Time filter

Source Type

Zhang Q.,Xi'an University of Technology | Xie L.-B.,Xi'an University of Technology | Li Y.-W.,Shijiazhuang Transportation Bureau | He Y.-H.,Hebei Traffic Planning and Design Institute | Liu J.,Hebei Traffic Planning and Design Institute
Xi'an Jianzhu Keji Daxue Xuebao/Journal of Xi'an University of Architecture and Technology | Year: 2011

Waste plastic is reused in pavement engineering in this research. The purpose of the study is to probe the possibility of using waste plastic in asphalt mixture as a kind of modifier so as to find a way to solve the problem of the waste plastic disposal. High Density Polyethylene plastic bags obtained from supermarket were shredded into pieces and were added into asphalt mixture at three percentages of 2%, 5% and 8%. The corresponding control samples were also made and tested. Three different temperatures were used (4°C, 21.3°C and 39.2°C) and the frequencies ranged from 0.1 Hz to 25 Hz in this dynamic modulus test. When compared with the test results of the control samples, almost all the dynamic modulus of the plastic modified samples(except 4 results) are greater than those of the control samples. No regular pattern is shown in the test results of the phase angle. Modified asphalt mixture with 2% plastic is of the greatest dynamic modulus and phase angle.

Li Y.-W.,Shijiazhuang Transportation Bureau | Li Y.-W.,Tianjin University | Zhang Q.,Xi'an University of Architecture and Technology | Xie L.-B.,Xi'an University of Architecture and Technology | And 2 more authors.
Gongneng Cailiao/Journal of Functional Materials | Year: 2012

Accurate temperature field estimation is crucial to asphalt mixture's visco-elastic analysis and rutting depth calculation. Temperature filed estimation is closely related to pavement layers' thermal physical parameters. Therefore, precise testing of asphalt mixture physical parameters becomes more and more important. Among the thermal physical parameters, testing of thermal conductivity is given special attention because it's one of the most commonly used parameters of asphalt mixture. Hot wire method is considered a suitable method in testing HMA thermal conductivity coefficient and its testing principle is introduced. Thermal conductivities of four types of asphalt mixtures with different gradation are tested using transient hot wire method. And its influencing factors are analyzed. An asphalt pavement structure is modeled and its temperature field distribution was calculated using finite element software ABAQUS. Based on the calculation, it is found that asphalt pavement temperature field distribution changes with the change of thermal conductivities of the top layer, mid layer and bottom layer. It can be seen from the simulation result that thermal conductivity of the top layer has a significant influence on temperature distribution of the pavement structure. It can be anticipated that it's possible to improve asphalt pavement temperature field by changing top layer thermal conductivity.

Yang S.,University of Arkansas | Braham A.,University of Arkansas | Wang L.,Hebei Traffic Planning and Design Institute | Wang Q.,Hebei Traffic Planning and Design Institute
Construction and Building Materials | Year: 2016

Significant research has been performed in the area of Recycled Asphalt Pavement (RAP) and Warm Mix Asphalt (WMA). This research has often looked at the influence of aging and moisture on cracking and rutting, but there is limited research available that looks at the combination of aging and moisture on both cracking and rutting. This research investigated the effects of RAP and chemical modified WMA on laboratory performance tests including: cracking, rutting, compactability, moisture conditioning, and aging. Based on the test results, WMA with RAP performed similar to Hot Mix Asphalt (HMA) with RAP in cracking and rutting resistance even though the WMA had lower mixing and compacting temperatures and a reduced binder content. In addition, WMA with RAP had similar compaction characteristics as HMA with RAP. © 2016 Elsevier Ltd. All rights reserved.

Loading Hebei Traffic Planning and Design Institute collaborators
Loading Hebei Traffic Planning and Design Institute collaborators