Browsing by Author "Ragavan, P"

Now showing 1 - 4 of 4

item: Conference-Full-text
Effect of dynamic compaction on the compressibility characteristics of municipal solid waste, under the saturated and unsaturated conditions
(IEEE, 2022-07) Rathnayaka, A; Ragavan, P; Kulathilaka, A; Rathnayake, M; Adhikariwatte, V; Hemachandra, K
The scarcity of land suitable for new developments in urban areas is a growing problem in many countries. In Sri Lanka, open dumping has caused unsanitary landfills within major cities, and it is economically, socially, and environmentally desirable to rehabilitate them. Ground improvement is a significant step in the rehabilitation of landfills, and dynamic compaction (DC) is a commonly used method in treating heterogeneous fill materials such as municipal solid waste (MSW). In this study, MSW samples obtained from the Meethotamulla landfill site, Sri Lanka, subjected to DC under both saturated and unsaturated conditions, were tested using the Rowe cell apparatus. Their compressibility characteristics were established under four conditions: saturated-compacted, saturated-noncompacted, unsaturated-compacted, and unsaturated-noncompacted. The results of the analysis indicated that the improvement of density and compressibility characteristics of MSW due to DC is greater under the unsaturated condition. In addition, the results were compared with that of preloading. It was found that preloading is more effective in improving the compressibility of MSW under both saturated and unsaturated conditions.
item: Conference-Full-text
Effect of dynamic compaction on the compressibility characteristics of municipal solid waste, under the saturated and unsaturated conditions
(IEEE, 2022-07) Rathnayaka, A; Ragavan, P; Kulathilaka, A; Rathnayake, M; Adhikariwatte, V; Hemachandra, K
The scarcity of land suitable for new developments in urban areas is a growing problem in many countries. In Sri Lanka, open dumping has caused unsanitary landfills within major cities, and it is economically, socially, and environmentally desirable to rehabilitate them. Ground improvement is a significant step in the rehabilitation of landfills, and dynamic compaction (DC) is a commonly used method in treating heterogeneous fill materials such as municipal solid waste (MSW). In this study, MSW samples obtained from the Meethotamulla landfill site, Sri Lanka, subjected to DC under both saturated and unsaturated conditions, were tested using the Rowe cell apparatus. Their compressibility characteristics were established under four conditions: saturated-compacted, saturated-noncompacted, unsaturated-compacted, and unsaturated-noncompacted. The results of the analysis indicated that the improvement of density and compressibility characteristics of MSW due to DC is greater under the unsaturated condition. In addition, the results were compared with that of preloading. It was found that preloading is more effective in improving the compressibility of MSW under both saturated and unsaturated conditions.
item: Thesis-Full-text
Urban design implications for facilitating effective use of urban nature for user relaxation: case of small urban parks in Batticaloa
(2021) Ragavan, P; Wijesundara, J
The urban nature setting is a significant contributor to the wellbeing in the urbanization places, and it ought to be combined with the public realm. The town, for an example, Batticaloa consists of a public boom on the way of concentrating on the development in the urban areas as they become high denser. The bigger density decreases in the environmental place; however, it gives a chance to design the common places and effective places that provided their people with some contacts through natural environment. That theory gives appearance to the potentials of nature in the towns, especially relaxation potentials of nature in an urbanized location. An identifying and growing the public assessment of the environment, this theory object to correcting the confirmed ways, in which nature could be depicted because that is the city to be harnessed, for the benefits of the human relaxation, wellbeing of the recommended method, in which environmental structures could be included into the urban design facilitation. The literature review behind the effects on the natural environment of human comfort and health effects of the public space, it is designed to combine the three focusing natures with sensory potentials, case study areas of the natural small public parks located in Batticaloa for the purpose of concluding recommendations of this dissertation. For example, it is expected that how these recommendations might be implemented and published in this situation existing in the Batticaloa Municipal Council area, in the neighbourhoods’ character of Kallady, Mugathuvaram and Dutch Bar, that increases density. The lessons have been discussed and planned to be transferred to the other urban areas that have become known areas of density to mix environment with the civic realm as these areas remain to be improved. This dissertation aims at pertaining to the foundation for thinking more censoriously and about the relationship related to the human nature in an urban area and how the common designing space could be used in a method of improving the relaxation and wellbeing of the people of the city surroundings
item: Conference-Full-text
Use of the concept of capillary barriers to optimize the support systems of deep vertical excavations in unsaturated soils
(IEEE, 2022-07) Ragavan, P; Rathnayaka, A; Kulathilaka, A; Rathnayake, M; Adhikariwatte, V; Hemachandra, K
In deep excavations, it is necessary to guarantee stability against catastrophic failure and to ensure that the deformations in the surrounding are within acceptable limits. Excavations done above the groundwater table can be supported with simple structures such as soldier pile walls. But the stability of the structure is affected by the infiltration of rainwater. If the infiltration of rainwater can be reduced the construction of a deep vertical excavation support system can be optimized. A Capillary Barrier (CB) which consists of a fine layer lying on top of a coarse layer at the ground level can cut off the infiltration into the lower layers. In this research study, initially, attempts were made to establish the critical parameters through parametric studies. A laboratory model of a Capillary Barrier was constructed with instrumentation and a rainfall pattern was applied. Experimental results were verified with GeoStudio, 2012 SEEP/W software and there was a very good agreement. A deep excavation supported by a soldier pile wall in an unsaturated soil was modelled thereafter with Midas GTS NX 3D software and the effectiveness of the capillary barrier in optimizing the design of the support system during a prolonged rainfall was illustrated.