Studying the Early Cracking Behavior of Asphalt Concrete 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.

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Full-Scale Evaluation of Relatively Thin Airfield Pavements

Transportation Research Record Journal of the Transportation Research Board ◽

10.1177/0361198120939099 ◽

2020 ◽

Vol 2674 (10) ◽

pp. 658-669

Author(s):

W. Jeremy Robinson ◽

Jeb S. Tingle ◽

Carlos R. Gonzalez

Keyword(s):

Asphalt Concrete ◽

Test Section ◽

Concrete Surface ◽

Full Scale ◽

Test Items ◽

Pavement Structures ◽

Base Course ◽

And Performance ◽

Rutting Behavior ◽

Aggregate Base

A full-scale airfield pavement test section was constructed and trafficked by the U.S. Army Engineer Research and Development Center (ERDC) to evaluate the performance of relatively thin airfield pavement structures. The test section consisted of four test items that included three asphalt pavement thicknesses and two different aggregate base courses. The test items were subjected to simulated aircraft traffic to evaluate their response and performance to realistic aircraft loads. Rutting behavior, instrumentation response, and falling weight deflectometer response were monitored at selected traffic intervals. It was found that the performance of the airfield pavement sections were most sensitive to aggregate base course properties, where a 50% reduction in base course strength resulted in a 99% reduction in allowable passes. The data suggested that when sufficient asphalt thickness is not provided, the failure mechanism shifted from subgrade failure to base course failure, particularly at higher subgrade CBR values. In addition, the number of aircraft passes sustained was less than that predicted by current Department of Defense (DOD) methods that include assumptions of a high-quality aggregate base and a minimum asphalt concrete thickness. The results of this study were used to extend existing DOD pavement design and evaluation techniques to include the evaluation of airfield pavement sections that do not meet the current criteria for aggregate base quality and minimum asphalt concrete surface thickness. These performance data were used to develop a new base failure design curve using existing stress-based design criteria.

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Experimental Evaluation of the Influence of Aggregate Strength on the Flexural Cracking Behavior of Epoxy Asphalt Mixtures

Materials ◽

10.3390/ma13081876 ◽

2020 ◽

Vol 13 (8) ◽

pp. 1876

Author(s):

Wei Xu ◽

Xiaoshu Wei ◽

Jintao Wei ◽

Zhengxiong Chen

Keyword(s):

Asphalt Concrete ◽

High Strength ◽

Bending Test ◽

Steel Bridge ◽

Test Results ◽

Cracking Resistance ◽

Cracking Behavior ◽

Epoxy Asphalt ◽

Fracture Area ◽

Aggregate Strength

The flexural cracking resistance of an asphalt concrete mixture used in a steel bridge deck pavement needs to be higher than that of one used in ordinary pavement. In this study, mechanical experimental tests were used to evaluate the influence of the aggregate strength on the flexural cracking behavior of epoxy asphalt concrete (EAC). The aggregate fracture area of beam cross sections was quantitatively analyzed by digital image processing, and crack propagation in the mixture was analyzed using fracture mechanics theory. The bending test results showed that the EAC containing high-strength aggregates exhibited the highest flexural cracking resistance among all of the aggregate mixtures under the same conditions. The use of high-strength aggregates led to a reduction in the aggregate fracture area, thereby improving the flexural cracking resistance of the mixture. The aggregate strength had a significant influence on the flexural cracking propagation behavior of the mixture. Fatigue test results at strain-controlled levels of 600–1200 με and 15 °C showed that the aggregate strength had no evident influence on the fatigue properties of the EAC. It is recommended that high-strength aggregates are used to increase the fracture resistance of aggregates and the flexural crack resistance of EACs.

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Coupled Numerical Analysis of the Anti-Crack Mechanism for Open-Graded Large Stone Asphalt Mixes

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.79-82.1149 ◽

2009 ◽

Vol 79-82 ◽

pp. 1149-1152

Author(s):

Hong Bing Guo ◽

Shuan Fa Chen

Keyword(s):

