximum at 30% replacement of cement by wollastonite. © 2020 Elsevier Ltd

World University root node

Department of Structural and Geotechical Engineering

School of Civil Engineering

Vellore Campus

Journal of Cleaner Production

Research initiatives on the influence of wollastonite in cement-based construction material- A review

Recent researchers are giving more importance to cut the practice of ordinary Portland cement (OPC) by replacing the cementitious properties with industrial by-products in construction materials as supplementary cementitious materials (SCM). Many researchers are using Sugarcane Bagasse Ash (SCBA) as SCM which is an industrial by-product. Generally, SCM are pozzolanic materials which are rich in alumina and silicate. Naturally these pozzolanic materials may not be cementitious, but had tendency to react with calcium hydroxide and water in order to form cementitious compounds. The present paper reviews the processing adopted on sugarcane bagasse ash in order to transform it into supplementary cementitious material. The procedure to develop the sugarcane bagasse ash as a pozzolanic material is planned through a structure. The chemical compositions and physical properties of SCBA from the various sources are has been discussed. Furthermore, the influence of grinding and calcination on the characterisation of sugarcane bagasse ash has been discussed. Basically, the characterisation of sugarcane bagasse ash were studied on the basis of physical properties, chemical properties and microstructural studies. This review paper focuses on micro analytical studies of SCBA samples with respect to X-ray powder diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), Transmission electron microscopy (TEM), and Scanning electron microscope (SEM). The micro analytical investigation reveals that grinding made SCBA finer and calcination process had reduced the carbon the content in SCBA along with there is an increase in the amorphous reactivity as due to the increment in pozzolanic oxides, observed in X-ray fluorescence (XRF).

VIT Unitversity

Department of Chemical Engineering

School of Chemical Engineering

An overview of the influences of mechanical and chemical processing on sugarcane bagasse ash characterisation as a supplementary cementitious material

The aim of this study is to decolorize reactive dyeing effluent by of solar based photo-Fenton process coupled with lime flocculation, with an objective of reducing reagent requirement of Fenton process and improve the pH of the treated effluent. Coupling with lime flocculation has reduced forty percent of H2O2 reagent requirements of photo-Fenton process for 98% decolorization of simulated reactive dyeing wastewater after a reaction period of 60 minutes and improved effluent pH. It is clear from the literature survey that greater reagent dose of Fenton process is required to decolorize reactive dye effluents containing auxiliary chemicals compared to aqueous solution containing reactive dye alone, due to the inhibitive effect of excess chloride ion present in wastewater. Burnt clay bricks made from chemical sludge, produced during lime flocculation, by replacing 20% of brick earth have the same properties as a standard burnt clay brick and are acceptable from environmental point of view. © 2006-2020 Asian Research Publishing Network (ARPN). All Rights Reserved.

ARPN Journal of Engineering and Applied Sciences

Decolorization of Reactive Dyeing Effluent By Solar Photo-Fenton Process Coupled With Lime Flocculation

Many researchers are using sugarcane bagasse ash as a pozzolanic admixture. Pozzolanic admixture is an amorphous aluminosilicate materials, which may not be naturally cementitious, but react with calcium hydroxide (Ca(OH)2) ande water to form cementitious compounds. Mostly Fly ash and other pozzolanic materials have been utilized as raw materials in Geopolymer concrete. However, sugarcane bagasse ash is also rich in aluminosilicate source, which is a primary requirement for the geopolymer concrete. This experimental study was to synthesize geopolymer from sugarcane bagasse ash and metakaolin in order to effectively utilize both these low cost and easily available materials. In this study physico-chemical and morphology characterization of sugarcane bagasse ash and metakaolin were studied and observed that sugarcane bagasse ash needed mechanical as well chemical treatment in order to enhance its pozzolanic reactivity. In the chemical processing of sugarcane bagasse ash, calcination has been carried out at 700 °C for 90 min. while in mechanical treatment grinding has been done for 2 h grinding in ball mill. For synthesizing geopolymer three parameters were considered i.e. effect of silica/alumina ratio, effect of alkaline activator/binder ratio and effect of sodium silicate/sodium hydroxide ratio, while the molarity of sodium hydroxide was fixed i.e. 6 M. In silica/alumina ratio, four ratios were considered i.e. 2.0, 2.5, 3.0 and 3.5. In alkaline activator/binder ratio 0.45, 0.50, 0.55 and 0.60 ratios were taken. Lastly in sodium silicate/sodium hydroxide ratio 2.0, 2.5 and 3.0 were considered. Finally the optimal mix proportion was defined based on the 28 day compressive strength and it was observed 2.5 silica/alumina ratio was the optimum ratio among the other silica/alumina ratios. In alkaline activator/binder ratio and sodium silicate/sodium hydroxide ratio 0.50 and 2.5 ratio respectively was the optimal ratio.

