Research Papers - Department of Civil Engineering

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    PublicationEmbargo
    Identification of the Impact on Road Roughness on Speed Patterns for Different Roadway Segments
    (IEEE, 2020-07-28) Abeygunawardhana, C; Sandamal, R. M. K; Pasindu, H. R
    Pavement surface condition is one of the factors that affect driver comfort, operation speed, service volume, and traffic safety. Even though several studies have conducted recently to find the effect of different roadway characteristics on traffic stream performance, not many were focused on the impact of road roughness on operating speeds. Therefore, this research will investigate the impact on road roughness on speed patterns for different roadway segments under different flow levels. The unevenness of a road is measured as road roughness and it has been globally accepted as a metric to evaluate the pavement condition and it relates to the conditions perceived by the road users. In addition to the user discomfort, rough roads would result in, speed reduction and an increase in vehicle operating costs. International Roughness Index (IRI) measured by smartphone application is used as the indicator for road roughness in this study. The effect of road roughness is investigated at Free Flow Speed (85 th percentile speed) and 50 th percentile speed which is determined using the speed distributions that occurred during specific time intervals. Further, the abovementioned behavior is analyzed separately for junctions, mid-block sections, and horizontal curves to represent different roadway conditions.
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    PublicationOpen Access
    Impact of change in head and neck position on ultrasound localisation of the cricothyroid membrane: an observational study
    (http://www.anaesthesiacorrespondence.com, 2019-01) Dixit, A; Ramaswamy, K. K; Perera, S. V. T; Sukumar, V; Frerk, C
    The ideal position for performing surgical cricothyroidotomy is with full neck extension. Some authors have recommended marking the cricothyroid membrane before general anaesthesia, typically with the patient's head and neck in a neutral position. The primary aim of this observational study was to determine whether skin marks made over the centre of the cricothyroid membrane with the head and neck in the neutral position moved outside the boundaries of the membrane when the neck was subsequently extended. The secondary aim was to assess changes in the height of the cricothyroid membrane between the neutral and extended positions. Twenty-two volunteers completed the study. With the head and neck in the neutral position, the distance between the upper and lower borders (‘height’) of the cricothyroid membrane was measured by a radiologist using ultrasound. The skin was marked over the mid-point of the membrane. The subject then maximally extended the neck, and the measurements and marking were repeated. The skin marking over the centre point of the cricothyroid membrane moved by median (IQR [range]) 5 (4–6 [0–10]) mm when the head and neck were moved from a neutral to a fully extended position. The initial skin mark moved to lie outside the boundary of the cricothyroid membrane in 12 of 22 subjects after extending the neck. The height of the cricothyroid membrane increased by 30% with the neck extended. We recommend that marking the skin in preparation for cricothyroidotomy should be performed with the neck extended, not with the head and neck in the neutral position as previously suggested.
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    PublicationOpen Access
    Impact of urbanization on earth resources in suburbs of Colombo, Sri Lanka
    (NSF: Colombo, 2019) Rathnayake, U. S
    Climate change is believed to be a critical issue and there is enough evidence to identify the impact of climate change. Sri Lanka is expected to be one of the most affected countries from adverse impact of climate change. Various climatic models propose a rise of rainfall intensity to south Asian region while the number of rainy days are to be reduced. Therefore, the necessity is raised to find the clear trends in climatic factors in the region. However, a very few research work was carried out to see the climatic changes over the last few decades in Sri Lanka. Temporal variation of precipitation (rainfall) can be a good indicator to identify the trends in climate. In addition, these rainfall variations are used in many engineering aspects, including design of massive civil engineering structures like dams, design of water supply networks, etc. Furthermore, the rainfall variations are not only important in engineering aspects but also heavily in agriculture. Therefore, this research work targets to find the temporal variations of rainfall n Sri Lanka and then, to project the results to the available water resources.