Browsing by Author "Gunatilake, MMDV"

Now showing 1 - 7 of 7

item: Conference-Full-text
Development of a finite element model for concrete block paving
Gunatilake, MMDV; Mampearachchi, WK
Concrete Block Paving (CBP), which is a predominant construction method used nowadays, is based on the ancient road construction technology “Stone Paving”. The use of CBP is a common sight in most of the developing countries due to its economic adaptability. Although it has emerged as a costeffective paving material, it is yet being developed as a full-fledged construction technique. The aim of this research was to develop a finite element model for CBP and evaluate the deflections in pavement with the application of loads. A three-dimensional finite element model was built to measure the elastic deflection basin with ANSYS finite element modelling software. The reason for developing a finite element model is, as the construction of concrete block pavements for experimenting is costly and challenging, a finite element model simulating the field conditions could be used to overcome these issues and perform further research. Previously developed finite element models and laboratory models were studied. The results obtained from the developed finite element model were verified with the deflection values obtained in a laboratory scaled model. Similar deflection basins could be observed for different load cases. Further studies on the finite element model could be carried out to observe the effect on the deflection of a concrete block pavement with respect to the variation of the block shape.
item: Conference-Full-text
Effect of the Activities Inside a Hospital Theatre of its IAQ
(2016-05-26) Gunaratne, WDSP; Gunatilake, MMDV; Jayasinghe, C; Madushanka, HKR; Perera, TM; Perera, SAS; Rajapaksa, S
A close relationship can be observed between the building performance and the activities associated with the building. Since those activities have a great impact on Indoor Air Quality (IAQ) of the building, it is necessary to consider the activities that would take place inside a building, at its design stage. In this research study, the effect of the activities associated with a hospital theatre, on its IAQ has been studied since the theatre staff of a leading hospital in Sri Lanka, experience some discomfort while being inside the theatre. In order to evaluate this, variation of Carbon Dioxide (CO2), Carbon Monoxide (CO), Total Volatile Organic Compounds (TVOC) and Particulate Matter less than 2.5 microns (PM2.5) concentrations inside the theatre were measured and analysed. Significant variations were observed in the concentrations of CO2, TVOC and CO inside the operation theatre. CO2 concentration inside the room increased at the beginning and end of the surgeries due to high occupant density and also during Laparoscopic surgeries. TVOC concentration was affected by the usage of different chemicals during the surgery. Major effect to the CO concentration was by Diathermy.
item: Thesis-Abstract
Finite element model approach to determine the optimum dimensions for interlocking concrete blocks used for road paving
(2015-09-17) Gunatilake, MMDV; Mampearachchi, WK
Concrete Block Paving (CBP), which is a predominant construction method used nowadays, is based on the ancient road construction technology “Stone Paving”. The use of CBP is a common sight in most of the developing countries due to its economic adaptability. Although it has emerged as a cost-effective paving material, it is yet being developed as a full-fledged construction technique. The aim of this research was to determine optimum dimensions for concrete blocks using a finite element model, evaluating the deflections and stresses in pavement with the application of loads. A three-dimensional finite element model was built to measure the elastic deflection basin with ANSYS finite element modelling software. The reason for developing a finite element model is, as the construction of concrete block pavements for experimenting is costly and challenging, a finite element model simulating the field conditions could be used to overcome these issues and perform further research. Previously developed finite element models and laboratory models were studied. The results obtained from the developed finite element model were verified with the deflection values obtained in a laboratory scaled model. Similar deflection basins could be observed for different load cases. Several block types were considered initially and block dimensions with best performance were identified. Based on those results a new block type which optimizes the performance was proposed carrying out finite element analysis. An alternate block type to the proposed block type was also analysed and it could only be recommended for non-traffic areas. In addition, the effects of wheel path on concrete block pavement in both longitudinal and transverse directions were considered to have an idea about the variation of stress and deflection at different locations of the pavement. Although no significant values were observed with the block orientation, closer the wheel path to the edges higher the stresses obtained.
