Analysis of Dynamic Deviator Stress of Reinfored Subgrade under Traffic Loading

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.178-181.1392 ◽

2012 ◽

Vol 178-181 ◽

pp. 1392-1395

Author(s):

Shi Chuan Wang

Keyword(s):

Shear Stress ◽

Stress Distribution ◽

Compressive Stress ◽

Asphalt Concrete ◽

Residual Deformation ◽

Concrete Pavement ◽

Key Factors ◽

Traffic Loading ◽

Deviator Stress ◽

Asphalt Concrete Pavement

In order to study the influence of reinforcement on the distribution of dynamic deviator stress along the depth of subgrade, reinforced and unreinforced subgrade of graded-broken-stone-based asphalt concrete pavement under traffic loading was modeled by implicit dynamic FEM. Analytical results show that reinforcement can improve the vertical compressive stress distribution, and decrease shear stress transmitted to the surface of subgrade. The deviator stress on the upper part of reinforced subgrade is reduced distinctly, which is one of the key factors that can cause residual deformation. Therefore, reinforcement can restrain the development of residual deformation of subgrade induced by traffic loading.

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Reserving the Sustainability of Flexible Pavement In Terms Of Microcrack Healing

10.24086/aces2020/paper.195 ◽

2021 ◽

Author(s):

Saad Sarsam ◽

Keyword(s):

Fatigue Life ◽

Asphalt Concrete ◽

Concrete Pavement ◽

Asphalt Mixtures ◽

Asphalt Binders ◽

Actual Behavior ◽

Self Healing ◽

Traffic Loading ◽

Asphalt Cement ◽

Asphalt Concrete Pavement

The fatigue life of Asphalt concrete pavement consists of two components, namely the resistance to fracture and crack, and the ability to heal the micro cracks. Both processes changes with temperature and time. Such processes exhibit the sustainability potential of asphalt concrete pavement. Repeated traffic loading and environmental impact causes deterioration in asphalt concrete pavement mixes and exhibit micro cracking and decreases its stiffness. However, due to the crack healing phenomena effect, asphalt mixes can demonstrate strength recovery and prolongs the fatigue life of asphalt mixtures. Many studies have been conducted to characterize the asphalt healing and its mechanisms. The approach to study this potential requires implementation of proper additives to the asphalt cement which can improve the self healing property of asphalt concrete and reserve the quality of the pavement. The aim of this work is to thoroughly understand the cracking and healing mechanisms and to define appropriate laboratory tests and type of additives which can increase the healing potential and can be used for a reliable performance-related selection and characterization of the asphalt binders, and the suitable asphalt concrete mixture based on the traffic loading and the environment issues. It was felt that it is essential to evaluate whether it is possible to achieve accelerated healing in asphalt mixtures within laboratory conditions, which could represent the actual behavior in the field. It was concluded that the process of healing is a sustainable measure and can be used to balance the damage process. The influence of several additives on the microcrack healing concept was discussed. The amount and rate of healing of asphalt cement which depend on several properties such as; its healing potential, stiffness, and surface free energy was also analized.

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Analysis on the Traffic-Response of Asphalt Concrete Overlay on PCC-Slab

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.178-181.1623 ◽

2012 ◽

Vol 178-181 ◽

pp. 1623-1627

Author(s):

Wei Xu ◽

Xuan Cang Wang ◽

Shan Qiang Li

Keyword(s):

Finite Element ◽

Asphalt Concrete ◽

Element Model ◽

Concrete Pavement ◽

Comprehensive Model ◽

Reflective Cracking ◽

Traffic Loading ◽

Asphalt Overlay ◽

Pavement Construction ◽

Asphalt Concrete Pavement

Focusing on the severity of asphalt concrete pavement crack, the optimization analyzing finite element model(FEM) of typical asphalt overlay pavement was developed to address reflective cracking, in which the analysis of traffic-loading response were concentrated on the stress-intensive areas close to the joints or cracks. The FE sensitive analysis, evaluating the influence of pavement construction parameters, including modulus and thickness of pavement courses, is useful to establish comprehensive model of overlay pavement construction.

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Load Spectra–Incorporated Fatigue Cracking Model Implementation and Case Study

Transportation Research Record Journal of the Transportation Research Board ◽

10.3141/2640-01 ◽

2017 ◽

Vol 2640 (1) ◽

pp. 1-10

Author(s):

Sheng Hu ◽

Fujie Zhou ◽

Tom Scullion

Keyword(s):

Asphalt Concrete ◽

Fatigue Cracking ◽

Pavement Design ◽

Design System ◽

Key Factors ◽

Spectra Analysis ◽

Traffic Loading ◽

Load Spectra ◽

Comparison Results ◽

Asphalt Concrete Pavement

Traffic loading is one of the key factors that may cause asphalt concrete pavement fatigue cracking. Axle load spectra input provides an opportunity for evaluating the pavement response under real traffic loads throughout the pavement design life. This paper describes the methodology of incorporating axle load spectra into the mechanistic–empirical fatigue cracking model that uses a fracture mechanics method to determine crack propagation. The paper also presents the incorporation of the method into the Texas mechanistic–empirical flexible pavement design system. Several load spectra cases were studied, and the percentages of the corresponding fatigue cracking areas were predicted and compared. The comparison results confirmed the necessity of load spectra analysis. Overall, the implemented load spectra–incorporated asphalt concrete fatigue cracking model generated rational results. Further research is continuing on field validation and calibration.

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