scholarly journals Research Concerning The Distribution of Temperature in Asphalt Mixtures with The Help of Thermo-Physical Characteristics for Laboratory Tests

2016 ◽  
Vol 5 (2) ◽  
pp. 28-36
Author(s):  
Paul Marc ◽  
Ciprian Costescu
Keyword(s):  
Laboratory Tests ◽  
Testing Temperature ◽  
Physical Characteristics ◽  
Asphalt Mixtures ◽  
Asphalt Pavements ◽  
Balance Condition ◽  
Reliable Assessment ◽  
Performance Predictions ◽  
Significant Performance ◽  
Time Required

Abstract The characterization of the material through laboratory tests performed on asphalt mixtures offers significant performance predictions for asphalt pavements only when the material temperature is correctly taken into consideration. This paper presents an analytical pattern which, based on the thermo-physical characteristics, can predict correctly the distribution of temperatures in the mass of asphalt mixtures. The paper also presents the organizational structure of laboratory testing, designed to validate the model for temperature determination. The temperature measurements are realized on a range of cylindrical samples at different moments in time, after submitting the sample from a low balance condition to a high balance condition by placing it in the environment precinct, according to the future test. In conclusion, the paper aims at realizing and developing a model as a practical instrument able to offer a reliable assessment concerning the time required in order to reach the testing temperature specified for the samples of asphalt mixtures for different laboratory trials.

Soft Asphalt Pavement – Solution for Low-Volume Roads in Changing Climate and Economy

2014 ◽  
Vol 934 ◽  
pp. 47-52 ◽  
Author(s):  
Audrius Vaitkus ◽  
Viktoras Vorobjovas ◽  
Donatas Čygas ◽  
Algis Pakalnis
Keyword(s):  
Asphalt Concrete ◽  
Laboratory Tests ◽  
Applied Research ◽  
Asphalt Pavement ◽  
Cost Effective ◽  
Asphalt Mixtures ◽  
Alternative Solution ◽  
Asphalt Pavements ◽  
Low Volume Roads ◽  
Low Volume

In Lithuania, it has always has been an important issue to find durable and cost-effective solutions for paving low-volume roads. The conventional asphalt concrete structures were built using paving grade bitumen with the penetration of 70/100 or 100/150 over the recent 20 years. The performance of those pavements was satisfactory. As an alternative solution, the use of soft asphalt pavements was proposed. This technology is widely used in Nordic countries. But in Lithuania it has never been applied. Research on the designed soft asphalt mixtures was carried out and the trial on-site sections were constructed. The results of laboratory tests and on-site research were positive and promising. Based on that, the technology could be considered as successfully implemented and good quality was achieved.

scholarly journals Investigation of Crack Propagation and Healing of Asphalt Concrete Using Digital Image Correlation

2019 ◽  
Vol 9 (12) ◽  
pp. 2459 ◽  
Author(s):  
Navid Hasheminejad ◽  
Cedric Vuye ◽  
Alexandros Margaritis ◽  
Bart Ribbens ◽  
Geert Jacobs ◽  
...  
Keyword(s):  
Digital Image Correlation ◽  
Digital Image ◽  
Asphalt Mixture ◽  
Asphalt Mixtures ◽  
Image Correlation ◽  
Asphalt Pavements ◽  
Rest Periods ◽  
Tensile Fatigue ◽  
Indirect Tensile ◽  
Time Required

The fatigue performance and healing ability of asphalt pavements are important for mixture design, rehabilitation, and maintenance of the roads. By analyzing these parameters in an asphalt mixture, it is possible to predict the crack formation and propagation in asphalt pavements and healing of these cracks during the rest periods. The healing effect in asphalt mixtures has been observed and verified by many researchers and different methods exist to evaluate this phenomenon. However, current methods are still inadequate to fully observe and quantify the healing phenomenon in asphalt mixtures. In this study, a digital image correlation (DIC) method is used to calculate the strain map on the surface of cylindrical asphalt specimens during the indirect tensile fatigue test. This strain map is used to detect the location of crack initiations and development of the microcracks during the experiments. Next, the specimens are unloaded and the temperature of the climate chamber is increased to 60 °C for 18 h to investigate the healing phenomenon on the surface of the specimens. It is observed that the strain reduces near the microcrack areas especially at the tip of the microcracks. Furthermore, using DIC it is possible to observe the healing rate and the minimum time required to heal the microcracks on the surface of the specimens.

