Papers by Dr. Ashwin M Joshi
Social Science Research Network, 2015
Masonry Mortar is basically a binding agent that is composed of acementitious material, fine aggr... more Masonry Mortar is basically a binding agent that is composed of acementitious material, fine aggregates and water. The main purpose of the mortar is to sewmasonry units (blocks/bricks) into thesingle integral unit. Conventionally used mortar is cement sand mortar in the proportion 1:6 (Cement: River Sand). Over the past few decades,man has exploited the natural resources at a severe rate.Good quality Natural River Sand stands first in the list of construction materials that are on the verge of extinction due to excessive and unnecessary consumption in theconstruction process. One has to adapt to alternative materials that can be used as an effective replacement over 'Natural River Sand' in Masonry Mortar without affecting its efficiency. This paper focuses on the experimental analysis of six such alternatives that have the potential to replace Natural River Sand in amortar.Mortars prepared from these alternativessatisfies the minimum strength requirement as per IS code. Thus, the use of such alternativesto natural sand for mortars in masonry construction would deliver an efficienteconomical and sustainable structure.
Social Science Research Network, 2021
Developing concrete using alternatives to natural resources is an important issue for environment... more Developing concrete using alternatives to natural resources is an important issue for environmental protection along with preserving the natural resources and saving of energy for sustainable development. Metal foundries use large amount of sand as part of the metal casting process. Foundries successfully recycle and reuse the sand many times in the casting process. When the sand can no longer be reused in the foundry, it is removed from the foundry it is termed as "waster foundry sand". The constant depletion of sand beds at all major sources of availability is major concern and thus effects are taken in order to either abolish or replace sand in construction activities particularly in concrete. In present experimental investigation is carried out to evaluate the properties of fresh and hardened concrete containing waste foundry sand as fine aggregate partial replacement. The percentages of replacement 0%, 15%, 20%, and 25% by weight of fine aggregate and tests like slump test, compression strength test, split tensile strength test, flexural strength test and sulphate attack test were performed for all replacement levels of foundry sand for M40 grade concrete. From the test result, the waste foundry sand can be replaced partially up to 20% of fine aggregate in concrete, will be both economical and for high strength purpose.
Social Science Research Network, 2017
Construction plays a very important role in economic growth through the multiple effects on the o... more Construction plays a very important role in economic growth through the multiple effects on the other sectors of the country’s economy. Precast construction concept includes those structures where the majority of structural components are standardized and produced in plants or yards in a location nearer or away from the construction site, and transported to the site location for its assembly. The standardized precast elements facilitate mass production, in order to build a large number of buildings in a short duration. In the present case study, where the project consists of 62 towers with twelve floors each. The precast construction method has been adopted as the moulds of standardized components facilitates mass production with stringent quality control. Precast construction method involves setting up of casting yard, production & stacking, transportation and erection of precast elements. Precast Construction is effective in terms of time, labours requirement, superior quality, better performance & finish, optimal material requirement, less wastage, reduced use of shuttering, desired shape, better finish etc., It is convenient to establish precast yard and to erect the precast elements at (near) site which speeds up the process & contributes towards mitigating delays in large scale construction projects. As this method requires huge initial investments, it is feasible for Large Scale Construction Projects only.
Social Science Research Network, Apr 4, 2019
Construction industry facing many challenges with respect to difficulties associated with time an... more Construction industry facing many challenges with respect to difficulties associated with time and productivity. Productivity is mainly dependent on labour effort and performance. The main objective of this study was to measure productivity and identifying the factors affecting labour productivity. The present study was carried out in the precast construction project. The first phase of the study comprises of the labour productivity measurements; productivity measurement was performed by practical observation of the finishing trades. The second phase of the study comprises of the questionnaire survey to identify the factors affecting labour productivity in building construction; Total 30 questionnaires were distributed to the project personals involves client's, contractors and consultants of different construction companies. The relative importance index technique was used to rank the questionnaire response. The results of this study recommended that construction companies have to conduct labour productivity measurements in their projects to improve labour productivity. It is important to adopt the motivational system, safety programs, schedule for procurement of materials, frequent meeting with project professionals and use project scheduling techniques etc. are discussed to enhance the labour productivity in construction projects.
