scholarly journals Laboratory determination of hydraulic anisotropy of dense graded asphalt concrete

2018 ◽  
Vol 38 (1) ◽  
pp. 67-73 ◽  
Author(s):  
Alberto Gaxiola-Hernández
Keyword(s):  
Asphalt Concrete ◽  
Asphalt Mixture ◽  
Point Of View ◽  
Design Stage ◽  
Test Results ◽  
Test Device ◽  
Hydraulic Anisotropy ◽  
Vehicle Loads ◽  
Constant Head

Dense graded asphalt concrete is widely used in roads as support structure for vehicle loads, however, is also used for hydraulic purposes in canal linings as well as faces and cores of dams. In the design stage of these constructions it is necessary to have the permeability data of the materials that will be used and, although in some cases it is sufficient to know this parameter in only one direction, in others it is necessary to have it in two directions. This research presents test results of axial permeability in constant head permeameter and the design a of radial permeability test device in asphalt concrete made for hydraulic purposes. As a result it was determined that the compaction process of asphalt concrete, applied in one direction, causes the material to have anisotropic behavior from the hydraulic point of view, resulting in anisotropy ratios 7.1 to 10.4, for the studied asphalt mixture.

scholarly journals Determination of Construction Parameters of Porous Ultra-Thin Overlays Based on Laboratory Compaction Studies

Materials ◽  
2020 ◽  
Vol 13 (20) ◽  
pp. 4496
Author(s):  
Jiahao Tian ◽  
Sang Luo ◽  
Ziming Liu ◽  
Xu Yang ◽  
Qing Lu
Keyword(s):  
Asphalt Concrete ◽  
Asphalt Mixture ◽  
Asphalt Mixtures ◽  
Combination Method ◽  
Compaction Temperature ◽  
Pavement Maintenance ◽  
Energy Equivalence ◽  
New Type ◽  
Better Than

To address the severe distresses of asphalt pavement, a new type of pavement maintenance treatment, porous ultra-thin overlay (PUTO) with small particle size was proposed. The PUTO has a thickness of 1.5–2.5 cm and a large void ratio of 18–25%. As a newly asphalt mixture, the structure characteristics differ from poor traditional pavement. Therefore, it is necessary to investigate the fabrication schemes in laboratory and on-site, respectively. In this study, the optimal fabrication schemes, including compaction temperature and number of blows of PUTO were determined based on Cantabro test and volumetric parameters. Then, the corresponding relationship between laboratory and on-site compaction work was then established based on the energy equivalent principle. On this basis, the numbers of on-site rolling passes and the combination method were calculated. The results show that increased compaction temperature and number of blows reduce the height and enhance the compaction of the Marshall sample. With the same temperature and number of blows, the raveling resistance of coarse gradation, Pavement Asphalt Concrete-1 (PAC-1) is better than that of fine gradation, Pavement Asphalt Concrete-2 (PAC-2), and the increased asphalt viscosity significantly improves the raveling resistance of the asphalt mixture. To ensure the scattering resistance and volumetric characteristic, the initial compaction temperature of the PAC-1 and PAC-2 should not be lower than 150 °C and 165 °C, respectively. Then, the laboratory compaction work and on-site compaction work were calculated and converted based on the principle of energy equivalence. Consequently, the on-site compaction combination of rolling machines for four asphalt mixtures was determined. According to the volumetric parameters, the paving test section proved that the construction temperature and the on-site rolling combination determined by laboratory tests are reasonable, and ultra-thin overlay has good structural stability, drainage, and skid resistance.

Preliminary Development of Indirect Tensile Tester Cooperated with Industrial Computered Tomography for Asphalt Mixture

2010 ◽  
Vol 168-170 ◽  
pp. 2654-2657
Author(s):  
Xiao Jun Li ◽  
Li Hua Jiang ◽  
Yun Xian Wang
Keyword(s):  
Tensile Strength ◽  
Asphalt Concrete ◽  
Hoop Stress ◽  
Asphalt Mixture ◽  
Cylindrical Sample ◽  
Vertical Stress ◽  
Test Results ◽  
Tensile Tester ◽  
Indirect Tensile ◽  
Mixture Sample

In this paper, a new Indirect tensile tester (IDT) which can be cooperated with Industrial Computered Tomography (IDT) is developed. The new tester uses a set of sliders to transfer the vertical stress to hoop stress which applied to a hollow cylindrical sample. The micro-crack will be appeared and propagated in the weakest direction of hollow cylindrical sample with the increase of vertical stress and tensile strength can calculated with the maximum vertical stress. Due to the existence of central slider, the stress state of hollow cylindrical sample will be kept even after unloading and the mixture sample would not have recovery when it is moved for scanning with ICT. The test results show that the combination of the developed ICT with IDT will help obtain more useful information on understanding the nature of asphalt concrete with different tensile damage stages.

