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Analytical study on structural remaining life of airfield pavement using FWD
Published in Inge Hoff, Helge Mork, Rabbira Garba Saba, Eleventh International Conference on the Bearing Capacity of Roads, Railways and Airfields, Volume 3, 2022
F. Varela Soto, R. Pacheco-Torres
The traffic and pavement condition being known for the two study years, the data were entered in FAARFIELD to obtain the contribution of each aircraft to the damage caused, in this case, to the CDF rate. The service life of the pavement is estimated to be 30 years.
Final Engineering Design
Published in Connie Kelly Tang, Lei Zhang, Principles and Practices of Transportation Planning and Engineering, 2021
Pavement refers to material placed on top of local natural soil enabling smooth vehicle travel. The primary function of any pavement is to provide a long-lasting and smooth surface for vehicles to travel on under all weather conditions. A roadway surface must also provide adequate skid resistance enabling vehicles to stop safely. Over the years, additional pavement qualities such as quiet pavement minimizing tire noise, open drainage pavement facilitating stormwater runoff, and even solar electrical energy producing pavement have been researched and practiced.
The Development of a Permanent Deformation Design Model for Unbound Granular Materials with the Shakedown-Concept
Published in A. Gomes Correia, Fernando E.F. Branco, Bearing Capacity of Roads, Railways and Airfields, 2020
S. Werkmeister, R. Numrich, F. Wellner
Pavement design is a process intended to find the most economical combination of layer thickness and material type for the pavement, taking into account the properties of the soil foundation and the traffic to be carried during the service life of the road. Traditional design methods are more or less empirical in Germany but there is, world-wide, an increasing desire to develop analytical approaches. A prerequisite of a successful analytical method is the experimental measurement and appropriate mathematical characterisation of the permanent deformation behaviour of unbound granular materials (UGM). At the moment a model for the description and calculation of permanent behaviour is under development by the authors. Triaxial tests for the investigation of the permanent deformation behaviour are the basis of these studies.
Development of a temperature prediction model for asphalt pavements considering air temperature data of preceding hours
Published in International Journal of Pavement Engineering, 2022
Ashish Walia, Rajat Rastogi, Praveen Kumar, S. S. Jain
Pavement is a layered structure capable of withstanding the repetitive movement of wheel loads during its service life. However, the continuous application of (unanticipated) higher wheel loads on pavement structure may lead to its premature failure. The early deterioration may also happen due to harsh environmental conditions, improper drainage, and insufficient strength of the subgrade layer. Literature indicates that environmental factors like temperature and moisture content primarily affect pavement performance (Ali and Lopez 1996). Although a good design can substantially control the drainage effect, the temperature cannot be controlled through human intervention and thus needs to be addressed carefully. The temperature directly influences the characteristics and performance of the asphalt layer (topmost layer of the flexible pavement) in terms of its stress-absorbing behaviour or relative stiffness (Huang 2004). Therefore, determining pavement temperature in the Asphalt Concrete (AC) layer is important for its performance assessment. Performance assessment can be done through either destructive or non-destructive testing (NDT). The destructive testing includes the extraction of cores, whereas the NDT technique facilitates assessment without much affecting the structural integrity of the pavement. The NDT-based structural evaluation may be carried out using Benkelman Beam or Falling Weight Deflectometer (FWD) equipment.
Optimal pavement management strategy development with a stochastic model and its practical application to Ugandan national roads
Published in International Journal of Pavement Engineering, 2022
Felix Obunguta, Kakuya Matsushima
A pavement structure will deteriorate over time due to usage (traffic loads) and environmental agents (e.g. temperature and moisture). Considering the discrete time axis and that pavements are regularly inspected after specified discrete intervals , number of road inspections are carried out as defined by the discrete time axis as . At a given inspection time , road inspectors observe pavement condition . Actions are performed on pavements in correspondence to observed condition after inspection. Once action is taken, pavement condition is assumed to improve to a better condition . This improvement in pavement condition can be expressed using , the better condition of a pavement section following repair (Equation (1)):
Modelling the response of large-size subbase materials tested under varying moisture conditions in a heavy vehicle simulator
Published in Road Materials and Pavement Design, 2022
Marit Fladvad, Sigurdur Erlingsson
Environmental conditions are important inputs to pavement design, combined with traffic load, material choice and layer thicknesses. Climate changes are in many areas expected to lead to increased precipitation and more intense rainfall events (Seneviratne et al., 2012). Such changes will lead to increased moisture within road structures and possible overloading of road drainage systems. Pavement design has traditionally been done using empirical methods, based on long-term experience with similar materials and conditions (ARA Inc., 2004). When climate changes cause a shift towards increased moisture levels, empirical methods can no longer be used to predict pavement performance. A transition from empirical to mechanistic design is needed, and to achieve this, we need to be able to model the behaviour of the pavement structures under all conditions (Erlingsson, 2007; Mamlouk, 2006).