Pavement Performance of Hot In-Place Recycling for Waste Asphalt Mixtures

2013 ◽  
Vol 668 ◽  
pp. 292-296
Author(s):  
Ya Li Ye ◽  
Chuan Yi Zhuang ◽  
Jia Bo Hu
Keyword(s):  
Asphalt Mixture ◽  
Asphalt Mixtures ◽  
Asphalt Pavements ◽  
Pavement Performance ◽  
Test Results ◽  
Technical Parameters ◽  
Stable Performance ◽  
Wheel Tracking Test ◽  
Asphalt Content ◽  
Wheel Tracking

With the early asphalt pavements have been into the stage of medium maintenance or overhaul, recycling is a very important way for waste asphalt mixtures. A sample was taken in the expressway from Huhhot to Baotou, and the waste mixtures were extracted from field and sieved; so that the new aggregates can be determined and mix design was carried. With the aid of the penetration, the softening point and the viscosity in 135°C test, the quantity of the regenerant and the asphalt content were ascertained. Through the high temperature stable performance, the anti-low temperature performance, the water stability and the Hamburg wheel-tracking test, the appropriate gradation and the optimum asphalt content were determined. The test results showed that the pavement performance of the waste asphalt mixture was enhanced obviously with hot in-place recycling, and it has achieved technical parameters for old asphalt mixture.

Biological control of Eutypa armeniacae. 4. Design and performance of an applicator for metered delivery of protective aerosols during pruning

1978 ◽  
Vol 18 (91) ◽  
pp. 287 ◽  
Author(s):  
MV Carter ◽  
LF Mullett
Keyword(s):  
Biological Control ◽  
Laboratory Tests ◽  
Field Tests ◽  
Piston Pump ◽  
Light Weight ◽  
Biological Matter ◽  
And Performance ◽  
Time Required ◽  
Aerosol Form ◽  
Three Components

The paper describes the development of a prototype applicator for delivery of protective mixtures, in aerosol form, to the wounded sapwood surfaces exposed during pruning. The equipment has three components : a 2 litre day-service tank, a light weight belt-mounted piston pump, and a modification of a standard pneumatic-powered pruning handgun. Laboratory tests of the applicator have proved its ability to deliver, repeatedly, a uniform dose of aerosol containing sufficient particulate chemical and/or biological matter to protect apricot sapwood from invasion by Eutypa armeniacae. Field tests of the equipment in two orchards demonstrated that from 90-100 per cent of wounds can be treated for the addition of less than 20 per cent to the time required to prune a tree. Over a period of three weeks' use no mechanical defects developed. Estimated volume of protective fluid required per day, treating up to 90 per cent of wounds, is less than two litres.

Experimental Study on Thermal Characteristics of Environment-Friendly Blocks with Water-Absorbing Polymer

2010 ◽  
Vol 658 ◽  
pp. 260-263
Author(s):  
Jong Bin Park ◽  
Ree Ho Kim ◽  
Sang Ho Lee ◽  
Hee Bum Pyun
Keyword(s):  
Construction Material ◽  
Bottom Ash ◽  
Thermal Characteristics ◽  
Asphalt Pavements ◽  
Water Runoff ◽  
Environment Friendly ◽  
Environmental Disasters ◽  
Storm Water Runoff ◽  
New Construction ◽  
Time Required

Urbanization together with increased population and industrialization has increased impermeable areas including asphalt and concrete pavement, leading to potential dangers of environmental disasters in urban area. While environmental pavements have been investigated to mitigate these problems in some countries such as Germany and Japan, little work has been done in Korea. Furthermore, most studies on environmental pavements have focused on permeable asphalt pavements. This study was intended to develop new materials for water-absorbing pavement blocks to control pavement temperature and storm water runoff. Bottom ash, which is a coal combustion by-products, was used as a composing material for these blocks. A polymer with water absorption ratio of 76% was used as a water-retention material for the pavement blocks. The effect of block compositions on mechanical characteristics, compressive strength and porosity were examined as well as thermal characteristics. This water-absorbing polymer is likely to be suitable to be used with the bottom ash blocks. The time required to fill the pores of the blocks with the polymer ranged from 9 to 14 sec, indication that the polymer can be readily applied to the blocks. The final products with optimum compositions satisfied the Korean Standard for blocks and possessed an excellent water-retentive ability. Experiments are ongoing to measure the properties of the blocks for further application as a new construction material.

