3. Book Chapters
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Item A Study on the Seismic Behaviour of Embankments with Pile Supports and Basal Geogrid(2020) Patel R.M.; Jayalekshmi B.R.; Shivashankar R.For constructing the roads on soft grounds, basal geogrid-reinforced pile-supported embankments are a suitable solution over other conventional ground improvement techniques like preloading, embankment slope flattening, removing and replacing the soft soil, etc. Many studies are available on these basal geogrid-reinforced piled embankments to understand their behaviour under static loading conditions. But it is necessary to understand the behaviour of these geogrid-reinforced piled embankments under seismic excitations. Hence, finite element analysis of three-dimensional models of embankment having crest width of 20 m, height above ground of 6 m, with side slopes of 1V:1.5H consisting of pulverized fuel ash, overlying soft marine clay of 28 m thickness is carried out under seismic excitations corresponding to Zone III (IS:1893). Soft marine clay layer is improved by the addition of piles arranged in square grid pattern with 5.75% area replacement ratio. Geogrid with a tensile modulus of 4600 kN/m is used as the basal reinforcement. Initially, the embankment is analyzed without geogrid reinforcement and pile supports. Then, it is analyzed with (i) Basal geogrid (ii) With pile supports (iii) With basal geogrid and pile supports. The influence of various parameters of the embankment on maximum crest displacements, differential settlements at crest, toe horizontal displacements, stresses at pile head and foundation soil between piles and pile bending moment along the depth at peak acceleration are studied. Analysis of results shows that the embankment supported over piles with basal geogrid reinforcement will experience less crest settlements, differential settlements at crest and toe horizontal displacements due to earthquake load. © 2020, Springer Nature Singapore Pte Ltd.Item Additive Manufacturing of Lattice Structures for Heat Transfer Enhancement in Pipe Flow(2021) Koneri R.; Mulye S.; Ananthakrishna K.; Hota R.; Khatei B.; Bontha S.Additive manufacturing has added a new dimension to manufacturing technology. The Design for Additive Manufacturing (DFAM) principles provide guidelines for successful 3D printing. Several industrial applications utilize the cellular structures in AM for design improvement by light weighting, topology optimization, etc. Self-supporting behavior is the most desired characteristic for DFAM of cellular structures. In the present work, gyroid, star kagome and BCC cellular structures are evaluated for self-supporting behavior using Materialize Magics software. The lattice designs of different sizes are 3D printed and visually examined for defects. The lattice designs are introduced into a smooth circular pipe. Conjugate heat transfer analysis is done for different Reynolds numbers (1193–10736) using FloEFD to study heat transfer and pressure drop characteristics. All the lattice designs show heat transfer enhancement and higher pressure drop with respect to smooth pipe. Among all lattice designs, gyroid shows the highest heat transfer enhancement and highest pressure drop. © 2021, The Editor(s) (if applicable) and The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd.Item Wireless monitoring and control of deep mining environment using thingspeak and XBEE(2020) Ramesh B.; Panduranga Vittal K.The possibility of remotely monitoring and controlling the deep mining environment using Raspberry Pi is studied in this paper. The use of sensor and thingspeak to get the sensor data in the web and to obtain its graph in real-time is explored. Then the controlling of the raspberry pi with the help of XBee communication and remotely controlling by computer is studied. This is done for the moisture level control by using relay and pump as an example. This can be extended to other type of sensors which are of relevance in the deep mining environment and for internet of things applications. © Springer Nature Switzerland AG 2020.Item Characterization of Mechanical and Microstructural Properties of FA and GGBS-Based Geopolymer Mortar Cured in Ambient Condition(2021) Prasanna K.M.; Tamboli S.; Das B.B.Fly ash-based geopolymer mortars require heat curing to achieve its properties, which limits its practical application at ambient conditions. The present study was aimed to accomplish the need for application of fly ash-based geopolymers for practical viability without any heat curing by inclusion of ground-granulated blast furnace slag (GGBS). The results revealed that inclusion of GGBS as a partial replacement to fly ash (FA) in geopolymer mortar, which is cured in ambient curing condition, can be able to achieve required setting time and compressive strength. Amalgamation of GGBS with class FA as binder in geopolymerization lend a hand to attain compressive strength as well as setting time which is analogous to ordinary Portland cement (OPC). Microstructural properties were studied using scanning electron microscopy. © 2021, Springer Nature Singapore Pte Ltd.Item Void-aware routing protocols for underwater communication networks: A survey(2021) Nazareth P.; Chandavarkar B.R.Underwater Acoustic Sensor Networks (UASNs) is a technology used in several marine applications like environment prediction, defense applications, and discovering mineral resources. UASNs has several challenges like high bit error rate, high latency, low bandwidth, and void-node problem during routing. In the context of routing protocols for underwater communication networks, the void-node problem is one of the major challenging issues. The void-node problem arises in the underwater communication during the greedy-forwarding technique, due to which packet will not be forwarded further toward the sink. In this review paper, we analyze the void-node problem in underwater networks and issues related to the void-node. Also, we elaborate on the significant classification of void-handling routing protocols. We analyze both location-based and pressure-based void-handling routing protocols. © Springer Nature Singapore Pte Ltd 2021.Item Application of Andreassen and Modified Andreassen Model on Cementitious Mixture Design: A Review(2021) Snehal K.; Das B.B.Cement is a widely used construction material and its consumption on large-scale causes environmental degradation; thus, more emphasis is being given on industrial by-products as alternative materials to cement for their sustainable usage. It is necessary that varying particle size of supplementary cementitious particles is to be used for filling the voids to form a dense particle-packed concrete. The selection of right combination of material is tedious job by trials involving different replacement materials and the resultant