K. Sivasubramanian and P.K. Umesha
Damages occur in all structures due to several reasons. Research in the area of damage detection has been of interest to the researchers for several years. Damage detection…
Abstract
Damages occur in all structures due to several reasons. Research in the area of damage detection has been of interest to the researchers for several years. Damage detection methods help in early detection and hence early repair and rehabilitation of structures. In this paper, a graphical method has been implemented to detect and quantify the damage. Further, in this work, the method has been generalised to solve the damage detection in all beam structures, independent of variations in geometric or material characteristics of the structural system. The frequencies are non‐dimensioned as frequency ratios and are used in the studies. Detailed studies have been performed to arrive at the generalised method. The abilities of the method have been highlighted using the numerical simulation results.
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Hassan Samami and S. Olutunde Oyadiji
The purpose of this paper is to employ analytical and numerical techniques to generate modal displacement data of damaged beams containing very small crack-like surface flaws or…
Abstract
Purpose
The purpose of this paper is to employ analytical and numerical techniques to generate modal displacement data of damaged beams containing very small crack-like surface flaws or slots and to use the data in the development of damage detection methodology. The detection method involves the use of double differentiation of the modal data for identification of the flaw location and magnitude.
Design/methodology/approach
The modal displacements of damaged beams are simulated analytically using the Bernoulli-Euler theory and numerically using the finite element method. The principle used in the analytical approach is based on changes in the transverse displacement due to the localized reduction of the flexural rigidity of the beam. Curvature analysis is employed to identify and locate the structural flaws from the modal data. The curvature mode shapes are calculated using a central difference approximation. The effects of random noise on the detectability of the structural flaws are also computed.
Findings
The analytical approach is much more robust in simulating modal displacement data for beams with crack-like surface flaws or slots than the finite element analysis (FEA) approach especially for crack-like surface flaws or slots of very small depths. The structural flaws are detectable in the presence of random noise of up to 5 per cent.
Originality/value
Simulating the effects of small crack-like surface flaws is important because it is essential to develop techniques to detect cracks at an early stage of their development. The FEA approach can only simulate the effects of crack-like surface flaws or slots with depth ratio greater than 10 per cent. On the other hand, the analytical approach using the Bernoulli-Euler theory can simulate the effects of crack-like surface flaws or slots with depth ratio as small as 2 per cent.
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Noriza Revaula Tibon and Raniel Mejia Suiza
Structures such as buildings are at risk to the natural hazards such as earthquakes. Damage and loss of these structures may cause not just human lives but cultural heritage to be…
Abstract
Purpose
Structures such as buildings are at risk to the natural hazards such as earthquakes. Damage and loss of these structures may cause not just human lives but cultural heritage to be lost as well. This study aims to look into the exposure and vulnerability that deal with how many historic buildings there are in Metro Manila, how they are classified and how susceptible these buildings are to damage because of a certain amount of ground motion.
Design/methodology/approach
Inventories for exposure were conducted according to structural material, height and vintage. The building typologies of HAZARDS US Multi-hazard and UPD Institute of Civil Engineering were used and modified in this study. Three buildings, specifically the Central United Methodist Church (CUMC), Ellinwood Malate Church and Ermita Church, were modeled and analyzed with the aid of ETABS. Using the performance points and capacity curves derived from the nonlinear analysis, vulnerability was quantified by coming up with a vulnerability curve that expresses damage as a function of ground motion.
Findings
It was concluded that there are 54 historic buildings present in Metro Manila as of 2012. Reinforced concrete moment frames comprised the majority of historic buildings at 44.5 per cent of the population. Among the three buildings, CUMC responded as the strongest and Ermita Church responded as the weakest.
Originality/value
This paper fulfils the need to quantify the seismic exposure and vulnerability of the historic buildings in Metro Manila, as the more vulnerable these structures are, the more they need to be strengthened against potential hazards.