Construction and Building Materials

Synthesis and characterization of geopolymer from metakaolin and sugarcane bagasse ash

This study is aimed at investigating the durability properties of Composite Fiber Reinforced High-Performance Concrete. A 15% partial replacement of cement by weight was done with ultra-fine fly ash. The addition of nanosilica was in fractions of 0%, 1.5%, 3.0% and 4.5% by weight of cement. For each of the above combinations, 1.0% steel and 0.25% polypropylene fibers, respectively, by volume of the binders were added. A constant aggregate binder ratio of 2.0 and varying water binder ratios of 0.275, 0.300, 0.325 were used in this investigation. The sorptivity test was performed to assess the rate of absorption, and the rapid chloride permeability test (RCPT) was performed to assess the permeability of concrete. Test results revealed that all the mixes attained low to very low chloride permeability. The decrease in chloride ion permeability for mixes with nanosilica and ultra-fine fly ash ranged from 53.83% to 71.45% for 28 days curing period and 55.88% to 74.27% for 56 days curing period, as against the reference mix. ‘Residual Compressive Strength’ and ‘Percentage Weight Loss’ for 28 and 56 days of immersion in 5% concentrated solutions of HCl, H2SO4, and MgSO4 were evaluated to study the effects of aggressive ions such as chlorides and sulfates on concrete. The weight loss observed ranged from 7.09% to 2.07% in the case of HCl, from 7.96% to 2.86% in the case of MgSO4, from 17.93% to 11.02% in case of H2SO4 for water binder ratio of 0.275 and 56 days of immersion. The percentage reduction in strength after 56 days of immersion for mixes with water binder ratio of 0.275 ranged from 14.39% to 8.92% in HCl, from 14.53% to 9.66% in MgSO4 and 14.81% to 10.92% in H2SO4. The outcomes of the study showed that a combination of 15% ultra-fine fly ash and 3% nanosilica is the optimum replacement level to achieve increased durability, reduced porosity and permeability due to improved macro and micrometer densities of concrete. In addition, steel and polypropylene fibers have also made a small contribution towards improving the durability of Composite Fiber Reinforced High-Performance Concrete. © 2020

Experimental study on durability characteristics of composite fiber reinforced high-performance concrete incorporating nanosilica and ultra fine fly ash

The inclination of the construction industry to use sustainable materials in producing a more benign concrete is gaining popularity. In addition to this, economic viability along with performance plays a key role in the contemporary research work on various new alternatives and substitutes. This paper deals with the partial replacement of cement with Alccofine and addition of 0.1% wt/volume water dispersed Graphene Oxide in 1:3 cement sand mortar mix. The w/c ratio was maintained at 0.30 along with water reducing agent. The study initially focused on arriving at the optimum Alccofine replacement percentage. Compressive and flexural strength of the systems with varying dosages of Alccofine replacement level at 10%, 15% and 20% showed promising improvement at 15% replacement level, when compared system CM-0AL. GO was introduced in the Alccofine optimized mix at dosage rate of 0.03%, 0.05%, 0.09%, 0.15% and 0.21%. The addition of water dispersed GO showed an improvement in both compressive and flexural properties, peaking at 0.05% followed by slow decline in the strength parameters. GO accelerates the rate of hydration along with acting as nano-scale fibres filling the micro-pores and voids, attributing to the improved results. However at higher levels, the agglomeration of GO contributes to the improper filling of voids. The workability increased considerably by the addition of Alccofine. Thus, it is inferred from the study that the partial replacement of cement with Alccofine serves a dual fold benefit being eco-friendly material, reducing the carbon footprint whilst improving the workability and mechanical strength. The addition of water dispersed GO augmented the results obtained with the optimized mix. The best results were observed for the system with 15% Alccofine replacement along with 0.05% water dispersed GO. © 2019 Elsevier Ltd.

