scholarly journals Parameter Optimization of Graded Macadam Transitional Layer for Inverted Asphalt Pavement Based on the Mechanical Response and Strength Standard

2021 ◽  
Vol 2021 ◽  
pp. 1-11
Author(s):  
Chen Zhang ◽  
Yong Lei
Keyword(s):  
Shear Stress ◽  
Surface Layer ◽  
Tensile Stress ◽  
Parameter Optimization ◽  
Mechanical Response ◽  
Asphalt Pavement ◽  
Maximum Shear Stress ◽  
Base Layer ◽  
Transitional Layer ◽  
Cold Regions

To improve the durability of asphalt pavement with heavy traffic conditions in cold regions, the parameter optimization of graded macadam transitional layer (GMTL) for the inverted asphalt pavement based on the mechanical response and the strength standard was studied. The stress distribution laws of GMTL were studied with different loads by means of BISAR3.0. The influences of the thickness and the modulus of GMTL on the pavement stress were analyzed. The optimal thickness and the modulus range of the GMTL were determined. Combined with a self-developing real-time data acquisition and a processing system for aggregate attitude (RDAPS), the strength control standard of the GMTL was established. Finally, the performance of the optimized inverted asphalt pavement structure was verified through the MEPDG design method. The results show that the tensile stress at the bottom of the surface layer reduced by about 58%, and the shear stress in GMTL increased by about 17% when the modulus of GMTL increases from 300 MPa to 800 MPa. However, the change in modulus has no significant influence on the maximum shear stress in the asphalt surface layer and the tensile stress in the base layer bottom. When the thickness of GMTL increases from 12 cm to 20 cm, the tensile stress in the bottom of the base layer reduced by about 31%. Based on the mechanical results from simulation calculation and the technical indicator required in the field, the recommended optimal parameters of GMTL are the modulus of 700 MPa and the thickness of 18 cm. In addition, the spatial attitude angle ΦN of wireless intelligent attitude aggregate (WIAA), the compressive strength Rc standard, and the California Bearing Ratio (CBR) standard were analyzed, and the strength control standard of inverted asphalt pavement with GMTL was proposed, namely, CBR ≥ 354%, Rc ≥ 1.06 MPa, and ΦN ≤ 3°. A significant improvement in the resistance to crack can be seen in the inverted asphalt pavement when the optimized structure was applied. Taking the 20-year service life as an example, the top-down cracks reduced by 29.3% and the bottom-up cracks reduced by 32.6% in comparison to the original structure. The recommended structural parameters of GMTL could be used to guide the construction and design of inverted asphalt pavement in cold regions.

The Mechanical Response Analysis of the Airport Asphalt Pavement Considering Horizontal Load

2013 ◽  
Vol 645 ◽  
pp. 471-475
Author(s):  
Jian Jiao ◽  
Shu Dong Meng ◽  
Qiang Jiao ◽  
Nan Li
Keyword(s):  
Shear Stress ◽  
Surface Layer ◽  
Tensile Stress ◽  
Large Scale ◽  
Mechanical Response ◽  
Asphalt Pavement ◽  
Response Analysis ◽  
Horizontal Load ◽  
Horizontal Shear ◽  
Finite Element Software

In order to research the mechanical response of asphalt pavement under horizontal load which produced by the large aircraft braking process, large-scale finite element software is used in this paper. The model of main landing gear load is established to analyze the change of principal mechanics indexes of airfield pavement when the aircraft has different landing distance. The results show that: the horizontal load has a significant influence on the normal stress of landing direction, but the influence area is concentrated in the rear of the wheel. The horizontal load has more effect on horizontal shear stress and longitudinal shear stress, while has less effect on tensile stress of surface layer bottom, tensile tress of base course bottom and transverse shear stress. The tensile stress of surface layer will increase significantly when the braking distance is less than 2000m. Meanwhile, thickening surface layer could decrease the tensile stress and increase the fatigue lifetime apparently.