Materials Today: Proceedings, 2021
Huge amount of E waste creates serious problem in all over the country. Recycle percentage of E w... more Huge amount of E waste creates serious problem in all over the country. Recycle percentage of E waste is only 12.5. Due to limited natural resources, from printed circuit boards E-waste similar non-metal parts can be recuperated and mixed as an concrete constituent. So in various experiments E waste were used as replacement of fine and course aggregate. Utilizing E waste as ingredient of concrete reduces the use of natural ingredients as well as reduces the land fill using E waste and provide smart impact on environmental problems. Generation of the E-waste and use of concrete is rapidly increasing to meet the technological advancement and demand. Intension of this study is to inspect the performance of concrete by substituting manufactured sand by E-waste. In this research work, manufactured fine aggregate (MÀsand) was partly replaced by E waste (E-sand) in different percentages (0%, 10%, 20%, 30% and 40%), with 0.45 water cement (W.C) ratio. With reference of Indian standard (IS) 10262:2019 guidelines, M30 grade concrete were prepared. The flexural, compressive, split tensile strength and chloride permeability tests were performed on concrete with various mix proportions and test results were correlate with results of reference concrete. The study reveals that, partly replacing of 20% factory-made sand (M-sand) by E waste (E-sand) yields maximum strength, better chloride permeability with improved micro structure than conventional concrete.
IOP conference series, Jul 1, 2021
The gradation characteristics of soil play an important role in the strength and durability chara... more The gradation characteristics of soil play an important role in the strength and durability characteristics of soil-based construction material like soil-cement blocks, adobe, rammed earth, mud concrete, and so on. In addition, the water content at which these stabilized soil-cement composites are moulded along with the quantity of stabilizer content also influence their characteristics. The water content at which the adobe is pugged and moulded is also important. The current study attempts to understand the influence of soil gradation, especially the variation of silt and clay content, at a constant stabilizer content on the pugging moisture of the fresh stabilized adobe mixes. The experimental program also attempts to understand and establish the relation between optimum moisture content and optimum pugging moisture, the fresh moulded density etc for stabilized adobe mixes.
Springer eBooks, Sep 3, 2021
Journal of Remote Sensing & GIS, Jan 2, 2018
Bengaluru drainage characteristics of natural catchments have drastically altered due to unplanne... more Bengaluru drainage characteristics of natural catchments have drastically altered due to unplanned urbanization, increasing volume and rate of surface runoff. The frequent blockage of drainage system due to indiscriminate disposal of solid waste, encroachment of wetlands and increasing volume of flow makes coping up and worsening the present drainage systems. These problems of urban floods can be prevented by taking necessary precautions in places where these urban floods could occur. Remote sensing and geographical information system plays a major role in recognizing the flood prone area. Using Arc-GIS software and Google Earth images, critical bed characteristics are identified. In order to analyse physico-chemical characteristics of ground water along the banks of the river, eight water samples were collected and tested. A temporal analysis on surface water of Vrishabhavathi reservoir was made. The geo-spatial location of varying ground water quality and flood prone areas was identified by weighted overlay analysis through GIS application. Bad river bed characteristics, poor ground water quality, flood prone areas and variation in surface water quality were identified in the study. This work is concluded by suggesting corrective measures that can be carried out in these identified locations to avoid urban floods. Keywords: GIS, river bed characteristics, physico-chemical characteristics, ground water quality, river training, geo-spatial location, flood prone areas Cite this Article Gajalakshmi K, Joshi Ashwin M, Sneha AR. Prioritization, Characterization and Geo-spatial Location of River Training Structures for Vrishabhavathi River using GIS Techniques. Journal of Remote Sensing & GIS . 2017; 8(3): 33–45p.