Materials Today: Proceedings

Study on Mechanical Properties of Mortar using Alccofine and Graphene Oxide

The present study has made an emphasis for comparing the strength characteristics of ferrocement panels with panels made with HDPE geogrids. Also, an attempt has been made to replace cement partially by silica fume; which is a by-product obtained from the production of silicon and ferrosilicon alloys in the electric arc furnaces. The rise in the cost of river sand used as fine aggregate in concrete has increased the cost of construction significantly in the past few decades. Foundry Sand, which is obtained from the Foundry Industries are treated as waste materials that have the recycling capability in concrete and it is been proposed for partially replacing sand in this study. Different mix proportions using the above materials have been made and panels were prepared for optimum proportion based on the compressive and tensile strength of cube and cylinder specimens. Panels with two layers of steel mesh and geogrid mesh were cast. A comparative study on strength characteristics has been made and failure patterns of the panels have been studied. It was shown that strength of geogrid panels was on par with ferrocement panels and are advantageous to ferrocement panels in corrosion resistance and elasticity

Effect of Silica Fume and Foundry waste sand on strength characteristics of Geogrid and Ferro cement panel

In this work, the reinforcing effects of Graphene Oxide Nanosheets dispersions (GOD) on high strength cement mortar are investigated, evaluating possible improvements in mechanical properties, fluidity, Sorptivity and water absorption resistance. Mortar with water/cement ratio of 0.5, GOD dosage varying from 0 to 0.20% by weight of cement and sand at a proportion of 3× weight of the cement were prepared, in addition to 10% and 20% replacement/no replacement with Silica Fume and Metakaolin respectively to improve the GO nanosheets dispersion. The GO used in the matrix forms aggregate due to presence of divalent Calcium ions. Hence to split the particles vigorous mixing was done. The results indicate that the addition of GOD accelerate the cement hydration reactions, increase the compressive strength and tensile strength of the mortar, reduce the pore volume and harden cement properties. However, the fluidity decreased with increasing GOD content. The optimal compressive strength was achieved with samples designed with GOD dosage of 0.05% with replacement, for which the corresponding increases were 72.41%, 84.61% and 90.90%, after 3,7 and 28 days respectively, compared with samples without GOD and replacement. The tensile strength of the cement mortar increased with GOD content to 132%, 178.6% and 181.2% for 3, 7 and 28 days respectively with replacement and GOD dosage of 0.10%. Furthermore, FE-SEM observation indicated that the GOD probably had an effect on the shape of the cement hydration products. It revealed samples containing 0.10 wt% GOD with replacement exhibited good bonding between the GOD and the surrounding cement matrix. The hydration mechanism of cement composites with GOD and replacement of cement with Silica Fume and Metakaolin needs further study. © 2018 Elsevier Ltd

Effect of Graphene Oxide Nanosheets dispersion in cement mortar composites incorporating Metakaolin and Silica Fume

This paper presents the static lateral load behaviour of single pile in comparison with 3x3 pile group in sand. The piled raft system is modelled using PLAXIS3D. Parametric studies of varying length to diameter (L/D) and spacing of piles in a group and diameter of piles (S/D) have been performed. The behaviour of group piles in terms of static lateral load capacity and group efficiency has been discussed. © Published under licence by IOP Publishing Ltd.

