Changes in the ultrasonic characteristics of the surface layer made of asphalt concrete

1997 ◽  
Vol 30 (4) ◽  
pp. 256-257
Keyword(s):  
Surface Layer ◽  
Asphalt Concrete

scholarly journals Analisis Kebutuhan dan Biaya Alat Berat untuk Pekerjaan Pemadatan Lapisan Permukaan Street-Race Circuit Mandalika

2021 ◽  
pp. 1-8
Author(s):  
A. Fihani ◽  
Hasyim Hasyim ◽  
I.D.M.A. Karyawan
Keyword(s):  
Surface Layer ◽  
Asphalt Concrete ◽  
Road Surface ◽  
Pneumatic Tire ◽  
Total Cost ◽  
Air Compressor ◽  
The Road ◽  
Heavy Equipment ◽  
Dump Trucks ◽  
Base Course

The Street-Race Circuit is being built in the Mandalika Tourism Special Economic Zone (KEK), Central Lombok, West Nusa Tenggara. The construction is targeted to be completed, before the MotoGP event on this circuit is implemented in 2021. One of the infrastructure related to this, which also really needs to be built to support the smooth running of the 2021 MotoGP is the development of access to the circuit location. The analysis carried out includes the calculation of heavy equipment productivity. Heavy equipment productivity is determined based on cycle times, production per hour, number of heavy equipment used, the amount of operating costs per hour. The analysis was carried out for the road surface layer work, namely the Asphalt Concrete Base Course (AC-BC) work. Based on the results of the analysis, it was found that the production for 1 unit of asphalt mixing plant (AMP) was 49.80 tons/hour and 9 units of dump trucks were 2.34 tons/hour. The spreader using the asphalt finisher can spread 109.18 tons/hour. As for the compactor, which is 18.55 tons/hour for 2 units of tandem rollers and 27.47 tons/hour for 1 unit of pneumatic tire roller. Other equipment is 9.96 m2/hour for air compressor and 2.74 liter/hour for asphalt sprayer. Meanwhile, in the Asphalt Concrete Wearing Course (AC-WC) work, several tools have the same productivity as the AC-BC job, namely asphalt mixing plant, air compressor and asphalt sprayer. Meanwhile, 13 units of Dump Trucks amounted to 2,338 tons/hour, 1 unit of asphalt finisher of 72,787 tons/hour, 3 units of tandem rollers of 12,367 tons/hour, and 1 unit of pneumatic tire roller of 18.31 tons/hour. The total cost of using heavy equipment for road surface layer work is Rp. 4,967,657,344. The total cost based on the contract document is Rp. 5,042,082,622. So that there is a difference in costs of Rp. 74,425,278.

Study on Mechanical Behavior of Asphalt Concrete Pavements with Non-Uniformity Gradient Materials

2011 ◽  
Vol 243-249 ◽  
pp. 4334-4338
Author(s):  
Ke Zhen Yan ◽  
Zou Zhang
Keyword(s):  
Surface Layer ◽  
Asphalt Concrete ◽  
Mechanical Characteristics ◽  
Damage Mechanism ◽  
Asphalt Mixtures ◽  
Concrete Pavements ◽  
The Finite Element Method ◽  
Gradient Materials ◽  
Pavement Damage ◽  
Asphalt Concrete Pavement

Generally speaking, the asphalt concrete pavement will be affected by the temperature and aging when it is in the use, which makes the modulus of asphalt mixtures change as non-uniformity gradient. This paper assumes the different changes on the modulus of surface layer with different gradient and then researched the mechanical characteristics of asphalt concrete pavements with cracks and no cracks by the finite-element method . Moreover, the research focused on the stress and K I & K II of the asphalt concrete pavements affected by the modulus of surface layer changed as non-uniformity gradient. The results demonstrated that the larger the gradient on the modulus of the surface layer,the bigger the tensile stress and K I and K II of the asphalt concrete pavements, and K IIis even much bigger than K I. Consequently, it is of great importance to take into account the effect of the modulus of surface layer changed as non-uniformity gradient. It also makes a great significance for the revision of pavement design and the analysis of pavement damage mechanism.

In Situ Evaluation of Fatigue Damage Growth and Healing of Asphalt Concrete Pavements Using Stress Wave Method

1997 ◽  
Vol 1568 (1) ◽  
pp. 106-113 ◽  
Author(s):  
Yongon Kim ◽  
Y. Richard Kim
Keyword(s):  
Surface Layer ◽  
Fatigue Damage ◽  
Stress Wave ◽  
Asphalt Concrete ◽  
Kernel Method ◽  
Asphalt Pavements ◽  
Stress Wave Propagation ◽  
Damage Growth ◽  
Rest Periods

Accurate in situ evaluation of the changes in material properties of an asphalt surface layer due to fatigue loading and rest periods is important for a better understanding of fatigue mechanisms of asphalt concrete in the field and therefore more realistic prediction of the fatigue life of asphalt pavements. A nondestructive technique based on the stress wave propagation method is presented as a means of measuring the changes in the “apparent” modulus of an asphalt surface layer due to fatigue damage growth and healing during rest periods. The method was applied to four asphalt pavements in the FHWA Turner Fairbank Highway Research Center that were loaded by the Accelerated Loading Facility to induce fatigue damage. The dispersion analysis is performed using the Short Kernel Method on the wave transients measured at different loading cycles and after rest periods. The results indicate that ( a) the test and analysis technique used provides a sensitive means of evaluating the changes in asphalt surface layer properties during fatigue loads and rest periods, ( b) the elastic modulus of the asphalt layer decreases as the number of loading cycles increases in an S-shape decaying curve, and ( c) the effective modulus of the asphalt layer increases because of the introduction of rest between loading cycles.

