SCITECH Nepal

Effect of Steel Jacketing Thickness on Seismic Performance of Bridge

Rajan Suwal, Binaya Jamarkattel — Wed, 13 Dec 2023 00:00:00 +0000

The bridges of Nepal are getting older and old bridges were designed without considering the seismic forces, hence have low seismic capacity. The capacity of these bridges needs to be enhanced and should perform well during seismic events. The jacketing technique can be used to upgrade the bridge's structural performance. This research paper mostly focuses on the seismic performance enhancement after the application of steel jacketing on the bridge pier. The variable that has been varied is the thickness of the steel jacket. The capacity of a bridge pier is evaluated using displacement-controlled nonlinear static analysis (Pushover). The time history load is applied to the structure to determine the seismic demand of the bridge. The quantification of the enhancement of the bridge structure after the application of Steel Jacketing is evaluated by plotting the fragility curve. The modeling of the bridge is done in CSI Bridge V20.2.0. The different damage state is defined using the strain values obtained from the pushover analysis. For different damage states, the capacity and demand value are used to obtain the probability of exceeding at different PGA levels. The fragility curve is developed using the First Order Second Order Method (FOSM). From the study, it is found, that the vulnerability of the bridge after the use of jacketing for extensive damage state, the probability of failure reduced from 28.22% to 14.24% at 1.0g PGA. Similarly, the vulnerability of the bridge after the use of jacketing for collapse damage state, the probability of failure decreased from 16.93% to 7.22% at 1.0 PGA

Behavior And Optimum Location Of Outrigger And Belt Truss System In High-Rise Buildings Subject To Seismic Loading

Sunil Khadka, Thaman Bahadur Khadka, Rabi Thapa Magar, Bikram Rawat — Wed, 13 Dec 2023 00:00:00 +0000

This study is focused on the efficient use of the lateral load-resisting system for high-rise concrete buildings subjected to earthquake load. 32-storey three-dimensional models of OMRF, SMRF, core, core with outrigger (OT), core with outrigger and cap truss, and core with belt truss (BT) and core with belt truss and their cap truss systems are analyzed and compared to find the lateral displacement, storey drift and time-period reduction. The modelling and analysis were performed using finite element software ETABS 2016. The analysis has been carried out to study the effect and performance of the outrigger system and belt truss system in the building. These systems are provided at different levels along the height of the building. The coverage of the outrigger and belt trusses are equal to the height of the typical story and maintained the same in all the models. For finding the optimum position of the outrigger and belt truss system and also with their cap truss, the result is illustrated in terms of the reduction of top-storey lateral deflection, the maximum reduction in storey drift and the maximum reduction in the time period of the building. All the parameters are obtained for the structure without an outrigger system and they are compared with the values obtained by introducing an outrigger and belt truss. A total of 51 models are studied for finding the optimum location and behaviour of the systems when introduced on the building. A comparison is made to find the best system among all the systems, which are introduced in the model. Among the entire systems, an outrigger with a belt truss is found to be the best system in terms of reducing deflection, drift, time and base shear. The optimum position is found to be at 0.375 times the height of the total structure when the user system is outrigger and its belt system in terms of reduction in deflection and time, whereas the optimum position is at mid-height when the selection criterion is lateral drift.

How Effective Is Inter-Basin Transfer to Manage Temporal Variation Of “Too Much” And “Too Little” Water Conditions for Irrigation in a Himalayan Basin?

Utsav Bhattarai, Laxmi Prasad Devkota, Tek Maraseni — Wed, 13 Dec 2023 00:00:00 +0000

Better irrigation facilities leading to “more crop per drop” are today’s needs. This study examines how the overall water balance of Sunkoshi, Marin, and Bagmati Basins will be altered by implementing the Sunkoshi-Marin Diversion Project (SMDP) to fulfill the unmet demands of the Bagmati Irrigation Project (BIP) in the Bagmati Basin via the Marin Basin in Nepal. The specific objectives are to: i) quantify “too much” and “too little” water peculiar to the study basin based on historical data; ii) evaluate water availability, irrigation water requirement, and deficits with and without SMDP; and iii) provide evidence-based recommendations on the effectiveness of the SMDP considering hydropower generation, irrigation and low- and high-flow conditions. Thirty years of historical daily flow data (two gauging stations) and precipitation data (15 stations) were obtained from the Department of Hydrology and Meteorology. Other spatial input data were acquired from relevant authorized sources. Water availability has been estimated using flow at the diversion sites while the irrigation requirements have been calculated based on secondary information. Results show that additional water is not at all required for Marin and Bagmati Basins in the monsoon season. Rather, the diverted water increases the flood hazard. Moreover, the contribution of hydropower from SMDP to the national energy demand is insignificant in the monsoon. However, the SMDP was found to play an important role in meeting the irrigation deficits during the dry season. Its contribution to hydropower production in the lean period is also commendable. However, the proposed irrigation requirement of the BIP cannot be met even after the implementation of the SMDP. More importantly, there is a high probability of the intended diversion flow not being available in the Sunkoshi River (donor) which could have severe consequences downstream. Therefore, additional options for conjunctive use need to be explored.