Fulltext

IOP Conference Series: Materials Science and Engineering

Static behaviour of 3x3 pile group in sand under lateral loading

Pharmaceutical sector plays an important role in the medical and health system. Due to the globalization of the business, increasing demand and supply for drugs, growing regulatory requirements, all stages of the pharmaceutical supply chain (SC) are facing numerous predicaments. The traditional way of selection and evaluation of these predicaments is customarily done using technical information. This approach lacks the ability to project the burning issue that to be addressed first. Hence, a computing method of selecting the crucial issue from the existing issues is essential in a pharmaceutical supply chain. This paper considers seven different predicaments as criteria and five sub-criteria under each main predicament of a pharmaceutical supply chain. The intention of this project is to manifest the process of assessing and selecting the issue that to be addressed first by using multi-criteria decision making technique (MCDM), i.e., fuzzy analytical hierarchy process (FAHP). The criteria and sub-criteria weights are calculated and priority assessment of the predicaments is done by using FAHP. Finally, from the findings of this work, the predicaments are ranked from most important to least important. This gives information to the decision maker (DM) to solve the issue that is affecting the SC the most with respect to the others. © Published under licence by IOP Publishing Ltd.

Department of Manufacturing Engineering

School of Mechanical Engineering

Evaluation and Selection of Predicaments in Pharmaceutical Supply Chain using AHP under Fuzzy Environment

The major concern in flat slabs is the concentration of high stresses in the slab column connection resulting in punching shear failure of the entire slab system. Hence in the present study an attempt has been made to study and analyze the effect of edge column in a flat slab. A numerical investigation was conducted using the finite element software ABAQUS to evaluate their ability to resist punching shear in a flat slab. The nonlinear characteristics of concrete were achieved by employing the concrete damaged plasticity model in the finite element program. Linear and nonlinear analysis of edge slab-column connection was carried out for slab of depth 150mm and 200 mm. Remarkable reductions in deflection is observed when the depth of slab is increased. © IAEME Publication.

International Journal of Civil Engineering and Technology

Study on edge slab-column connection in flat slab

The network functionaries incorporate and core networks aim to provide 99.999% reliability to their networks. The most preferred way to achieve this is to provide dynamic routing to the network. If the router gateway is disrupted by port failure, network administrator should manually configure the route in which packets are being forwarded. By using Hot Stand Routing Protocol (HSRP), it simultaneously adapts new route, which provides redundancy to the network with reduced packet loss. In this paper, our aim is to calculate the difference in number of packets lost when router with gateway is disrupted in the network by combining HSRP with Open Shortest Path First (OSPF) protocol. By using this combined technique, we can reduce the packet loss to maximum extent thereby increasing the reliability. The simulation results provide best route when HSRP is combined with OSPF than the existing technique without HSRP.

Department of Communication Engineering

School of Electronics Engineering

Indian Journal of Science and Technology

Performance Analysis of HSRP in Provisioning Layer-3 Gateway Redundancy for Corporate Networks

In this study the effect of nano-silica on cement-silica fume paste, mortar and concrete is studied at three different water-binder ratios: 0.20, 0.25 and 0.30. By adopting a systematic procedure most suitable nanosilica was selected from a set of commercially available nano-silicas. Most effective superplasticiser was selected from a set of super plasticisers and used in the paste, mortar and concrete to achieve maximum dispersion of the particles in the cementitious system so as to attain maximum flow. The compressive strength of these systems was tested at curing ages of 3,7,14, 28 and 56 days. The microstructure of the same system was also studied using the various instruments such as X-ray Diffraction (XRD), Scanning Electron Microscope (SEM) and Atomic Force Microscope (AFM). The results obtained from the specimens were compared with controlled specimens. As expected, the results showed that nano-silica increased the compressive strength as well improved the microstructure due to pozzolanic as well as filler action. Copyright © 2013 ACC Limited.

Indian Concrete Journal

Effect of nano-silica on strength and microstructure of cement silica fume paste, mortar and concrete

Using pond ash in place of sand, this study assesses concrete's compressive strength and resistance against acid, chloride and sulphate attacks. The pond ash replacement levels were 10%, 20%, 30%, 40% and 50%. The compressive strength of different grades of concrete was tested at 7, 28, 56 and 90 days using cubical specimens. The resistance of concrete against chemical solutions such as hydrochloric acid, magnesium sulphate and sodium chloride was evaluated at 28 and 56 days. The results obtained from the specimens with pond ash were compared with a specimen without pond ash. As expected, the concrete's compressive strength increased with age and its performance against adverse environmental conditions was satisfactory.