scholarly journals Karakteristik Marshall Campuran Asphalt Concrete Binder Course (AC-BC) Yang Mengandung Cangkang Kelapa Sawit Sebagai Agregat Kasar

2019 ◽  
Vol 16 (2) ◽  
pp. 113-123
Author(s):  
Syaifullah Alli ◽  
Mukhlis Mukhlis ◽  
Lusyana Lusyana ◽  
Fauna Adibroto ◽  
Enita Suardi
Keyword(s):  
Surface Layer ◽  
Palm Oil ◽  
Oil Palm ◽  
Asphalt Concrete ◽  
Coarse Aggregate ◽  
Asphalt Mixture ◽  
Minimum Thickness ◽  
Palm Shell ◽  
Oil Palm Shell ◽  
The Stability

AC-BC coating is one type of hot mix asphalt with a minimum thickness of 4 cm. The most important characteristic of this mixture is the stability of the surface layer where the surface layer must be able to accept all types of work loads. As a foundation layer, the asphalt content it contains must be sufficient so that it can provide a waterproof coating. The aggregate used is rather rough compared to the surface wear layer. The aggregate requirement that dominates in the asphalt mixture makes us research what materials can be used as a mixture in the asphalt mixture. Palm oil waste provides an alternative opportunity as a material making up the asphalt mixture. The intended waste is oil palm shell which can be used as a substitute for coarse aggregate in asphalt mixture. The purpose of this study is to obtain the ACO BC mix KAO calculation without using an oil palm shell and using a palm oil shell with variations of 2.5%, 5%, 7.5%, 10%, 12.5%, and 15% as substitution of coarse aggregate and know the effect of adding palm shells to the mixture of test specimens on Marshall parameter values. Before the manufacture of test specimens, the materials are tested in advance in accordance with the 2010 Revised 3 General Specifications. 3. The addition of oil palm shells to the asphalt mixture showed an increase in KAO value. Based on the results of the study, the oil palm shell was suitable as an additive to the Asphalt Concrete-Binder Course (AC-BC) mixture because it met the requirements of the 2010 Revised 3 General Bina Marga General Specifications.Keywords: mixture of AC-BC, oil palm shells, KAO, Marshall parameters

scholarly journals Dynamic Response Analysis of Rutting Resistance Performance of High Modulus Asphalt Concrete Pavement

2018 ◽  
Vol 8 (12) ◽  
pp. 2701 ◽  
Author(s):  
Chundi Si ◽  
Hang Cao ◽  
Enli Chen ◽  
Zhanping You ◽  
Ruilan Tian ◽  
...  
Keyword(s):  
Surface Layer ◽  
Thermal Stress ◽  
Temperature Variation ◽  
Asphalt Concrete ◽  
Asphalt Pavement ◽  
Moving Loads ◽  
High Modulus ◽  
Rutting Resistance ◽  
Resistance Performance ◽  
Continuous Temperature

In order to systematically study the rutting resistance performance of High-Modulus Asphalt Concrete (HMAC) pavements, a finite element method model of HMAC pavement was established using ABAQUS software. Based on the viscoelasticity theory of asphalt, the stress and deformation distribution characteristics of HMAC pavement were studied and compared to conventional asphalt pavement under moving loads. Then, the pavement temperature field model was established to study the temperature variation and the thermal stress in HMAC pavement. Finally, under the condition of continuous temperature variation, the creep behavior and permanent deformation of HMAC pavement were investigated. The results showed that under the action of moving loads, the strain and displacement generated in HMAC pavement were lower than those in conventional asphalt pavement. The upper surface layer was most obviously affected by outside air temperature, resulting in maximum thermal stress. Lastly, under the condition of continuous temperature change, HMAC pavement could greatly reduce the deformation of asphalt material in each surface layer compared to conventional asphalt pavement.

The oxidation of Inconel alloy MA754 at low oxidation potential

1983 ◽  
Vol 41 ◽  
pp. 218-219
Author(s):  
D. N. Braski ◽  
P. D. Goodell ◽  
J. V. Cathcart ◽  
R. H. Kane
Keyword(s):  
Surface Layer ◽  
Oxidation Potential ◽  
Metal Interface ◽  
Elevated Temperature Strength ◽  
Surface Conditions ◽  
Inconel Alloy ◽  
Inco Alloy ◽  
Resistance To Oxidation ◽  
Oxide Particles ◽  
Cold Worked

It has been known for some time that the addition of small oxide particles to an 80 Ni—20 Cr alloy not only increases its elevated-temperature strength, but also markedly improves its resistance to oxidation. The mechanism by which the oxide dispersoid enhances the oxidation resistance is being studied collaboratively by ORNL and INCO Alloy Products Company.Initial experiments were performed using INCONEL alloy MA754, which is nominally: 78 Ni, 20 Cr, 0.05 C, 0.3 Al, 0.5 Ti, 1.0 Fe, and 0.6 Y2O3 (wt %).Small disks (3 mm diam × 0.38 mm thick) were cut from MA754 plate stock and prepared with two different surface conditions. The first was prepared by mechanically polishing one side of a disk through 0.5 μm diamond on a syntron polisher while the second used an additional sulfuric acid-methanol electropolishing treatment to remove the cold-worked surface layer. Disks having both surface treatments were oxidized in a radiantly heated furnace for 30 s at 1000°C. Three different environments were investigated: hydrogen with nominal dew points of 0°C, —25°C, and —55°C. The oxide particles and films were examined in TEM by using extraction replicas (carbon) and by backpolishing to the oxide/metal interface. The particles were analyzed by EDS and SAD.

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