Critical Success Factors of Agile Software Development - A Systematic Literature Review

Trailokya Raj Ojha — Wed, 13 Dec 2023 00:00:00 +0000

Agile software development has gained more popularity due to its capacity to manage constantly changing needs and generate high-quality software in less time. However, several success factors are required for an agile project to succeed. Agile development technique, delivery strategy, project team training, customer and staff involvement, management commitment, organizational culture, communication, and project management process are critical success factors (CSF) discovered in this study. This study's goal is to locate and evaluate these crucial elements of the agile software development methodology's success. A systematic literature review was conducted to study and analyze the previous studies to identify the CSFs in agile development. The findings of the literature review indicate that technical, people, organizational, and process factors are crucial for the success of agile projects. Each CSF falls into any one of these factors. Overall, this study's findings emphasize the significance of CSFs in the agile software development process. Organizations and software development teams can enhance their agile processes and raise the likelihood of project success by being aware of these aspects. Teams may create high-quality software in less time while simultaneously fulfilling the goals and expectations of the customer by concentrating on different success factors.

A Case Study on the Effect of Geometric Design Consistency on Road Crashes on Narayanghat-Muglin Road Section

Bharat Prashad Banjara, Gopal Gautam — Wed, 13 Dec 2023 00:00:00 +0000

Design consistency is overlooked while designing roads, resulting in unsafe road facilities. The safety performance of a highway can be greatly enhanced by detecting and addressing any inconsistencies present on the road. Over time, the application of geometric standards shifted from new road construction to upgrading, which could result in limited design options. Due to the emerging importance of design consistency in geometric design, this research has been initiated to evaluate horizontal curve consistency based on an established operating speed prediction model.

Horizontal curve data of the Narayanghat–Mugling Road section has been collected from the Division Road Office, Bharatpur, and accident data has been obtained from the District Traffic Police, Chitwan. Out of 242 horizontal curves in the Narayanghat-Muglin road section, the design consistency of 223 horizontal curves was evaluated, while 19 horizontal curves with posted speed limits were not considered because these curves are not within the range of design criteria set out in Asian Highways Design Standards (1993).

The average, maximum, and minimum 85^th percentile speed was found to be 78, 101, and 32 kmph respectively. Out of 223 horizontal curves evaluated for individual consistency based on operating speed, 75% of the curves were categorized as “poor”, 16% as “fair”, and 9% as “good”. It was found that under successive element consistency evaluation based on operating speed, 22% of horizontal curves were categorized as “poor”, 23% as “fair”, and 55% as “good”. When studied under vehicle stability consistency evaluation criteria, 88% of the curves were classified as “fair” and 12% as “good”. It was found that the predicted accidents caused by geometric design inconsistency and vehicle stability are 5.12% of total accidents per year.

From the safety standpoint, if the condition |V₈₅-V_d|>20 is met, critical discrepancies between the design speed and operating speed arise, resulting in unsafe operations. Therefore, it is generally advisable to consider redesigning those road sections.

Cost Comparison of Flexible Pavement on Weak Sub-Grade Soil Modified with Lime and SD