A Unified Model for Micromechanics Damage in the Asphalt Concrete

2013 ◽  
Vol 577-578 ◽  
pp. 465-468 ◽  
Author(s):  
Michele Buonsanti ◽  
Giovanni Leonardi ◽  
Francesco Scoppelliti
Keyword(s):  
Asphalt Concrete ◽  
Distinct Element ◽  
Contact Point ◽  
Asphalt Mixture ◽  
Element Model ◽  
Adhesive Contact ◽  
Rigid Bodies ◽  
Point Of View ◽  
Normal Displacement ◽  
Binding Interface

The particles distinct element model has the consistency to model the mechanical behavior of the microscopic structures inside an asphalt mixture. The model assumes that the schematized granular constituents are in a contact point, considering the thin asphalt films as the binding elements. In this paper, we will model (at micro-scale) the damage to a surface in asphalt concrete under an impulsive load, considering binding, interface, viscosity and friction. Our aim is to reproduce the micro-damage due to detachment among the elementary components of the concrete in airports pavements.The proposed approach is mainly from a mechanical point of view, and a general model describing adhesive contact between rigid bodies is proposed. The intensity of adhesion is supposed to decrease under prescribed shear and normal displacement fields and comes by energy reduction, where the viscosity and friction contributes are taken in account.A numerical implementation by finite element procedures has been performed, and the outcome is presented.

scholarly journals Evaluating Marination Effect of Diluted Zycothermon Hot Mix Asphalt

2017 ◽  
Vol 3 (3) ◽  
pp. 18
Author(s):  
Ilham I. Mohammed
Keyword(s):  
Tensile Strength ◽  
Asphalt Concrete ◽  
Hot Mix Asphalt ◽  
Asphalt Mixture ◽  
Strength Test ◽  
Stability Test ◽  
Test Results ◽  
Great Range ◽  
Tensile Strength Test ◽  
Moisture Conditions

Sinceasphalt concrete undergo different failure problems at different temperature and moisture conditions and for years many scientists and researchers used different kinds of materials and variety of methods for improving the properties of asphalt concrete made with either basalt or limestone.So it became necessary to provide the best possible way to get rid of these failure problems.In this study diluted zycotherm nanomaterial at three different percentages by weight of aggregate used with two aggregate types, basalt and limestone, and asphalt concrete made with the marinated aggregate and later the properties of asphalt concrete were investigated after the marination.Indirect tensile strength test and retained stability test results were used to evaluate the marinating effect.As a result zycotherm dilution by weight of aggregate has changed the properties of asphalt mixture and improved to a great extent. From the results it can be concluded that rutting and fatigue problems decreased with a great range.

Evaluation of Pyrolized Carbon Black from Scrap Tires as Additive in Hot Mix Asphalt

1996 ◽  
Vol 1530 (1) ◽  
pp. 43-50 ◽  
Author(s):  
Taesoon Park ◽  
Brian J. Coree ◽  
C. W. Lovell
Keyword(s):  
Carbon Black ◽  
Asphalt Concrete ◽  
Resilient Modulus ◽  
Testing Machine ◽  
Asphalt Mixture ◽  
Asphalt Mixtures ◽  
Test Results ◽  
Reinforcing Agent ◽  
Dynamic Creep ◽  
Temperature Susceptibility

The viability of using pyrolized carbon black (CBp) derived from waste tires as a reinforcing agent in asphalt mixtures was evaluated. Commercial carbon black (CB) has been previously shown to reduce the rutting resistance, temperature susceptibility, and cracking propagation potential of asphalt concrete. It was believed that CBp could produce similar benefits; this belief has been confirmed by this study. Different ratios of CBp and CB (5, 10, 15, and 20 percent by weight of asphalt) were blended with two grades of asphalt (AC-10 and AC-20). The Marshall method, the gyratory testing machine, the dynamic creep testing (confined), the indirect tensile testing, and the resilient modulus test were performed. The test results of CBp mixtures were compared with results of CB and conventional mixtures. The analyses of test results show that the typical performance of CBp-modified asphalt mixtures is improved with respect to commercial CB and conventional mixtures. The rutting potential and the temperature susceptibility can be reduced by the inclusion of CBp in the asphalt mixture. A CBp content of 10 to 15 percent by weight of asphalt is recommended for improvement of asphalt concrete.