Analysis of Performance Decay Behavior for Asphalt Pavement Based on Aging

2013 ◽  
Vol 723 ◽  
pp. 22-26 ◽  
Author(s):  
Pei Long Li ◽  
Zhan Ding ◽  
Zheng Qi Zhang
Keyword(s):  
Shear Stress ◽  
Service Life ◽  
Tensile Stress ◽  
Simulation Analysis ◽  
Asphalt Pavement ◽  
Maximum Shear Stress ◽  
Maximum Tensile Stress ◽  
Pavement Structure ◽  
Analysis Of Performance ◽  
Decay Behavior

Aging is a main factor affecting the durability of asphalt pavement. To study decay behavior of asphalt pavement with aging, aged asphalt was extracted from stratified pavement mixtures for different service-life. The changes of asphalt properties with service time and depth variations of the pavement were discussed. And numerical simulation analysis of pavement structure was conducted with pavement gradient modulus changes caused by aging. The results indicate that asphalt stiffness increases and low-temperature performance decays sharply with the extension of pavement service life, especially in the first several years. The vertical aging differences from top to bottom of pavement were significant, the aging extents decrease continuously from the surface, which cause the gradient changes of pavement modulus. The maximum tensile stress and maximum shear stress all increase with surface modulus increasing, so more serious aging can induce greater gradient modulus, shear stress and tensile stress are larger under the same loads, which have more serious damage to the pavement structure.

Dynamic Response of Asphalt Pavement on Semi-Rigid Base due to Heavy Load

2013 ◽  
Vol 405-408 ◽  
pp. 1745-1752
Author(s):  
Li Juan Zhang
Keyword(s):  
Shear Stress ◽  
Surface Layer ◽  
Tensile Stress ◽  
Compressive Stress ◽  
Asphalt Pavement ◽  
Road Surface ◽  
Rigid Base ◽  
Heavy Load ◽  
Vertical Strain ◽  
Surface Deflection

The purpose of this paper is to study dynamic-characteristics of asphalt-pavement on semi-rigid base loaded with moving, heavy-load. Based on transient-dynamics theory, three-dimensional finite-element (FE) model was developed for structural dynamic-responses analysis using ANSYS software. The heavy-duty axle-load model was established according to Belgium-Design Code, and the dynamic-load was simplified as sinusoidal-wave load. For the pavement mechanics indexes (road-surface deflection, the vertical and lateral stress, the shear stress and the strain), the time-history curves and distribution conditions in the structure were presented. Expect tensile-strain at surface-layer, the relationship between axle-load weight and mechanic-indexes are almost linearly proportional. The calculation shows that under moving heavy-load, the surface-layer suffers from rather high vertical compressive-stress and shear-stress, the base and subbase are loaded with high tensile-stress and the subgrade top undergoes large vertical-strain . For asphalt-pavement on semi-rigid loaded with moving, heavy-load, besides the conventional indexes (including road-surface deflection and tensile-stress at the bottom of base or subbase), the design indexes should also include the shear-stress on road surface, the vertical-strain on the top of subgrade and the vertical compressive-stress on road surface.

Influence Analysis of Crack Depth and Position on Asphalt Pavement Structure with 3D Finite Element

2012 ◽  
Vol 450-451 ◽  
pp. 267-272 ◽  
Author(s):  
Peng Wang ◽  
Can Cui
Keyword(s):  
Finite Element ◽  
Shear Stress ◽  
Shear Strength ◽  
Surface Layer ◽  
Tensile Stress ◽  
Asphalt Pavement ◽  
Top Down ◽  
Eccentric Load ◽  
3D Finite Element ◽  
Pavement Structure