Braj Kishore Chaudhary, Gopal Gautam — Wed, 13 Dec 2023 00:00:00 +0000

The effectiveness of flexible pavement is affected by the subgrade quality. The subgrade refers to a compacted layer of soil that provides sideways support to the pavement. When constructed on a weak subgrade, it negatively impacts the pavement's performance, leading to a shorter lifespan. Traditionally, the common method to stabilize a soft subgrade involves removing the weak soil and replacing it with stronger soil. However, due to the high expenses associated with soil replacement, highway agencies are exploring alternative approaches to constructing highways on soft subgrades. Soil stabilization is a commonly employed alternative in pavement construction, serving as an effective method to enhance the engineering characteristics of soil, including its strength and stability. This paper focuses on the utilization of lime and stone dust (SD) as admixtures for an efficient ground improvement technique over weak subgrade soil deposits. The California Bearing Ratio (CBR) test is conducted by making the specimens of weak subgrade by adding the variable percentages of a mixture of lime and SD. First, the soil was mixed up with lime to 12% by weight with an increment of 3% again the soil was mixed with SD with increments of 10% up to 50% by weight of soil. The study determined an optimal lime content of 3% based on the geotechnical properties of the mixture and the cost considerations of lime and the weak subgrade. Following this, SD was added to the optimized lime-weak subgrade mixture in varying increments of 10% by weight, up to a maximum of 40%. The modified mixes were then evaluated for their CBR and maximum dry density values. The CBR is increased to 15% and the total pavement thickness decreased to 725 mm for 50% SD addition with 4.89 % in cost reduction.

Machine-Learning Based Prediction of Lung Cancer

Trailokya Raj Ojha, Menuka Maharjan — Wed, 13 Dec 2023 00:00:00 +0000

The incidence of lung cancer has now exceeded all other types of cancer globally, making it the leading cause of cancer-related deaths. Compared to other types of cancer, lung cancer has a poor prognosis and high mortality rate, making it challenging for humans to accurately predict its incidence rates. The goal of the study is to implement machine learning techniques for the early detection of lung cancer, which can increase patient survival rates. To find the most important factors and predict the possibility of lung cancer, a variety of data mining approaches, including logistic regression, k-means, and apriori algorithms are used in this study. Age, gender, smoking habit, and medical history are a few of the factors included in the dataset used for the study. The logistic regression classifier shows an accuracy of 95% for the classification of lung cancer in patients. The simulation results obtained from the k-means clustering algorithm shows that the main causes for the possible occurrence of lung cancer are chronic diseases, fatigue, allergy, wheezing, alcohol consumption habit, and breath problem. Similarly, according to the association rule's findings, there is no chance of lung cancer developing in a non-drinker who is free of peer pressure, allergies, and wheezing issues.

Assessment of Rainfall-Induced Shallow Landslides in Kavre District, Nepal

Suman Shrestha, Prachand Man Pradhan, Hari Krishna Shrestha — Wed, 13 Dec 2023 00:00:00 +0000

Steep slopes and fragile geology make Nepal a landslide-prone country. Kavre district experiences a large number of shallow landslides in the monsoon season. This research aims to establish rainfall intensity relation with rainfall duration along with rainfall threshold for the initiation of shallow landslides in the Kavre district, Nepal. The six rain gauge stations' rainfall data in the Kavre district from 1987-2016 and landslide data from 1987-2013 were used for establishing rainfall thresholds. The rainfall that risks the landslide event was sorted and the regression analysis of the rainfall and landslide yielded a relationship I =86.738 *D^-1.066 having a coefficient of determination R² = 0.1257. The analysis also incorporates the drawing of the lower boundary which is the 48-h rainfall depth that indicates the rainfall threshold for the initiation of landslide in the Kavre district. The 48-hour rainfall intensity and rainfall depth at which the risk of landslide initiation is high in the Kavre district is 1.4 mm/h. and 67.18mm. Analysis of the antecedent rainfall and the landslide occurrence event indicated that the daily rainfall at failure conditions is better correlated with 3 days of cumulative rainfall at failure than with 5, 7, 10, 15, and 30 days. The study is significant for rainfall-induced landslide disaster management.

Barriers to Implementing Safety Measures During COVID-19 Pandemic on Building Construction Projects in Nepal

Bhupesh Chanda, Dinesh Sukamani, Sudip Pokhrel, Sujan Nepal — Wed, 13 Dec 2023 00:00:00 +0000