Finite Element ◽

Asphalt Concrete ◽

Asphalt Pavement ◽

Rigid Base ◽

Reflective Cracking ◽

Large Stone ◽

Concrete Base ◽

Test Road ◽

Cracking Performance ◽

Pavement Structure

The reflective cracking in asphalt surface is a technical problem that exists in the semi-rigid base asphalt pavement structure and the rigid base asphalt pavement structure, how to control its emergence and development is still a major problem for road engineering. At present, researches on the anti-cracking performance for Open-graded Large Stone asphalt Mix (OLSM) in China almost remain in the test road observations, very few study the mechanism of its anti-cracking from the mechanical point. Aiming at this problem, a method of using OLSM as the cracking relief layer is proposed, large mineral aggregate, low asphalt content and a great deal of void in OLSM can dissipate or absorb stress and strain around the crack. The 3-D finite element method is used to analyze the crack-alleviating layer of ordinary asphalt concrete and OLSM, and the large-scale commercial finite element software of ABAQUS is used to do numerical simulation analysis for the lean concrete base asphalt pavement structure with OLSM, the analysis result indicates that temperature-load coupling stress of OLSM are less than that of ordinary asphalt concrete. Depending on the test road on an expressway, research on the anti-crack mechanism of OLSM has been conducted. The investigation of the test road and the result of the theoretical calculation indicate that OLSM can prevent lean concrete base asphalt pavement from the reflective cracking effectively, OLSM has good anti-cracking performance, it is an effective material to alleviate the reflective cracking. As the crack-alleviating layer, OLSM can significantly enhance the anti-cracking ability of the semi-rigid base asphalt pavement structure and the rigid base asphalt pavement structure.

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Instrumentation of a Geosynthetic-Reinforced Flexible Pavement System

Transportation Research Record Journal of the Transportation Research Board ◽

10.3141/1596-05 ◽

1997 ◽

Vol 1596 (1) ◽

pp. 31-38

Author(s):

Steven W. Perkins ◽

Joseph A. Lapeyre

Keyword(s):

Asphalt Concrete ◽

Test Section ◽

Flexible Pavement ◽

Design Tool ◽

Life Cycle Costs ◽

Site Specific ◽

Program Of Study ◽

Traffic Loads ◽

Base Course

Geosynthetics have been proposed and used to reinforce base course layers in flexible pavement sections to reduce base course thickness, or life-cycle costs, or both. Studies show conflicting results regarding the level to which geosynthetics can improve the performance of flexible pavements. To examine the reinforcement role of geosynthetics, a program of study has been initiated to define the mechanisms of base course reinforcement, to define and quantify the effect of site-specific parameters on the level of improvement observed, and to devise a design tool that can be readily applied in practice. This program will eventually involve the instrumentation of a full-scale pavement subjected to moving traffic loads, the success of which is essential to meeting the three objectives. As a first examination of the performance of proposed instruments, a pilot test section was constructed and monitored for approximately 3 months. The test section was chosen and constructed not necessarily to establish geosynthetic performance but rather to evaluate instrument installation techniques and subsequent instrument performance. Instruments designed to measure strain in the geosynthetics, base course, and asphalt concrete were included.

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KARAKTERISTIK ASPHALT CONCRETE (AC) DENGAN AGREGAT SUNGAI SERANG KABUPATEN KULON PROGO BERDASARKAN KINERJA SECARA LABORATORIUM

CivETech ◽

10.47200/civetech.v15i2.722 ◽

2020 ◽

Vol 15 (2) ◽

pp. 60-72

Author(s):

Suryanto Suryanto

Keyword(s):

Asphalt Concrete ◽

Concrete Base

Pemeriksaan (pengujian) setiap saat dan lokasi terhadap agregat sebagai material perkerasan jalan sangat diperlukan mengingat dapat sebagai kontrol atau pembanding dari design (perencanaan) yang telah dilaksanakan dan sebagai gambaran atau perkiraan untuk perencanaan yang akan datang. Untuk mengetahui karakteristik dari Asphalt Concrete (AC) dengan agregat sungai Serang berdasarkan kinerja secara laboratorium dalam fungsinya sebagai Asphalt Concrete-Wearing Course (AC-WC), Asphalt Concrete-Binder Course (AC-BC), dan Asphalt Concrete-Base (AC-Base) dilakukan pengujian dengan metode Marshall di laboratorium dan digunakan peubah agregat dan kadar aspal, yang terdiri dari uji aspal, agregat, dan tes Marshall. Karakteristik Asphalt Concrete (AC) meliputi penyerapan aspal, VIM, VMA, VFA, stabilitas Marshall, kelelehan (flow), kuotien Marshall, stabilitas Marshall sisa setelah perendaman selama 24 jam, 60 ºC , dan VIM pada kepadatan membal (refusal). Kadar aspal tengah / ideal untuk AC agregat sungai Serang berdasarkan rumus Spesifikasi Depkimpraswil 2002 tidak berbeda secara signifikan dengan kadar aspal optimum dari gambar hubungan kadar aspal dan parameter Marshall. Karakteristik (sifat) dari Asphalt Concrete (AC) dengan agregat sungai Serang dalam bentuk Asphalt Concrete-Wearing Course (AC-WC), Asphalt Concrete-Binder Course (AC-BC), dan Asphalt Concrete-Base (AC-Base) memenuhi persyaratan Spesifikasi Depkimpraswil 2002.