INTERNATIONAL CONFERENCE ON SMART TECHNOLOGIES AND APPLICATIONS (ICSTA 2022)
Building pathology and rehabilitation, 2020
There is a shortage of sand for construction worldwide and the need of the hour is to find altern... more There is a shortage of sand for construction worldwide and the need of the hour is to find alternatives to river sand for sustainable and cost-effective construction. Soils, which generally have 40–50% sand content are an obvious choice. However, it should be noted that the top soil, which is essential for agriculture, should not be used. The other possible alternatives are waste products like LD Slag and Construction and Demolition waste (CDW). Since concrete is the most used construction material universally, it is beneficial to consider concretes with alternative fine aggregates. This chapter examines the use of excavated natural soil and its combinations with natural sand, LD Slag and construction and demolition waste as fine aggregates in concrete. Such concrete may be referred to as Stabilized Mud Concrete since soil is invariably one of the primary ingredients. Four different sets of fine aggregate replacements are considered. The mix proportions have been varied and the compressive strength and water absorption of various concretes are determined and reported. This approach is useful in situations where expected strength requirements lie in the range of 5.0–15.0 MPa.
i-manager’s Journal on Civil Engineering
To provide better understanding of the behavior of the fresh concrete and to enhance the quality ... more To provide better understanding of the behavior of the fresh concrete and to enhance the quality of concrete, the Self-compacting concrete (SCC) is characterized by its rheological properties, by a more scientific approach to overcome the limitations of the existing empirical test methods. In this study, SCC mixes (Powder and Viscosity Modifying Admixture type) were developed by using Portland Pozzalana Cement (PPC), ground granulated blast slag (GGBS) as a filler material, M-sand as a fine aggregate, natural angular crushed granite as coarse aggregate and with superplasticizer (SP) and Viscosity Modifying Admixture (VMA). About 12 different SCC mixes with more than 100 trials, were developed 3 3 with varying cement contents (300, 375 and 450 kg/m) and water contents (185 and 205 /m) along with varying filler contents. The experimental results show that direct shear box can be effectively used to determine the Bingham
Materials Processing & Manufacturing eJournal, 2019
Flow characterization and controlling fresh property of SCC is most critical. Even slight variati... more Flow characterization and controlling fresh property of SCC is most critical. Even slight variations in ingredients can have an adverse effect on fresh properties; strength and durability of hardened concrete. The material science approach to study rheological properties is essential in order to overcome the paucity posed while characterizing mixes by empirical methods such as the slump flow test.<br><br>In the present work, the Bingham parameters of SCC were assessed by using the direct shear box. The SCC mixes were designed with a constant volume of paste 0.38 (powder type SCC) based on absolute volume concept. The two water contents of 185 and 205 lt/cum and cement contents of 300,375 and 450 kg/cum along with slag as filler was used. A unique test procedure was followed, by applying low normal stresses of 0.025, 0.050 and 0.10 MPa with three different displacement rates of 0.25, 0.625 and 1.25mm/min under static condition. The results indicate that the direct shear b...
International journal of scientific research, 2021
Journal of Remote Sensing & GIS, 2018
Bengaluru drainage characteristics of natural catchments have drastically altered due to unplanne... more Bengaluru drainage characteristics of natural catchments have drastically altered due to unplanned urbanization, increasing volume and rate of surface runoff. The frequent blockage of drainage system due to indiscriminate disposal of solid waste, encroachment of wetlands and increasing volume of flow makes coping up and worsening the present drainage systems. These problems of urban floods can be prevented by taking necessary precautions in places where these urban floods could occur. Remote sensing and geographical information system plays a major role in recognizing the flood prone area. Using Arc-GIS software and Google Earth images, critical bed characteristics are identified. In order to analyse physico-chemical characteristics of ground water along the banks of the river, eight water samples were collected and tested. A temporal analysis on surface water of Vrishabhavathi reservoir was made. The geo-spatial location of varying ground water quality and flood prone areas was ide...
SSRN Electronic Journal, 2017
Construction plays a very important role in economic growth through the multiple effects on the o... more Construction plays a very important role in economic growth through the multiple effects on the other sectors of the country’s economy. Precast construction concept includes those structures where the majority of structural components are standardized and produced in plants or yards in a location nearer or away from the construction site, and transported to the site location for its assembly. The standardized precast elements facilitate mass production, in order to build a large number of buildings in a short duration. In the present case study, where the project consists of 62 towers with twelve floors each. The precast construction method has been adopted as the moulds of standardized components facilitates mass production with stringent quality control. Precast construction method involves setting up of casting yard, production &amp; stacking, transportation and erection of precast elements. Precast Construction is effective in terms of time, labours requirement, superior quality, better performance &amp; finish, optimal material requirement, less wastage, reduced use of shuttering, desired shape, better finish etc., It is convenient to establish precast yard and to erect the precast elements at (near) site which speeds up the process &amp; contributes towards mitigating delays in large scale construction projects. As this method requires huge initial investments, it is feasible for Large Scale Construction Projects only.