In recent years the research on Surface-initiated longitudinal cracking along wheelpath (or Top-Down cracking) is become a fresh hotspot in the field of pavement damage focused by international asphalt pavement engineering.Because the traditional load is the vertical surface load with uniform tire pressure, this loading is applied at only one position and no effort is made to distinguish between tire pattern.The traditional method can’t explain the mechanism of the top-down cracking. In order to discuss the mechanism of TDC, this paper establish a 3D finite element model of semi-rigid pavement structure and use the large finite element software Abaqus. The analysis shows that, in the crack beginning stage, the main tensile stress appears under the center of the load on the sub-base of the pavement,and its value increases with the time. When cracks appear in the base, the position of the main tensile stress appears at the bottom of the surface layer, under the outside edge of wheel path. The value of the main shear stress increases at the stage of the cracks beginning, but the increase is small. The value of the main shear stress decreases when the cracks appear in the middle of the surface layer, and the position of the main shear stress changes with the depth of the cracks. With the increase of the cracks’ depth, the adverse influence of the shear stress becomes weaker and weaker.So the key of controlling the cracks in the surface layer is prevention. To prevent the development of the cracks, the tensile strength of the layer’s material should be enhanced in any way. The stress and its value resulted from the vehicle loaded on the structure layer is bigger than the other cases when the position of the cracks is at the edge of wheel path, and the stress is much bigger than the shear strength and the fracture toughness of the material of the layer. As the shear strength of the material is not enough, the vertical cracks are easier to appear at the edge of wheel path under the load of the vertical. Once it appearing, the cracks will extended into the layer because of the load of vertical. Eccentric load generates greater stress in the structure than the load loaded upright. In fact, though, non-channeling can reduce the appearance of the tracks, eccentric load enhance the development of the cracks in the surface because of the existence of the cracks in the surface layer.

Mechanical Response of Longitudinal Slope Segments Based on Burgers Model

2011 ◽  
Vol 243-249 ◽  
pp. 4172-4177
Author(s):  
Bao Chen ◽  
Xuan Cang Wang ◽  
Ke Mu
Keyword(s):  
Finite Element ◽  
Shear Stress ◽  
Mechanical Response ◽  
Asphalt Pavement ◽  
Maximum Shear Stress ◽  
Longitudinal Gradient ◽  
Load Bearing ◽  
Burgers Model ◽  
Longitudinal Slope ◽  
Stress Behaviors

Asphalt Pavement was damaged more seriously in longitudinal Gradient than common segment because of its special load bearing conditions. This paper establishes a 3D Visco-elasto-plastic Finite Element to analyses the stress respond of pavement structure, calculating the discipline of stress behaviors under different gradient. Burgers model was used to study the factors which can influence on tracking, for example longitudinal Gradient, speeds and frequency of axle load. Result of calculation show that the maximum shear stress grows as the gradient increases. Rutting of pavement was small before a certain number of axle loads, but when beyond the certain number, the rutting incense notably, and the slower speed the vehicle has, the deeper tracking the pavement responds.

scholarly journals Analysis of Loading Stress of Pavement Structure using One-Step Forming Cement-Stabilized Macadam Base

2019 ◽  
Vol 136 ◽  
pp. 04042
Author(s):  
Yue Qin ◽  
Yongjun Meng ◽  
Zubiao Lu ◽  
Qixiong Zhao ◽  
Hongliu Rong
Keyword(s):  
Surface Layer ◽  
Working Conditions ◽  
Maximum Shear Stress ◽  
Thin Layers ◽  
Base Layer ◽  
Pavement Performance ◽  
Principal Stresses ◽  
Large Thickness ◽  
One Step ◽  
Pavement Structure

Layered construction of large thickness cement-stabilized macadam base makes the base change from designed being forced by whole layer to being forced by two thin layers, the existence of interfacial friction between two thin layers reduces the pavement performance of the base, which finally cause the reduction of pavement performance of whole pavement structure. To analyze the load responses of large thickness cement-stabilized macadam base asphalt pavement under different working conditions, pavement surface deflection, maximum principal stresses of surface layer bottom and base layer bottom, minimum principal strain of soil base top and maximum shear stress of surface layer bottom under two different working conditions(layered construction and one-step forming) are taken as indexes and are obtained by finite element analysis method in this paper.