Construction Technique and Quality Control of Sup-25 Asphalt Mixture Used in Hao-Tong Highway

2014 ◽  
Vol 599 ◽  
pp. 287-290 ◽  
Author(s):  
Peng Cui ◽  
Yang Sang ◽  
Bao Quan Li ◽  
Hai Xia Zhang
Keyword(s):  
Quality Control ◽  
Water Permeability ◽  
Asphalt Concrete ◽  
Design Method ◽  
Asphalt Mixture ◽  
Construction Technology ◽  
Test Results ◽  
Construction Quality ◽  
Construction Technique ◽  
Marshall Test

In this paper, the asphalt mixture proportions for Hao-Tong highway was investigated using Sup25 gradation design method. Marshall Test was applied to estimate performance of asphalt concrete. Based on the actual project application, the methods of construction technology and construction quality control of Sup25 asphalt mixture were discussed in this paper. The test results showed that water permeability, degree of compaction and rutting of the Sup25 asphalt mixture layer meet the requirements of Chinese specification.

Determination of Hydrated Lime Content in Asphalt Mastic Incorporating High Temperature Performances

2014 ◽  
Vol 912-914 ◽  
pp. 81-84
Author(s):  
Liang Zhou
Keyword(s):  
High Temperature ◽  
Asphalt Mixture ◽  
Hydrated Lime ◽  
Test Results ◽  
Dynamic Shear ◽  
Addition Agent ◽  
Asphalt Mastic ◽  
Lime Content ◽  
Different Content

Different hydrated lime content in asphalt mastic greatly influences the performances of asphalt mixture. The aim of this paper is to study asphalt mastic made with different content of hydrated lime was used in Dynamic Shear Rheological and Viscosity Tests. The optimum hydrated lime content was proposed in terms of test results above. The results illustrated that hydrated lime was an appropriate addition agent which can improve asphalt mastic properties greatly, however, too much hydrated lime may result in the decrease of asphalt mixture performances.

Performance Evaluation of High-Modulus Asphalt Mixture

2011 ◽  
Vol 311-313 ◽  
pp. 2138-2141 ◽  
Author(s):  
Chun Ying Wu ◽  
Bin Jing ◽  
Xiao Yan Li
Keyword(s):  
Asphalt Concrete ◽  
Asphalt Mixture ◽  
Temperature Stability ◽  
Performance Comparison ◽  
Test Results ◽  
High Modulus ◽  
High Temperature Stability ◽  
Design Requirement ◽  
Bituminous Mixtures ◽  
Design Guide

According to LPC Bituminous Mixtures Design Guide, performance of several kinds of additives for high modulus asphalt mixture is evaluated by tests. It has done performance comparison among AC20, Sup20 and EME20 using AH70# asphalt. The results show that high modulus asphalt mixture EME2 has high temperature stability and anti-fatigue capability. The testing results in the article had proved that the existing China-made additives can also meet the requirement of High Modulus Asphalt Concrete (HMAC). The mix design of AC20 and Sup20 was done according to LPC Bituminous Mixtures Design Guide, test results are basically the same as EME20 and meet the design requirement. So it can consider using HMAC which satisfies China’s requirement in China.

scholarly journals Application of Millimeter 3D Automatic Paving System in Highway Engineering Construction

2020 ◽  
Vol 1 (2) ◽  
Author(s):  
Yi DONG ◽  
Jie WANG ◽  
Yijia MAO ◽  
Hua LI
Keyword(s):  
High Precision ◽  
Asphalt Concrete ◽  
Asphalt Mixture ◽  
Concrete Pavement ◽  
Control Technology ◽  
Test Results ◽  
Engineering Construction ◽  
Highway Engineering ◽  
Pavement Construction ◽  
Asphalt Concrete Pavement

In the construction of asphalt mixture pavement, there are many paving construction procedures, high requirements for machinery and personnel, unreasonable technology and so on. In this paper, the millimeter-scale 3D automatic paving control technology of asphalt mixture pavement is studied with an engineering example. From the analysis of the test results in the later stage of construction, it can be seen that the technology has achieved the goal of high precision paving, and the successful application of the technology provides valuable reference experience for similar asphalt concrete pavement construction in the future.

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