Laboratory Properties Evaluation of Wearing Course Asphalt Mixtures Incorporating RAP Materials

2011 ◽  
Vol 305 ◽  
pp. 398-401
Author(s):  
Lan Yun Chen ◽  
Xin Qiu ◽  
Xin Kuan Wang ◽  
Qing Yang
Keyword(s):  
Natural Resources ◽  
Environmental Protection ◽  
Laboratory Tests ◽  
Asphalt Mixtures ◽  
Land Conservation ◽  
Material Consumption ◽  
Engineering Characteristics ◽  
New Material

Using RAP to reproduce new mixtures helps to reduce new material consumption, minimizes the exploitation of natural resources and brings vast benefit in land conservation and environmental protection. The main objectives of this study is to conduct laboratory tests on RAP mixtures with different RAP content, to comprehensively evaluate their engineering characteristics, then to recommend the best suitable RAP mixtures as the local paving materials.

scholarly journals Assessment of Skid Resistance of Asphalt Mixtures in Laboratory Conditions

2012 ◽  
Vol 58 (4) ◽  
pp. 521-534 ◽  
Author(s):  
W. Gardziejczyk ◽  
M. Wasilewska
Keyword(s):  
Asphalt Concrete ◽  
Laboratory Tests ◽  
Asphalt Mixtures ◽  
Road Surface ◽  
Skid Resistance ◽  
Mastic Asphalt ◽  
Laboratory Conditions ◽  
University Of Technology ◽  
Road Surfaces ◽  
Stone Mastic Asphalt

AbstractThe aggregate applied for the wearing course has a significant influence on skid resistance of road surfaces. However, it is difficult to evaluate the behaviour of road surface in use on the basis of the Polished Stone Value (PSV) determined for the aggregate according to the so called ‘British method’. The British method, which is currently used in many countries, does not allow to determine the influence of neither the grain size of the aggregate nor the type of the wearing course on skid resistance of road surface. The present paper suggests a method for evaluation of the British Pendulum Number (BPN) for road surfaces in laboratory conditions. The authors assumed the BPN for polished slabs, made from asphalt mixtures, as the criterion. The index was measured with the British Pendulum Tester. The simulation of the process was conducted on research stand (called slab polisher) built at Bialystok University of Technology (BUT). The results of laboratory tests indicate that surfaces from asphalt concrete (AC) have slightly higher values of BPN in comparison with the values determined for surfaces made from stone mastic asphalt (SMA).

Crack Propagation Behavior of Asphalt Concrete; Part I: A Study into Influence of Different Materials

2008 ◽  
Vol 385-387 ◽  
pp. 297-300
Author(s):  
Tao Xie ◽  
Ze Zhong Jiang ◽  
Yan Jun Qiu ◽  
Bo Lan
Keyword(s):  
Crack Propagation ◽  
Fracture Resistance ◽  
Failure Process ◽  
Asphalt Mixtures ◽  
Asphalt Pavements ◽  
Cracking Behavior ◽  
Strain Behavior ◽  
Propagation Behavior ◽  
Maintenance And Rehabilitation ◽  
Asphalt Materials

The fracture resistance of asphalt materials significantly influences the service life of asphalt pavements and consequently affects the maintenance and rehabilitation costs of the pavement network. Therefore, there is significant interest in understanding the mechanism of fracture in asphalt pavements and in developing analysis tools that would lead to the selection of asphalt materials with increased fracture resistance. Study of cracking behavior of asphalt mixtures should be conducted in a micro-scale level to have a real simulation of crack propagation. Using SIEMENS SOMATOM plus X-ray CT (computerized tomography) and multi-functional testing rig, a dynamic observation of cracking propagation of hot mix asphalt was conducted in this research. Failure process under compressive pressure was recorded using CT images and CT numbers. The direct responses in density change of Marshall Samples under a CT-compressive process are change of CT numbers. Cracking propagation in the samples can be clearly observed and failure mode and stress-strain behavior can then be simulated. The tests reported provide important theoretical fundamentals to study the cracking behavior and failure mechanism of asphalt mixtures.

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