SSRN Electronic Journal, 2015
Masonry Mortar is basically a binding agent that is composed of acementitious material, fine aggr... more Masonry Mortar is basically a binding agent that is composed of acementitious material, fine aggregates and water. The main purpose of the mortar is to sewmasonry units (blocks/bricks) into thesingle integral unit. Conventionally used mortar is cement sand mortar in the proportion 1:6 (Cement: River Sand). Over the past few decades,man has exploited the natural resources at a severe rate.Good quality Natural River Sand stands first in the list of construction materials that are on the verge of extinction due to excessive and unnecessary consumption in theconstruction process. One has to adapt to alternative materials that can be used as an effective replacement over 'Natural River Sand' in Masonry Mortar without affecting its efficiency. This paper focuses on the experimental analysis of six such alternatives that have the potential to replace Natural River Sand in amortar.Mortars prepared from these alternativessatisfies the minimum strength requirement as per IS code. Thus, the use of such alternativesto natural sand for mortars in masonry construction would deliver an efficienteconomical and sustainable structure.
International Journal of Research in Engineering and Technology, 2015
Slip form paving has been extensively used worldwide for construction of pavements. During the pr... more Slip form paving has been extensively used worldwide for construction of pavements. During the process of paving, concrete mix with a slump less than 50 mm is placed in front of a paver. Because of the low consistency of the mix, a great deal of vibration is needed to move entrapped air and compact the concrete. There is a need to overcome problem by designing a concrete that would not require vibration to compact the concrete mix, at the same time stability after extrusion and high flexural strength. Mix design based on the absolute volume concept was adopted to fabricate SFSCC. Volume of paste of 0.38 and water content of 200 kg/m 3 was kept constant throughout the study. Cement content was varied from 360 to 425 kg/m 3 , 3 mixes of SCC with GGBS (SFSCC-S), 3 mixes of SCC with 2% of alccofine replaced by cement (SFSCC-SA) and 3 mixes of SCC with 2% of metakaolin replaced by cement (SFSCC-SM) is reported. The quantity of polypropylene fibers used in all the mixes was 900 gm/m 3. Slump, spread, green strength and compaction factor were evaluated for all the 9 mixes. To simulate the practical construction process, a mini paver system was fabricated. The strength parameters compressive and flexural strength of concrete was evaluated at 7 days and 28 days.
Self-compacting concrete (SCC) referred to as a type of special concrete, offers economical and t... more Self-compacting concrete (SCC) referred to as a type of special concrete, offers economical and technical advantages over the conventional vibrated concrete. So far, the design and development of SCC mixes were carried out as per Okamura Method, Nan-Su method, EFNARC, ACI, Volume fraction method and so on. For the first time, Bureau of Indian Standards has come out with guidelines for SCC mixes through IS 10262-2019 revision. The present study attempts to develop SCC mixes as per the revised IS guidelines utilizing marginal materials such as RMC sludge and granite sludge as fines (particle size less than 125 microns); recycled concrete aggregate (RCA) as coarse and fine aggregates and GGBS as a filler material. The powder content, cement content and water content were maintained at 550 kg/m3 , 334 kg/m3 and 200 lt/m3 respectively. The developed SCC mixes satisfy the requirements of fresh and hardened properties as per Indian Standard (IS) Code. The morphology of the microstructure of developed SCC mixes were also analyzed through Scanning Electron Microscopy (SEM). Results have indicated construction and demolition waste in the form of RMC sludge and granite sludge may be utilized in developing SCC mixes as per the revised IS code. SCC mixes with granite sludge has shown better performance as compared to SCC mixes with RMC sludge as fines.
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Papers by Dr. Ashwin M Joshi
sand such as granite powder, marble dust and M-Sand with commercially available ready-mix mortar
• The joint thickness for these alternative mortars were maintained around 4 – 6mm.
• Performance of thin jointed prisms v/s conventional 1:5 and 1:6 [C:FA] prisms with 15mm bed joint thickness