item: Conference-Full-text
Measurement and analysis of indoor air pollutants in a room sprayed with a locally manufactured air freshener
(2013-11-13) Perera, SAS; Jayasinghe, C; Gunaratne, WDSP; Gunatilake, MMDV; Madushanka, HKR; Perera, TM
In the modern world, since, people like to live, work and travel in, aesthetically pleasing, comfortable environments with pleasant odour, they tend to use, decorative interiors, air conditioners and air fresheners, whereas, during good old days, natural alternatives, such as, natural ventilation, natural fragrances and natural interiors were used to make living comfortable. Today, in most of the indoor environments, air fresheners are sprayed, to give a pleasant odour. This is practiced in most commercial buildings, factories, houses, as well as, cars and other modes of transport. However, many studies conducted by researchers, internationally, have. revealed that many chemicals are used in the manufacture of air fresheners, some of which, might have adverse impacts on human health. The main objective of this research project was to measure and analyse concentrations of Carbon Dioxide (CO2), Carbon Monoxide (CO), Total Volatile Organic Compounds (TVOC) and Particulate Matter less than 2.5 microns (PM2.5), due to the spray of air freshener into an air conditioned office room, with no external air circulation. To make the research relevant to Sri Lanka, a locally manufactured, popular brand of air freshener packed in a non pressurised finger operated spray bottle, was used to spray air freshener into the room. The results have revealed that, the indoor air TVOC levels can significantly rise beyond permissible limits, in an air conditioned room, with no external air circulation.
item: Conference-Abstract
Measurement and analysis of indoor air pollutants in a room sprayed with a locally manufactured airfreshener
(2016-08-10) Perera, SAS; Jayasinghe, C; Gunaratne, WDSP; Gunatilake, MMDV; Madushanka, HKR; Perera, TM
In the modern world, since, people like to live, work and travel in, aesthetically pleasing, comfortable environments with pleasant odour, they tend to use, decorative interiors, air conditioners and air fresheners, whereas, during good old days, natural alternatives, such as, natural ventilation, natural fragrances and natural interiors were used to make living comfortable. Today, in most of the indoor environments, air fresheners are prayed, to give a pleasant odour. This is practiced in most commercial buildings, factories, houses, as well as, cars and other modes of transport. However, many studies conducted by researchers, internationally, have. revealed that many chemicals are used in the manufacture of air fresheners, some of which, might have adverse impacts on human health. The main objective of this research project was to measure and analyse concentrations of Carbon Dioxide (CO2), Carbon Monoxide (CO), Total Volatile Organic Compounds (TVOC) and Particulate Matter less than 2.5 microns (PM2.5), due to the spray of air freshener into an air conditioned office room, with no external air circulation. To make the research relevant to Sri Lanka, a locally manufactured, popular brand of air freshener packed in a non pressurised finger operated spray bottle, was used to spray air freshener into the room. The results have revealed that, the indoor air TVOC levels can significantly rise beyond permissible limits, in an air conditioned room, with no external air circulation.
item: Article-Full-text
A Sustainable Road Construction Material for Low Volume Roads
(Faculty of Architecture University of Moratuwa, 2013) Mampearachchi, WK; Gunatilake, MMDV
The need of spending highway investments more efficiently is greater than ever before, due to escalation of prices of the conventional paving materials (asphalt, concrete). Hence, the road designers are in the verge of using alternative materials for the road construction which brings sustainable living conditions. Thus, focus has been on “Concrete Block Paving (CBP)”, a road construction methodology which is based on ancient road construction technology “Stone Paving”. In general, the applications of CBP are categorized according to the traffic condition as non-traffic, light traffic, medium traffic and heavy & very heavy traffic. The results of the study indicate that the life cycle cost of CBP is lower than the other paving materials although the initial construction cost is slightly high. When the performance of the three types of paving materials are evaluated,\ in addition to the low life cycle cost, the ability of accommodating and maintaining utility services, thermal comfort, aesthetic appearance and environmentally friendly behaviour can be highlighted as the key advantages of CBP
item: Article-Full-text
A sustainable road construction material for low volume roads
(2014-04-09) Mampearachchi, WK; Gunatilake, MMDV
The need of spending highlllq)linvestments more efficientlY is greater than ever before, due to escalation of prices of the conventional paving materials (asphalt, concrete).Hence, the road designers are in the verg,eof using alternative materials for the road construction iuhich brings sustainable living conditions. Thus, focus has been on "Concrete Block Paving (CBP)", a road construction methodology lvhich is based on ancient road construction technology '3'tone Paving". In general, the applications of CBP are categorized according to the traffic condition as non-traffic, light traffic, medium traffic and hea1!Y& very hea1!Ytraffic. The results of the stu4J indicate that the life rycfe cost of CBP is lower than the other paving materials although the initial construction cost is slightlY high. When the peiformance of the three types ofpaving materials are evaluated, in addition to the 10111 life rycfe cost, the ability of accommodating and maintaining utility services, thermal comfort, aesthetic appearance and environmentallYfriendlY behaviour can be highlighted as the kry advantages of CBP.