3. Book Chapters
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Item Performance of deep excavation for an underground metro station constructed by top-down method—A case study(2019) Muhammad Ramees Ali T.M.; Rajasekaran C.The subway system plays a vital role in reducing the traffic congestion problems in urban cities. Recently, a number of underground railway transportation networks are commissioned and opened for operation or are being constructed in many cities in India. Metro station excavations is a tough task and pose threat to public safety, due to high intricacy and uncertainty in excavation activities. The stability of deep excavation and adjacent buildings has gained highlighted concerns during metro station construction. The underground metro station under study is located in Anna Salai Road, Chennai, India. The station is located at the centre of the main street. The project comprised of three basement levels. It has a length of 240 m and a width of 19–22 m at the track level. The excavation depth is about 18.0 m. The entire site is located within a floodplain. The performance of the deep excavation and adjacent area were monitored using extensive instruments. Monitored data are analyzed and presented as a case study in this paper. © Springer Nature Singapore Pte Ltd. 2019.Item Partial replacement of steel slag aggregates in concrete as fine aggregates (induction blast furnace slag)(2019) Arjun S.; Hemalatha T.; Rajasekaran C.In this study, an attempt has been made to investigate the effect of partial replacement of conventional river sand with steel slag aggregate. The replacement of river sand by slag aggregate provides dual advantage of reducing disposal problems in steel industries and conserving the natural resources. In this study, slag aggregate originated from induction blast furnace has been used. The physical and chemical properties of slag aggregate evidenced the feasibility of using this material as a substitute for river sand. Total of three mixes made with Ordinary Portland Cement (OPC), cement replaced with fly ash and river sand replaced with slag aggregate have been considered for this study. The mix is designed for M40 grade. First mix (Control mix 0M0) made of OPC as a binder and 100% river sand, second mix (0M50) made of OPC and 50% slag aggregate and third mix (25M50) made of 25% OPC replaced by fly ash and 50% river sand replaced by slag aggregate. Mechanical and durability properties of all the three concretes are studied. It is found that the strength results of 0M0 and 0M50 are comparable indicating the suitability of using slag aggregate as an alternative for river sand. However, the third mix with fly ash replacement in binder showed reduced strength in comparison with control concrete. Hence, it is concluded that when slag aggregate is used as a partial replacement for river sand (50%), it is advisable to use OPC than the Pozzolanic Portland Cement (PPC). © Springer Nature Singapore Pte Ltd. 2019.Item Early cost estimation of highway projects in India using artificial neural network(2019) Mahalakshmi G.; Rajasekaran C.The objective of this paper is to develop a model to estimate the construction cost of a highway at early stage (conceptual phase) of a project. Cost estimation at conceptual phase is a challenge as only limited information is known. As a result, wide cost variance is eminent at the completion of project. A neural network which can aid in cost estimation is developed. Parameters that can be obtained with least effort and highly influencing on cost are chosen. Developed neural network relates overall highway construction cost described in terms of materials, duration, topography, and prevailing soil conditions. Data of 52 projects were obtained from National Highway Authority of India (NHAI). The obtained results demonstrated that a multi perceptron network with backpropagation algorithm is capable of predicting construction cost of highway with reasonable accuracy. © Springer Nature Singapore Pte Ltd. 2019.Item An experimental investigation to determine the properties of fly ash based geopolymers as per indian standards(2019) Saha S.; Rajasekaran C.Production of ordinary Portland cement requires huge quantity of natural resources and also releases huge quantity of carbon dioxide into the atmosphere. Research efforts have been continuing to establish geopolymer as an alternative cementitious material for the replacement of ordinary Portland cement. This paper presents the study to find out the properties of fly ash based geopolymer paste and 28 days compressive strength of geopolymer mortar. Standard consistency, setting time of geopolymer paste has been determined using vicat’s apparatus (according to Indian Standards), which is followed for cement paste, varying the concentration of sodium hydroxide solution from 6 to 16 M. Results indicate higher standard consistency, more time required for setting for fly ash based geopolymer than that of cement paste. Compressive strength of the geopolymer paste and mortar 17 specimens increases with the increase of the concentration of sodium hydroxide solution and decrease beyond 14 M. © 2019, Springer Nature Singapore Pte Ltd.Item Strength characteristics of laterized mortars using processed laterite(2019) Basavana Gowda S.N.; Rajasekaran C.; Yaragal S.C.The rapid pace of population growth in India has enforced the construction industry to use construction materials at an accelerated rate leads to the exhaustion of natural resources. Large-scale constructions have a severe influence on the environment instigating many threats either directly or indirectly like exhaustion of the river due to unscientific sand mining being