Mechanism Analysis of Rutting at Urban Intersections Based on Numerical Simulation of Moving Loads

2010 ◽  
Vol 152-153 ◽  
pp. 1192-1198 ◽  
Author(s):  
Ze Jiao Dong ◽  
Zong Jie Sun ◽  
Xiang Bing Gong ◽  
Hao Liu
Keyword(s):  
Finite Element ◽  
Shear Stress ◽  
Asphalt Pavement ◽  
Moving Load ◽  
Maximum Shear Stress ◽  
Uniform Motion ◽  
Dynamic Mode ◽  
Mechanism Analysis ◽  
Horizontal Shear ◽  
Pavement Structure

Frequent starting and braking of vehicles causes rutting of asphalt pavement at urban intersection. As a result, dynamic response of pavement subjected to these kinds of vehicle loadings can be used to analyze rutting mechanism. At first, vehicle loading at urban intersection was described by a vertical and horizontal combined moving pressure with variable speeds. Then, three-dimensional finite element model in transient dynamic mode is developed based on the practical pavement structure. And the moving load, boundary conditions and material parameters were briefly introduced. Finally, through the comparison of time histories and spatial distribution among accelerating, decelerating and uniform motion, mechanism of rutting of asphalt pavement at urban intersections was illustrated according to the finite element simulation. It shows that frequent starting and braking of vehicle at urban intersections, obviously change the stress distribution within pavement structure compared with uniform motion case. The distribution and amplitude of maximum shear stress and horizontal shear stress was observed during the passage of the loading, which will result in shear flow deformation. Pavement structure subjected to moving load exhibits an alternative characteristic which will accelerate the rutting damage of pavement.

Mechanical Response of Asphalt Pavement under Overloading

2013 ◽  
Vol 361-363 ◽  
pp. 1869-1872 ◽  
Author(s):  
Sheng Jie Liu ◽  
Qing Long You
Keyword(s):  
Tensile Stress ◽  
Mechanical Response ◽  
Asphalt Pavement ◽  
Compressive Strain ◽  
Flexible Pavement ◽  
Load Application ◽  
Rigid Base ◽  
Linear Elastic ◽  
Application Procedure ◽  
Surface Increase

This paper examines theoretically the possible mechanical response changes on both bituminous pavement structure using linear elastic method, the change regulation of deflection,stress on the bottom of base and subbase and compress strain on the top of subgrades between semi-rigid base and flexible pavement pavement. In the load application procedure, a dual wheel with the a series of pressure was chosen.The results have shown that the deflection tensile stress and subgrade compressive strain on the surface increase with the increase of axle load and they would result in serious effect of overloading on the earlier damage of asphalt pavement.

scholarly journals ON THE MECHANICAL RESPONSE OF A PRESSURIZED FUNCTIONALLY-GRADED CYLINDER

2014 ◽  
Vol 5 (1) ◽  
Author(s):  
Vlado Lubarda
Keyword(s):  
Shear Stress ◽  
Power Law ◽  
Functionally Graded Material ◽  
Elastic Moduli ◽  
Mechanical Response ◽  
Maximum Shear Stress ◽  
Radial Distance ◽  
Functionally Graded ◽  
Graded Material ◽  
Radial Inhomogeneity

A pressurized functionally-graded cylinder is considered made of the material whose elastic moduli vary with the radial distance according to the power-law relation. Some peculiar features of the mechanical response are noted for an incompressible functionally-graded material with the power of radial inhomogeneity equal to two. In particular, it is shown that the maximum shear stress is constant throughout the cylinder, while the displacement changes proportional to 1/r along the radial distance. No displacement takes place at all under equal pressures applied at both boundaries.

Analysis of Waterproof Bonding Layer in Permeable Asphalt Pavement

2012 ◽  
Vol 268-270 ◽  
pp. 660-663
Author(s):  
Xiao Ge Tian ◽  
Ying Liu
Keyword(s):  
Shear Stress ◽  
Tensile Stress ◽  
Asphalt Pavement ◽  
Interfacial Shear Stress ◽  
Interfacial Shear ◽  
Interfacial Stress ◽  
Bonding Layer ◽  
Maximal Tensile Stress ◽  
Tensile Zone

Waterproof bonding layer is an important component for permeable asphalt pavement. BISAR was used to analysis the interfacial stress under different conditions, and the rules of the tensile zone, the maximal tensile stress, the maximal interfacial shear stress and the corresponding point were obtained, which should be considered in selecting the WBL materials.

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