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Umesha Sasanthi Weerapperuma, Akila Pramodh Rathnasinghe, Himal Suranga Jayasena, Chamitha Sanjani Wijewickrama and Niraj Thurairajah
A novel facet of the construction industry's (CI) digital transformation relates to the rise of smart contracts, and the contribution of blockchain technology in this domain…
Abstract
Purpose
A novel facet of the construction industry's (CI) digital transformation relates to the rise of smart contracts, and the contribution of blockchain technology in this domain appears to be nascent but rapidly gaining traction. Although the benefits of digitalisation for technologically less enthusiastic CI are irrefutable, the adoption of smart contracts has been found to be low pertaining to industry professionals' behavioural factors stimulated by technological perception. The challenge undertook by this study, therefore, is to develop a knowledge framework for blockchain-enabled smart contract adoption in the CI.
Design/methodology/approach
From a methodological perspective, this study employed a qualitative approach that involved semi-structured interviews with ten (10) highly experienced CI practitioners involved in digital innovations for data collection. Directed content analysis was performed using NVivo 12 software, which enabled the creation of preliminary open codes. Subsequently, these open codes were grouped into similar categories to develop axial codes. Finally, the study presented final themes along with their corresponding descriptions.
Findings
Notably, research findings expanded the current body of knowledge on perceived attributes and their measurement items to determine the perception of innovation adoption in CI, where a total of nine (9) perceived attributes were associated with thirty-two (32) measurement items.
Originality/value
The measurement items were seen as having an extensive impact on the CI professionals' decision to adopt blockchain-enabled smart contracts. With ensuing implications, this study represents one of the first to present a knowledge framework exclusively customised for blockchain-enabled smart contracts, laying the groundwork for effective technological adoption by CI professionals.
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Alex Osei Afriyie, Ebenezer Kofi Howard, Benjamin Kwablah Asinyo, William Badoe, Raphael Kanyire Seidu and Edward Apau
The purpose of this study is to develop a system that detects warp breakage in manual looms using simple mechanisms combined with electronic circuitry.
Abstract
Purpose
The purpose of this study is to develop a system that detects warp breakage in manual looms using simple mechanisms combined with electronic circuitry.
Design/methodology/approach
This study used the universal design methodology model where results from observations and interviews aided in designing the appropriate blueprints for the mechanism.
Findings
Testing procedures revealed that the conductivity of steel bars coupled with the weight of the droppers affected the efficiency of the mechanism. Additionally, the weight of the drop wires influenced the rising of the warp threads during shedding. Considering this, a plate thickness of 0.06 mm was ideal for the droppers which did not affect warp shedding. Test outcomes at the weaving shed proved the workability of the mechanism for timely or prompt repair of a broken warp by weavers that ensured fabric quality.
Originality/value
The issue of warp breaks remains a critical problem at weaving on manual looms which influence the quality of fabrics. These looms are used by craftsmen in producing interesting fabrics for the market of which they depend on for their living. Premise on this, a two-way (light + sound) alert system was developed to assist weavers to effectively locate and repair broken yarns. Additionally, weavers with special needs (blind people) would be notified on a warp break for immediate repair from someone. This would limit the unnecessary challenges associated with broken warp yarns during weaving.
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Jayaprakash Reddy Joga and Varaprasad B.J.S.
Nowadays, application of biopolymers on geotechnical engineering works is booming to avoid the harsh effects on environment by using conventional methods for soil treatment. In…
Abstract
Purpose
Nowadays, application of biopolymers on geotechnical engineering works is booming to avoid the harsh effects on environment by using conventional methods for soil treatment. In this present study, xanthan gum (XG) is used as a biopolymer to improve dispersive properties of the soils because these soils are easily prone to erosion, which may lead to the damage of many hydraulic structures.
Design/methodology/approach
In the present study, attempts are made to reduce the dispersive potential and increase the Strength and erosion resistance by treating the soils with various percentages of XG (0.5%, 1%, 1.5% and 2%). To assess the dispersive potential and erosion resistance of soils, tests such as double hydrometer test, pinhole erosion test, crumb test and cylinder dispersion test were conducted. Further tests were expanded for its geotechnical characteristics such as Atterberg’s limits, standard proctor test, unconfined compressive strength test, one-dimensional consolidation for various curing days. Scanning electron microscopy analysis was also carried out to know the microscopic view towards its particle orientation and bindings. Chemical tests such as sodium absorption ratio, total dissolved solids (TDS) and percentage sodium (PS), electronic conductivity and pH tests were also conducted.
