Ship Building Infrastructure Application of Steel Sheet Pile for Closing the face of Ship Side Launching Wharf
Chandrakant Gokhale
Purpose : The ship launching is most important and critical activity in ship manufacturing. The side launching of ships is being increasingly adopted worldwide and so in India. This requires design and construction of wharf for side launching of ships. The wharf design for ship launching differs is some aspect with that of wharf for passenger or cargo operations. In addition to loading configuration the two main differences between ship side launching wharf are arriving at various levels and closing the face of the wharf. While wharf the face of the wharf may be kept open or closed based on environmental and other conditions for a passenger or cargo wharf, for a ship side launching wharf it is essential to close the face of the wharf for safety of the ship as well as wharf. Study design/methodology/approach : In this study an attempt is made to arrive at various wharf levels viz. floor finish level, ship launching levels dredging levels etc. based on functional and operational requirement, safety as well as economy and ease of construction in addition to tidal levels at shipyard. The study presents in detail the process of stability, design and construction aspects in detail for closing the face of the wharf with application of z-section steel sheet piles. Findings : The study indicate that arriving at various levels for ship side launching wharf has considerable impact on function, operation in addition to construction. The z-section steel sheet pile is found to be effective for closing the face of the wharf having ease and faster construction and that it can be integrated with main piles of the RCC wharf. Originality/value: Normally sheet piles are procured based on the design required to close the face of ship side launching wharf. This study is original and has great value in the sense that it made the use of available sheet pile (which were not suitable as per conventional design requirement). With design modifications they were successfully integrated with the wharf piles to transfer extra load. RCC Research limitations/implications: The limitation of the study can be considered that it is site specific and replicating at other site will depend on soil profile and properties of that site.
Impact of Common Local Building Materials of Typical Indian Villages in Controlling Indoor Temperatures on Exposure to Direct Solar Radiation
M. Govinda Krishna and A. J. Krishnaiah
Purpose : Sustainable construction practices aim at reducing the use of natural resources, decrease waste and pollution, increasing the energy efficiency, and promote the use of renewable energy sources. It focusses on improving healthier indoor environments, improving air quality. Sustainable construction practices can create economic benefits by reducing long-term operating costs, improving the value of buildings, etc., Study design/methodology/approach : In the study, a single room model house was constructed to compare the 'thermal efficiencies' of local building materials. A digital data logger connected with eight K-Type 'thermocouples' along with a computer was used to record the temperatures. Findings : “Time lag” and “decrement factors” serve as parameters in 'thermal analysis' to characterize the heat transfer properties of building materials and insulation systems. Both parameters are influenced by 'thermal conductivity', density, and heat capacity of the material. It is found, brick sample has the maximum “time lag”, followed by granite, followed by laterite and then cement block, the “Decrement Factor” being almost same. Originality/value: The work was carried out at Bayar Village of Kasaragod district of Kerala state (Latitude: 12°41'4” N, Longitude: 75°0'44” E) during December 2021 to April 2022. The average temperature variation during this period over a day is found to be 23°C to 38°C, while that of the nation is 24°C to 38°C. Readings were recorded across one single material type in one setup. Procedure was repeated for the remaining three building materials also. Research limitations/implications: The research findings do not reflect the 'thermal conductivity' of the materials as such and also generalized conclusions cannot be drawn from the results as the properties of the ingredients can vary from place to place.
Time lag; Decrement factor; Global Warming; Green House Gases; Laterite
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Research Articles
Project Management Principles and Practices: Findings from Indian Smart City Projects
Tushar Jadhav and Rahul Deshpande
Purpose : The smart cities mission to develop 100 smart cities in India is indeed an ambitious project launched by the Government of India. Therefore, for such ambitious project, the role of project management practices assumes key significance. The main emphasis of this study is to investigate the role of project management principles and practices in planning and coordination of these smart cities. Study design/methodology/approach : This paper reviews the various initiatives proposed for smart cities in India and makes the comparative analysis of few smart cities from the dimensions of project management. The first part of the study provides a qualitative evaluation in terms of mission / project benefits which will be accrued through execution of the project. The second part of the study outlines the practices followed through in execution projects, based on interactions with experts and published information. In the third and the last part of this study, we recommend a preferred course of action for the delivery of smart city projects. Findings : The study indicated a significant improvement in the way the smart cities are handled in terms of projects. However, the higher authorities involved in planning and execution of smart cities in India need to have a comprehensive approach towards selection of projects, project prioritization, project financing structure and project delivery mechanism. The respondents indicated the need for improving the project management process during planning and executing smart city projects. Originality/value: This paper provides a systematic understanding on the project management practices followed in planning and executing smart cities in India. The lessons learned that are compiled in this study, will certainly help the relevant stakeholders in effective and efficient management of upcoming smart cities in India.