The COVID-19 pandemic caused disruptions in building construction projects, with safety measures being a major concern for workers and the public. This study aims to assess the barriers to safety measures during the COVID-19 pandemic on building construction projects in Nepal. A total of 330 responses were collected from construction professionals in Nepal using a Likert scale. To ensure the data's suitability for factor analysis using Principal Component Analysis, Kaiser-Meyer-Olkin, Bartlett's Sphericity test, inter-component correlations, and Cronbach alpha scores for internal consistency were checked, and principal components were extracted. A 25-item safety barrier to safety measures in building construction projects during the COVID-19 pandemic was identified through an extensive review of the literature; six components were retained using Principal Component Analysis which represented the model of choice and explained 62.86 % of the data variance. The components were; inappropriate safety guidelines, psychological working pressure, inadequate hygiene monitoring and control, lack of safety awareness, improper working culture, and insufficient planning and scheduling. The internal consistency for the retained components was high; Cronbach α scores ranged from 0.72 to 0.796. “Inappropriate Safety Guidelines” was the most critical barrier to implementing safety measures during the COVID-19 pandemic in building construction projects, according to the rankings of the six identified components. It is recommended that construction professionals and regulatory bodies prioritize the development and adherence to robust safety protocols tailored to pandemic conditions. Regularly updating and reinforcing these guidelines will be crucial in safeguarding the health and well-being of workers while ensuring project continuity. Additionally, investing in thorough training and awareness programs can significantly mitigate this barrier's impact.

Microbial Quality Assessment of Fresh Sugarcane Juice in Retail Shops Inside Kathmandu Valley

Sila Subedi, Sudip Pokhrel, Era Tuladhar — Wed, 13 Dec 2023 00:00:00 +0000

This study aims to assess the microbial quality of fresh sugarcane juice sold in retail shops inside Kathmandu Valley, as there is limited information available on the safety of popular fresh juices like sugarcane juice, which can cause food-borne illnesses when improperly prepared, despite the known health benefits of consuming fresh fruits juices. Sixty fresh sugar cane juice samples were collected from selected thirteen areas inside Kathmandu Valley. Out of 60 samples, 42 samples were contaminated with bacteria. The quality of each sample was assessed by total plate count, total coliform count, yeast and mold count, and isolation of pathogenic bacteria. The isolated bacteria were identified based on biochemical characteristics. The pH of collected samples ranged from 4.33 to 6.34, acidity from 0.01% to 0.09%, and total soluble solids from 13 to 21⁰Brix. The mean bacterial count was 5.26 log₁₀ CFU/ml, the coliform count was 4.67 log₁₀ CFU/ml, and the yeast mold count was 4.94 log₁₀ CFU/ml. E. coli was present in 38.1%, Citrobacter freundii in 47.6%, and Salmonella species in 14.3% of the total sample. Vibrio cholerae was not detected. Gentamicin, Ciprofloxacin, and Ofloxacin were effective, while Ampicillin was less effective. The study found that sugarcane juice samples from shops in Kathmandu Valley have high levels of contamination, including a high microbial load and slightly acidic pH with high total soluble solid values. The bacterial isolates exhibited varied degrees of antimicrobial susceptibilities and resistances, and the contamination was attributed to poor hygienic conditions during juice processing and handling, possibly due to the use of poor-quality water and a lack of training on food hygiene and safety. These findings suggest potential health hazards for consumers of fresh sugarcane juice.

Performance evaluation of three grid-connected monocrystalline silicon solar photovoltaic systems in Nepal

Jeewan Shrestha, Nawraj Bhattarai — Wed, 13 Dec 2023 00:00:00 +0000

This study evaluates three grid-connected solar photovoltaic (PV) systems using four criteria: final yield, performance ratio, capacity utilization factor, and system efficiency. The PV systems were installed on the rooftop of the Nepal Telecom office at Sundhara, Pokhara, and Biratnagar. The generation data was collected through the web interface of the data logger installed at the sites. Long-term comparison (four years) of the plant at Sundhara and the same system comparison of plants at Pokhara and Biratnagar were performed. Long-term analysis of the plant at Sundhara found that the final yield decreased from 2.91 kWh/kW_p in 2019 to 2.21 kWh/kW_p in 2022. Similarly, the performance ratio decreased from 91.0% in 2019 to 67.3% in 2022, capacity utilization factor decreased from 12.1% in 2019 to 9.2% in 2022, and system efficiency decreased from 16.8% in 2019 to 12.5% in 2022. The same system installed at Pokhara and Biratnagar had slightly varied performance owing to the variation in meteorological parameters. The average air temperature at Biratnagar (26.7°C) was higher than at Pokhara (13.1°C) while the amount of solar radiation at Biratnagar was just higher by 4%. This led to the reduction of final yield by 9% at Biratnagar than at Pokhara as higher temperatures at Biratnagar caused more reduction in the power output from the solar panels. Finally, this study provides insights to researchers, PV installers, and panel manufacturers on the actual performance of grid-connected solar PV in Nepal.