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Influences by Air Voids on the Low-Temperature Cracking Property of Dense-Graded Asphalt Concrete Based on Micromechanical Modeling

Advances in Materials Science and Engineering ◽

10.1155/2016/6942696 ◽

2016 ◽

Vol 2016 ◽

pp. 1-10 ◽

Cited By ~ 5

Author(s):

Tao Ma ◽

Yao Zhang ◽

Hao Wang ◽

Xiaoming Huang ◽

Yongli Zhao

Keyword(s):

Low Temperature ◽

Asphalt Concrete ◽

Three Dimensions ◽

Micromechanical Modeling ◽

Void Content ◽

Cracking Behavior ◽

Air Voids ◽

Low Temperature Cracking ◽

Air Void ◽

Air Void Content

This study characterized the impacts of air voids on the low-temperature cracking behavior of dense-graded asphalt concrete. Virtual low-temperature bending beam test for dense-graded asphalt concrete was built and executed by discrete element method and PFC3D (particle flow code in three dimensions). Virtual tests were applied to analyze the impacts by content, distribution, and size of air voids on the low-temperature properties of dense-graded asphalt concrete. The results revealed that higher air void content results in worse low-temperature property of dense-graded asphalt concrete, especially when the air void content exceeds the designed air content; even with the same designed air void content, different distributing condition of air voids within asphalt concrete leads to different low-temperature properties of asphalt concrete, especially when the air void content in the central-lower part of testing sample varies. Bigger size of single air void which tends to form interconnected air voids within asphalt concrete has more harmful impacts on the low-temperature properties of asphalt concrete. Thus, to achieve satisfied low-temperature properties of dense-graded asphalt concrete, it is critical to ensure the designed air void content, improve the distribution of air voids, and reduce the interconnected air voids for dense-graded asphalt concrete.

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Verifying Moisture Damage Impact in Asphalt Concrete with the Aid of Nondestructive Test NDT

Advances in Sciences and Engineering ◽

10.32732/ase.2020.12.1.13 ◽

2020 ◽

Vol 12 (1) ◽

pp. 13-20

Author(s):

Saad Issa Sarsam ◽

Nazar Sajad Kadium

Keyword(s):

Elastic Modulus ◽

Asphalt Concrete ◽

Ultrasonic Pulse Velocity ◽

Moisture Damage ◽

Ultrasonic Pulse ◽

Pulse Velocity ◽

Coefficient Of Determination ◽

Before And After ◽

Base Course ◽

The Impact

One of the major concerns of pavement durability is its susceptibility to moisture damage. In this investigation, non-destructive test NDT has been implemented to detect the moisture damage issue. Asphalt concrete specimens were prepared using the traditional Marshall method for wearing, binder and asphalt stabilized base course. Specimens were traversed by ultrasound pulse velocity before and after practicing the moisture damage procedure. The variation of dynamic and elastic modulus before and after the moisture damage was considered and related to tensile strength ratio TSR. It was noted that the pulse velocity decline by (11, 11.2 and 16.4) % and the dynamic modulus declines by (28, 6.6 and 28.5) % for asphalt concrete wearing, binder and base courses respectively after moisture damage. The elastic modulus exhibits no significant variation after moisture damage for wearing course while it declines by (9 and 11.7) % for binder and base courses respectively after moisture damage. It was concluded that the elastic and dynamic moduli were unable to clearly distinguish the impact of moisture damage, whereas the Seismic modulus calculated from the Ultrasonic Pulse Velocity test was effective in distinguishing such impact. The linear equation obtained with good coefficient of determination can explain 74 % of the variation in the seismic modulus after moisture damage.

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