concrete may show unexpected results; thus, a more suitable method is the selection of materials based on optimum packing of particles. To select the optimum size of replacement materials particle packing models are essential, so that a low-cement concrete can be prepared which will be ecological as well as economical with improved density, low porosity and high compressive strength. It is found that there are different models have been developed to achieve optimal packing. However, application of Andreassen and modified Andreassen models for the particle packing of multiple ingredients of cementitious matrix found to be largely being accepted by the researchers. This paper reviews the application of Andreassen and modified Andreassen models for the effective particle packing investigations on cementitious particles. It also reviews the software’s employed for designing various cementitious mixtures based on Andreassen and modified Andreassen models. © 2021, Springer Nature Singapore Pte Ltd.Item A Review on Mechanical and Microstructure Properties of Reinforced Concrete Exposed to High Temperatures(2021) Goudar S.K.; Gedela S.K.; Das B.B.This paper presents the recent research progress on the response of concrete exposed to fire or high temperatures. The main highlight of this review paper is a compilation of previously reported data regarding the variations in mechanical properties and microstructure properties of concrete when exposed to high temperatures. The concrete structures get deteriorated at the macro- and microscopic levels due to high-temperature exposure. The macro-level damages can be measured with degradation in mechanical properties such as the reduction in compressive strength, weight loss, changes in elastic properties, reduction of bond strength in reinforced concrete, etc. The macro-cracks on the surface of concrete causes spalling which can be observed after exposing the concrete samples to more than 300 ℃. The compressive strength of the concrete reduces slightly till 400 ℃, and when the temperature increased to 600 ℃, there was an exponential reduction in the compressive strength of concrete. Another important parameter is bond strength degradation, which plays a crucial role in durability issues. To understand the deterioration phenomenon and changes in mechanical properties, the changes at the level of the microstructure of concrete need to be understood. Dehydration of products causes deterioration of mechanical properties and weight loss of concrete when exposed to high temperatures. At different temperatures, the microstructure changes and the response of hydration products such as calcium hydroxide (CH), CSH gel, unhydrated cement and capillary water reported by previous researchers are compiled and discussed. © 2021, Springer Nature Singapore Pte Ltd.Item Techniques to improve gain-bandwidth 5g ics(2021) Vignesh R.; Kumar R.; Song H.; Kumar S.This chapter introduces a basics of designs and techniques to improve gain-bandwidth for 5G ICs. The major focus would be on the various network topologies that yield to provide easy implementation of on-chip components for 5G-ICs. Section 1 discusses the basics of RLC tank networks, which includes RC parallel network, RLC network and series to parallel resonant network. The parameters such as quality factor, noise of filter networks are shortly refresh while foundation of resonant circuits would set-up for 5G transceiver ICs. Section 2 introduces coupled resonator networks can be used as microwave components to achieve a better gain-bandwidth trade-off. Finally, Sect. 3 will provide transformer resonators and circuit to reduce bulky components and enhance gain-bandwidth of ICs. © Springer Nature Singapore Pte Ltd. 2021.Item Ontological Structure-Based Retrieval System for Tamil(2021) Rajendran S.; Soman K.P.; Anandkumar M.; Sankaralingam C.Ontological structure of Tamil (OST) is an outcome of an extensive research activity that went on in the field of lexical semantics of Tamil for the last three decades. Rajendran’s (Semantic structure of Tamil vocabulary. Report of the UGC sponsored postdoctoral work (in manuscript). Deccan College Post-Doctoral Research Institute, Pune, 1983) post-doctoral research work went through several stages before culminating into OST. It depicts the travel from Tamil thesaurus to Tamil WordNet and into OST. OST is a lexical resource which amalgamates all sorts of information available in a dictionary, thesaurus and WordNet. The Dravidian WordNets (in which Tamil WordNet is one of the four components) built under the Indo-WordNet project depended on an ontology developed by Western conceptualization of the world found in English. This has not taken into consideration the Indian conceptualization of the world depicted in the nikhandu tradition. There are many lexical gaps between English WordNet and Tamil WordNet. Moreover, building a WordNet based on Hindi WordNet which in turn is built on English WordNet will take many years to complete and it would miss the conceptualization depicted in Indian tradition. Apart from this, the extension approach of building Tamil WordNet using Hindi WordNet cannot fulfil Dravidian conceptualization. A merger approach of building separate WordNets and collapsing them into one would have been a preferable approach. The present OST tried to overcome the lacunae found in Tamil WordNet. OST is based on the Indian and Dravidian conceptualization and the process of building one is comparatively very simple. We have the plan to mend it into a generic one so that all the Dravidian languages can be easily accommodated into it. © 2021, Springer Nature Switzerland AG.Item Strength Behavior of Rammed Earth Stabilized with Metakaolin(2020) Thiviya S.K.; Krishnan A.G.; Kalathuru M.; Sharma A.K.; Kolathayar S.Rammed earth is an ancient construction technique practiced in India and in other parts of the world. The ancient traditional technique was of the un-stabilized method but incorporating suitable stabilizing materials will improve the strength of rammed earth construction. The main objective of the present study is to assess the behavior of the rammed earth with metakaolin. The suitability of the soil was tested based on sieve analysis and followed by mini compaction tests; optimum moisture content for the rammed earth construction for the selected soil was fixed for different proportions of binders with the soil. From the compaction results, the binder content was fixed for stabilization of rammed earth. The unconfined compressive strength of the sample was found for the samples at 7, 14, 28 days of curing, and microstructural studies of the samples were performed. The compression strength of rammed earth cubes was tested and also the durability of the cubes was determined by the spray erosion test. © 2020, Springer Nature Singapore Pte Ltd.