done at a frightening level, etc. To address this issue, it is required to find substitutes for river sand for producing mortars. One among the locally available marginal resource is laterite. In this study, an attempt is made to study the performance of cement mortars using laterite as fine aggregate in replacement levels of 0, 25, 50, 75 and 100% to natural fine aggregates (river sand). Studies were carried out in two stages, initially river sand is replaced with laterite quarry waste (unprocessed laterite), and then it is replaced with the processed laterite. The flowability and compressive strength characteristics of mortars are studied. Results indicate that, the decrease in compressive strength of mortars with increase in replacement levels of river sand by unprocessed laterite was more, when compared to mortars with processed laterite. However, there is only 13% reduction in strength for laterized mortar with 100% processed laterite when compared to control mortar is observed. © Springer Nature Singapore Pte Ltd. 2019.Item Use of concrete wastes as the partial replacement of natural fine aggregates in the production of concrete(2019) Saha S.; Rajasekaran C.; Vinay K.Due to rapid development of construction industries in various dimensions, demand for construction materials is also gaining high momentum. Therefore, availability of natural sources of construction materials is going to be in decreasing trend to cope up with the high demand. Again currently, quantity of construction and demolition waste is also going too high day by day. Reuse of these construction and demolition waste is one of the promising solutions to protect natural fine aggregates. This study aims at investigations the possibility of the usage of these construction and demolition wastes to produce the fresh concrete with desirable properties. Natural fine aggregates (river sand) are replaced by the recycled fine aggregates by the different percentage levels for the production of fresh concrete. A comparative interpretation on the strength characteristics of the concrete produced with Ordinary Portland Cement and Portland Pozzolana Cement is also presented and discussed in this paper. © Springer Nature Singapore Pte Ltd. 2019.Item Use of foundry sand as partial replacement of natural fine aggregate for the production of concrete(2019) Saha S.; Rajasekaran C.; More A.P.The scarcity of natural fine aggregate becomes prominent in the present scenario due to high consumption of natural fine aggregate as the demand for concrete is increasing day by day. As a result, environmental degradation also becomes very significant. In this experimental study, an effort has been made to study the feasibility of using foundry sand as partial replacement for natural fine aggregate to produce concrete with desired properties. Physical and mechanical properties of the produced concrete were studied by incorporating foundry sand, 10, 20, 30, and 40% of the mass of total fine aggregate in the mixes. For achieving the desired strength of concrete mixes, 30% replacement of natural fine aggregates by foundry sand was observed in this work to be considered for the production of fresh concrete. Use of certain percentage of foundry sand as alternative for natural fine aggregate to produce concrete will lead to protect the natural resources, save the environmental system, and promote sustainability in concrete industries. © Springer Nature Singapore Pte Ltd. 2019.Item Sustainable building management by using alternative materials and techniques(2019) Thanu H.P.; Kanya Kumari H.G.; Rajasekaran C.Nowadays house construction is the basic need all over the world. Since the conventional building materials are causing degradation of the environment and also inadequate, it must be replaced by alternative building materials which are environment friendly or efficient. The mining of popular fine aggregates and quarrying of coarse aggregate results in depletion of hard rock and environmental imbalance. In view of this, there is need for developing alternative material. In most industrialized countries, the building sector accounts about one-third of total energy consumption. In order to ease this problem radical improvement is employed in building energy efficiency management. The framework design is in such a way so that it can balance between the issues such as environmental, economic and social issues. This is achieved by altering the construction method and materials used for any conventional building. The objective is to promote alternative materials to housing in such a way, that if compared with conventional materials it should prove to be an ideal alternative. Using alternative building materials save manufacturing cost, transportation, energy, time and these materials have high potential in replacing the conventional materials without compromising the strength and durability. Use of alternative technology is advantageous as it uses the locally accessible raw materials, waste products obtained from industry, etc. In this study, we have considered conventional building materials with alternative building materials by taking a residential project of 2340 SFT (including ground and first floor) and an industrial project of 3100 SFT. The cost reduction is found to be 20.17 and 18.19% in residential building and industrial building respectively hence ensuring that they are cost-effective and energy-efficient. Similarly, the reduction in embodied energy consumption is found to be 38.72% in residential and 17.78% in industrial building which shows that the utilization of alternative materials in construction ensures the building as eco-friendly. © Springer Nature Singapore Pte Ltd. 2019.