E V Kajal

Bio: E V Kajal is an academic researcher from National Institute of Technology, Karnataka. The author has contributed to research in topics: Breakwater & Geotextile. The author has an hindex of 1, co-authored 1 publications receiving 2 citations.

Spatio-temporal classification and prediction of land use and land cover change for the Vembanad Lake system, Kerala: a machine learning approach

Abstract: Land use and land cover (LULC) change has become a critical issue for decision planners and conservationists due to inappropriate growth and its effect on natural ecosystems. As a result, the goal of this study is to identify the LULC for the Vembanad Lake system (VLS), Kerala, in the short term, i.e., within a decade, utilizing three standard machine learning approaches, random forest (RF), classification and regression trees (CART), and support vector machines (SVM), on the Google Earth Engine (GEE) platform. When comparing the three techniques, SVM performed poor at an average accuracy of around 82.5%, CART being the next at accuracy of 87.5%, and the RF model being good at the average of 89.5%. The RF outperformed the SVM and CART in almost identical spectral classes such as barren land and built-up areas. As a result, RF-classified LULC is considered to predict the spatio-temporal distribution of LULC transition analysis for 2035 and 2050. The study was conducted in Idrisi TerrSet software using the cellular automata (CA)-Markov chain analysis. The model's efficiency is evaluated by comparing the projected 2019 image to the actual 2019 classified image. The efficiency was good with more than 94.5% accuracy for the classes except for barren land, which might have resulted from the recent natural calamities and the accelerated anthropogenic activity in the area.

Experimental Investigation of the Hydraulic Performance of Breakwater Structures with Geotextile Armor Units

Abstract: Geotextile sand containers (GSCs) gained popularity recently as a modern age coastal protection measure. Its usability as an ecofriendly alternative for traditional breakwaters overcomes issues such as scarcity and quarrying prohibition of natural rocks. The current work involves a 1:30 scaled physical experimentation on the hydraulic performance of an emerged, nonovertopping breakwater model with GSCs. Four configurations of GSC structures are analyzed for their runup, rundown, and reflection characteristics confining to wave parameters of Mangaluru. The study revealed that the reflection coefficient (Kr) for GSC structures could range from 0.26 to 0.69. In addition, reducing GSC fill percentage from 100 to 80 is found to be more effective (up to 64%) in reducing reflection, runup, and rundown rates, than altering GSC size. These results can serve as a practical guideline for designing GSC breakwaters.

Preliminary investigation on stability and hydraulic performance of geotextile sand container breakwaters filled with sand and cement

Abstract: Breakwaters are essential constructions providing tranquility to ports and harbour structures, when there is a lack of natural protection measures. Traditionally these massive structures are constructed using natural rocks weighing tonnes. In the present scenario, obtaining huge natural rocks are difficult as well as non-eco-friendly. Geotextiles sand containers (GSCs) emerges as a suitable alternative for the rock armour units of breakwaters and various literatures supports its efficacy. The present investigation aims at analysing the performance of GSCs when filled with a calculated amount of cement and sand. The Hydraulic performance and stability analysis of cement and sand filled geotextile breakwater models are carried out in a 1:30 scaled monochromatic wave flume. When GSC breakwaters are filled with sand and cement, up to 43% increased stability is observed with a considerable decrease in wave runup, rundown and reflection, than sand-alone filled units. As a result, cement-sand filled GSC units can be suggested as a possible alternative to sand alone filled units where vandalism has to be countered.

A Non-conventional Durability Test for Simulating Creep of Geosynthetics Under Accelerated Degradation

Abstract: The evaluation of the durability of geosynthetics for application in real structures is an important field of investigation. Within this field, the interaction between degradation agents that geosynthetics can be subject to, in their different applications, is an increasingly studied issue, because it can have direct implications in the design of the materials. Thus, this article explores a non-conventional test for geosynthetics, to simulate creep under accelerated conditions using a saturation and drying procedure simultaneous to the creep process. In this way, the material is closer to the exogenous field conditions as in, for example, riverside projects or even in coastal protection. For this, a total of 48 tests of conventional creep and under accelerated degradation conditions were carried out in 4 different geotextiles. From these tests, models were proposed and presented coefficients of determination greater than 0.84. Additional results indicate an increased strain rate ranging between 5 and 16 times in creep test from the moment that degradation simultaneous with creep is induced. Reduction factors greater than 3 indicated a very aggressive degradation process. In general, the study showed that ensuring the design life of geosynthetics calls for a simulation of degradation conditions that demand more from these materials. By enabling a more precise analysis of field conditions the creep test under accelerated conditions presents an excellent tool for project design. The significance of this study for geosynthetics design is in providing general knowledge of creep under accelerated conditions using equations and models to determine important geosynthetic parameters.