Browsing by Author "Ong, GP"

Now showing 1 - 3 of 3

item: Article-Full-text
Analytical evaluation of aircraft operational risks from runway rutting
(Taylor & Francis, 2016) Pasindu, HR; Fwa, TF; Ong, GP
Runway surface distortions such as rutting allow water to accumulate on the runway surface which may cause aircraft operational risks related to hydroplaning and loss of friction. This may increase the runway excursion risk during wet weather conditions. Several standards relating to airfield pavement maintenance have documented that rutting can cause safety hazards to aircrafts due to hydroplaning risk. This paper proposes an analytical approach to evaluate the hydroplaning potential for aircrafts due to the flooded ruts of a runway pavement and evaluate the operational risk. A finite element model is developed to simulate aircraft tyre hydroplaning under given set of operating conditions. By performing this evaluation for different rut depths, an assessment of the relative severity levels of different rut depths with respect to hydroplaning can be made. A numerical example is presented to illustrate the application of the procedure to evaluate operational risks to aircraft from runway rutting.
item: Conference-Full-text
Laboratory characterization of cement-treated rock rubble as airfield pavement base layer
(Springer, 2021) Tan, JH; Khan, Q; Yannick, CHN; Ong, GP; Pasindu, HR; Bandara, S; Mampearachchi, WK; Fwa, TF
As a means to ensure economic and environmental sustainability in pavementworks, the use of locally obtainedwastematerials (rocks) in base layer design as well as exploring energy-efficient construction methods is highly encouraged. This study explores the use of cement-treated recycled rocks of up to 1.5 in. (37 mm) in size as an alternative base layer material for the construction of airfield pavements. The Preplaced Aggregate Concreting Method (PAC) was implemented to construct the base layer without any vibration or compaction effort. This is an unconventional airfield pavement base construction method, which solely relies on the flowability of the grout mix to ensure the voids between rocks are filled up bymeans of gravity. The experimental program explores the compressive strength, modulus of elasticity and tensile strength of the material. The preliminary results demonstrate the potential of CTRR as a viable base layer alternative to existing stabilized bases.
item: Conference-Full-text
Selection of image processing algorithms for evaluation of pervious pavement pore network properties
(Springer, 2021) Jagadeesh, A; Ong, GP; Su, YM; Pasindu, HR; Bandara, S; Mampearachchi, WK; Fwa, TF
Digital Image Processing (DIP) algorithms are often required as a precursor tomeasure the internal characteristics of pavement structures during X-ray computed tomography (XRCT) based non-destructive evaluation (NDE) of pavement materials. The improper use of DIP algorithms can result in the significant underor over-estimation of internal pavement characteristics, thereby affecting pavement design and maintenance strategies. Past research studies highlighted the significance of threshold segmentation algorithms and binarization of greyscale images on the porosity and permeability characteristics of pervious pavement mixtures. In addition, the use of a watershed segmentation algorithm was introduced to separate interconnected pore network structure into multiple pores. However, isolated pores were not removed in past analyses found in the literature due to a lack of consideration in using ungrouping algorithm to segregate connected and isolated pores. The main objective of this study is to select the appropriate DIP algorithms that can be used to evaluate pervious pavement pore network properties from three-dimensional XRCT based images. In this paper, a key microstructural pore parameter was investigated using various DIP algorithms for different pervious pavement mixtures and recommendations are made. It is expected that the results presented in this paper can help researchers understand the importance of DIP algorithms on XRCT-based pavement evaluation studies.