COVID-19 Lockdown's Effect on Building Construction Projects in Kathmandu Valley Nepal

Kreeti Bajracharya, Dinesh Sukamani — Wed, 13 Dec 2023 00:00:00 +0000

This research intends to assess the critical factors as an effect of COVID-19 lockdown on selected building construction projects within the Kathmandu Valley in Nepal. The research identifies “Health and Safety risk management” as the most critical factor compared to the other critical components namely supply chain operation, contractual and construction financial market. This research focuses on utilizing systematic partial least squares structural equation modeling to assess the effect of COVID-19 lockdown. Further, it seeks to demonstrate the direct relationships between COVID-19 effects and the critical factors that have been affected as a result of the pandemic. The study considers these factors as essential components in assessing the overall impact of COVID-19. This study attempts to evaluate and examine the significant pandemic effects on building construction projects. Nepal-based construction firms, government agencies, and non-government organizations were surveyed to identify critical factors affected by COVID-19 in building projects. The quantitative design method of this study included the use of smart partial least squares structural equation modeling (PLS-SEM), one of the statistical tools. Information like the fundamentals of the project, its state, etc., have been considered. 104 valid responses were received out of 130 questionnaires distributed supported at less than 1 % significance level. The inner structural model analysis, with a highest value of 7.014 and a beta value of 0.474, highlights the significance of the relationship between safety and risk management factors and COVID-19 effect in building construction projects. This relationship stands out as highly significant when compared to other constructs examined in the study. The findings underscore the crucial role of safety and risk management practices in mitigating the effects of the pandemic on construction projects.

Assessment of Labor Management Practices in Private Group Housing Developers in Kathmandu Valley

Sachin Sapkota, Hari Mohan Shrestha — Wed, 13 Dec 2023 00:00:00 +0000

The construction industry is known for its labor-intensive nature, and companies must maintain high labor management standards to complete projects within time and budget. However, challenges related to labor management are common in the industry and can negatively impact project delivery times and costs. In Nepal, housing developers face the issue of not delivering projects on time, leading to increased costs. This study explores the current labor management practices, challenges, and remedial measures in the construction industry of Nepal, with a focus on housing developers in the Kathmandu Valley. The study collected data from 17 building projects using interviews and questionnaires and analyzed the data using the Relative Importance Index (RII) and Spearman's rank correlation coefficient. The findings indicate that labor management issues, including poor communication, planning, inadequate wages, occupational health and safety, labor policy, and unfair treatment, are major challenges faced by housing developers in Nepal. The study recommends implementing better employee staffing, performance evaluation, work environment, training, and compensation management to address these challenges. The results of this study offer insight into current labor management practices and potential solutions for housing developers in Nepal, contributing to the overall success of construction projects. Proper labor management can result in substantial savings in time and cost for construction projects, making this study relevant and valuable to researchers and practitioners in the construction industry. The findings of this research could have important implications for private housing developers in Nepal, as well as for the broader housing sector in developing countries facing similar challenges.

Editor’s Note

Hari Krishna Shrestha — Wed, 13 Dec 2023 00:00:00 +0000

Generation and sharing of knowledge gained through research activities is a fundamental basis of the development of science and technology. Publication of research papers in a peer-reviewed professional journal is a basic parameter of the achievements of scientists and technical human resources around the world; publication of original research papers is an undisputed method of sharing knowledge among the peers. Institutes like Nepal Engineering College has been providing a platform sine 1995 to the scientists and engineers by regular publication of SCITECH Nepal Journal, and thereby creating an avenue of sharing research experiences.

This issue of SCITECH Nepal Journal has attracted the more scientists and engineers from different universities and research institutes of Nepal to publish their research papers. The readers will find a large spectrum of interesting and useful disciplines covered in this volume of the Journal. The areas covered range from biology, organic chemistry to the emerging technological issues like the artificial intelligence, including the computer modeling of multistoried structures to find techniques to enhance seismic safety.

The paper contributors are the ultimate backbone and heroes of the success of SCITECH Nepal. The editorial board has done an excellent job to ensure quality of the published research papers. I am sure the readers of this volume of SCITECH Nepal will find the contents highly satisfying and worthy of their time invested in reading the papers.

Wish you all a very Happy New Year 2024.

Prof. Dr. Hari Krishna Shrestha
Chief Editor
November 2023