Baselining Labour Productivity of Structural Activities in Small Scale Residential Construction
Sreya Prasad
Purpose : The study is intended to identify reliable baselines for labour productivity of various structural activities in residential construction. In order to monitor the productivity of construction activities on a day-to-day basis across projects, understanding and standardizing productivity of activities is crucial. Though monitoring labour productivity is of great value, empirical evidence showing baselining labour productivity is significantly less in literature. Study design/methodology/approach : Quantitative statistical analysis is done for bench marking the productivity numbers and qualitative analysis is done to analyse the performances at various sites. The outliers in each data set are identified using Median Absolute deviation (MAD). The refined data is then analysed to identify the central tendency of labour productivity. Findings : These statistically identified baseline numbers are intended to be used in the industry to analyse labour performances across residential projects on a real time basis and make improvements as the productivity impacts the cost performance, resource allocation, budget estimation of the project. Research limitations/implications: The study is limited to identifying baselines. One of the drawback of the study is the idle time of labour was not captured in the study. Also the reason for poor performance in some sites and better performance in other sites also makes a scope for further study.
Baseline; Structural Activities; Continuous Improvement; Labour Productivity; Median Absolute Deviation; Median; Residential Buildings; Cast in Situ Construction
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Research Articles
Machine Learning Algorithms to Predict Compressive Strength of Reinforced Concrete using Rebound Number Index
Bharti Tekwani and Archana Bohra Gupta
Purpose : Non Destructive Technique (NDT) is the key to monitoring compressive strength of structural concrete used in construction and rehabilitation works. During past decades, several NDT methods had been invented for the strength assessment of concrete. Amongst these methods, the Schmidt Rebound Hammer (RSH) has been a popular and quick method for strength assessment using suitable regression equations. The performance of regression methods can be improved by using machine learning (ML) algorithms. Soft computing techniques viz. ML algorithms have been globally embarked and have enabled the development of tools to evolve essential skills on supervised regression models which gives practical knowledge to Artificial Intelligence (AI) applications in order to deal with real world engineering problems. Instead of applying conventional regression models to correlate data; researchers are developing new perceptron in ML which eliminates feature extraction that involves complexity of problem with huge number of data having more variables. Study design/methodology/approach : In this experimental study, an attempt has been made to create and apply Artificial Neural Network (ANN) model, Adaptive Neuro Fuzzy Inference System (ANFIS) model and statistical model to prognosticate the correlation equations for compressive strength ( ) of reinforced cement concrete (RCC) obtained by destructive fc and nondestructive testing. The obtained data in experimental study includes variation of nominal concrete cover as 20mm, 25mm and 40mm. For assessing the effectiveness of ANN under experimental data obtained in laboratory, ANN model was activated under “Leaky Rectified Linear Unit (ReLU)” function and generalized equation was formed theoretically by using weights obtained from ANN regression models in Matlab programming and the errors viz. root mean square and coefficient of determination (R ) were determined. (J) 2 The comparative study was performed between fc values computed by ANFIS model, ANN models and linear or nonlinear statistical regression models. Value: The reason of finding out correlation equation specifically for RCC is that rebound number values obtained will be higher for reinforced concrete in comparison to that for plain concrete, if the hammer strikes on a location where there is a steel bar within. In such a case, the compressive strength values of concrete obtained by rebound number will be apparently higher than the actual strength. So, when R is performed in field, first the rebars are SH required to be located using a scanner so that the rebound hammer does not strike at a location where there is a rebar beneath. This increases the working time. Else, suitable correction factors are required to be applied to obtain the corrected values of of concrete. Hence, this study is taken up to obtain the correlation equations fc between destructive and nondestructive test values for RCC so that these equations can be used directly without the need of a correction factor in case of NDT of RCC elements. Findings : For assessing the adequacy of ANN under experimental data obtained in laboratory, ANN model was activated under “Leaky Rectified Linear Unit (ReLU)” function and generalized equation was formed theoretically by using weights obtained from ANN regression models in Matlab programming and the errors i.e. root mean square , coefficient of determination (R ) were calculated. A comparative study was conducted between (J) f 2 c values computed by ANFIS model, ANN models and linear or nonlinear statistical regression models. Research limitations/implications: Temperature fluctuations, variation in source of aggregates, cement type; compaction effort etc. can influence the rebound hammer readings; however the effect of each of these specific scenarios have not been considered in the present study considering that their effect will be negligible for the specific aims of the study performed.
ANN; ANFIS; Conventional Concrete; Correlation Equation; Rebound Number
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