Findings
The results revealed that there is a reduction in the dispersive potential of XG treated soils for all the combinations. Addition of XG decreased the PS in the soil as a result dispersivity of soil decreased. Strength and erosion resistance of soil increased with the addition of XG and 1% XG was observed to be the optimum percentage for stabilizing these types of soils.
Practical implications
These results will be very much helpful for engineers when they come across with dispersive soils for better handling and management.
Originality/value
The originality of this study was an attempt towards sustainable development by treating dispersive soils with XG and effects on various geotechnical and dispersive characterizes.
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This paper aims to evaluate the progress made in achieving sustainable development goal-2 (SDG 2) in India, with a focus on ending hunger, ensuring food security, improving…
Abstract
Purpose
This paper aims to evaluate the progress made in achieving sustainable development goal-2 (SDG 2) in India, with a focus on ending hunger, ensuring food security, improving nutrition and promoting sustainable agriculture. The assessment uses data from SDG Index reports, which offer a comprehensive overview of the advancements made by 28 states and 8 union territories (UTs) in India.
Design/methodology/approach
The evaluation is based on information derived from three editions of the SDG Index reports, initially published in 2018 and subsequently in 2019 and 2020. These reports provide a detailed analysis of the status and achievements of different states and UTs in relation to SDG 2. The categorization of states and UTs into aspirant, performer, front runner and achiever categories serves as a crucial framework for assessing the progress.
Findings
Despite concerted efforts by India, the majority of states and UTs are positioned in the aspirant and performer categories, suggesting that significant challenges persist in achieving SDG 2 targets. The results emphasize the necessity for stronger measures to elevate states and UTs to the categories of front-runners and achievers. The persistent challenges of malnutrition, hunger and their economic ramifications require immediate and strategic interventions to address these pressing concerns.
Originality/value
This paper contributes to the existing literature by providing a comprehensive analysis of the progress towards SDG 2 in India, using the insights from the SDG Index reports. The categorization framework used in this assessment offers a nuanced understanding of the challenges faced by different regions, highlighting the original contribution of this study. The findings underscore the urgency of targeted efforts to address malnutrition, hunger and related issues, emphasizing the importance of sustained commitment to achieving SDG 2 for the overall well-being of vulnerable populations.
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Reza Ghazavi and Haidar Ebrahimi
Groundwater is an important source of water supply in arid and semi-arid areas. The purpose of this study is to predict the impact of climate change on groundwater recharge in an…
Abstract
Purpose
Groundwater is an important source of water supply in arid and semi-arid areas. The purpose of this study is to predict the impact of climate change on groundwater recharge in an arid environment in Ilam Province, west of Iran.
Design/methodology/approach
A three-dimensional transient groundwater flow model (modular finite difference groundwater FLOW model: MODFLOW) was used to simulate the impacts of three climate scenarios (i.e. an average of a long-term rainfall, predicted rainfall in 2015-2030 and three years moving average rainfall) on groundwater recharge and groundwater levels. Various climate scenarios in Long Ashton Research Station Weather Generator were applied to predict weather data.
Findings
HadCM3 climatic model and A2 emission scenario were selected as the best methods for weather data generation. Based on the results of these models, annual precipitation will decrease by 3 per cent during 2015-2030. For three emission scenarios, i.e. an average of a long-term rainfall, predicted rainfall in 2015-2030 and three years moving average rainfall, precipitation in 2030 is estimated to be 265, 257 and 247 mm, respectively. For the studied aquifer, predicted recharge will decrease compared to recharge calculated based on the average of long-term rainfall.
Originality/value
The decline of groundwater level in the study area was 11.45 m during the past 24 years or 0.48 m/year. Annual groundwater depletion should increase to 0.75 m in the coming 16 years via climate change. Climate change adaptation policies in the basin should include changing the crop type, as well as water productivity and irrigation efficiency enhancement at the farm and regional scales.