Xiaoyang Jia

Laboratory Performance Evaluation of Warm-Mix Asphalt Containing High Percentages of Reclaimed Asphalt Pavement

This study evaluated the rutting resistance, moisture susceptibility, and fatigue resistance of warm-mix asphalt (WMA) mixtures containing high percentages of reclaimed asphalt pavement (RAP) through laboratory performance tests. The WMA mixtures were plant produced with a foaming technology commonly used in the United States. RAP content ranged from 0% up to 50%. Laboratory performance tests included the asphalt pavement analyzer rutting test, the Hamburg wheel-tracking test, the tensile strength ratio test, the Superpave® indirect tension test, and the beam fatigue test. For comparison purposes, hot-mix asphalt mixtures containing 0% and 30% RAP were also evaluated and compared with WMA. The laboratory test results indicated that WMA mixtures with high percentages of RAP exhibited higher resistance to rutting, better resistance to moisture damage, and better fatigue performance.

Influence of Waste Engine Oil on Asphalt Mixtures Containing Reclaimed Asphalt Pavement

This paper presents the results from a laboratory study in which the influence of waste engine oil on the performance of hot-mix asphalt (HMA) containing reclaimed asphalt pavement (RAP) was evaluated. The lab test consists of binder test and mixture test. For binder test, the extracted RAP binder was blended with virgin binder and waste oil to investigate the rheological properties as well as fatigue properties. The waste engine oil was collected from a local auto repair shop. Performance Grade 64-22 was selected as virgin binder. For mixture test, the HMA containing RAP was evaluated at three RAP contents [(1) 0%, (2) 25%, and (3) 40%] and three waste oil contents [(1) 0%, (2) 2%, and (3) 5%]. Binder master curves, linear amplitude sweep, Superpave indirect tension, beam fatigue, and asphalt pavement analyzer rutting tests were conducted to evaluate the engineering properties of asphalt and asphalt mixtures. The results from the research reported in this paper indicated that the incorporation of waste engine oil into HMA with RAP may offset the increase of stiffness caused by aged binder in RAP. The inclusion of waste engine oil decreased optimum asphalt content, and reduced rut resistance. Meanwhile, it may also have limited improvements on fatigue resistance of the mixtures.

Effectiveness Analyses of Flexible Pavement Preventive Maintenance Treatments with LTPP SPS-3 Experiment Data

AbstractThe present study analyzes the effectiveness of preventive maintenance (PM) treatments of flexible pavements utilizing data obtained from the specific pavement study 3 (SPS-3) of the long-term pavement performance (LTPP) program online database. The PM treatments included in this study are thin hot mix asphalt (HMA) overlay, chip seal, slurry seal, and crack seal. International roughness index (IRI), rutting, fatigue cracking, longitudinal cracking, and transverse cracking were selected as indicators of pavement performance. Initial roughness change, long-term roughness change, and weighted distresses are used as measures of effectiveness. The logistic regression model is employed to investigate the influence of pretreatment roughness condition, pretreatment surface condition, and several other factors on the performance of PM treatments. Results from this study indicate that only thin overlay and chip seal are effective in retarding fatigue cracking. Thin overlay was also the only treatment effec...

Long-Term Cost-Effectiveness of Asphalt Pavement Pothole Patching Methods

Throw-and-roll and semipermanent patches are frequently used pothole patching techniques for asphalt pavement. To evaluate the cost-effectiveness of the two patching techniques with different combinations of materials and procedures, a 14-month survey was conducted to investigate field performance of patches installed on road sections with varying weather and traffic conditions. The performance of a patch was rated according to its overall distress conditions. With failed patches rated as 0, the service time was considered in the performance index. The multiple linear regression method was used to analyze the influence of patching methods, materials, geometric features, climatic condition, and traffic factors on the performance of patches. The field survey found that the throw-and-roll patches installed in winter deteriorated very fast, mainly because of severe freezing environment and insufficient compaction and curing. The 70% throw-and-roll patches lasted less than 14 months. Patches that survived through the first winter were typically well compacted, fully cured, and tended to last much longer. Labor costs accounted for 50% to 60% of the total cost, while material costs accounted for only 20% for cold mixes and 2% to ∼5% for semi permanent patches. Because of the reduced equipment and labor costs, the throw-and-roll patches had higher cost-effectiveness in the short term. However, the effectiveness of throw-and-roll patches decreased rapidly, and semipermanent patches exhibited higher cost-effectiveness in the long term. To improve the stability of patches, it is of great importance to apply sufficient compaction during installation.

Utilization of Construction and Demolition Wastes in Low-Volume Roads for Rural Areas in China

This paper presents a study in which the engineering properties of recycled construction and demolition wastes were evaluated for application to the construction of low-volume roads in rural areas of China. Crushed clay brick and waste concrete, two types of commonly available construction and demolition wastes, were selected. Scanning electron microscopy was used to characterize the influence of the hydration process on microstructure. Properties, including moisture–density relationships and unconfined compression strength, were evaluated. A field application of the use of construction and demolition wastes in low-volume roads was also presented. The study results indicate that construction and demolition wastes may be successfully used as a cement-stabilized base in constructing rural low-volume roads. The results of laboratory and field investigations from the study also provided reference for future mix design and pavement structural design, as well as construction quality control and quality assurance for similar applications in the future.

Investigation of Sequential Dissolution of Asphalt Binder in Common Solvents by FTIR and Binder Fractionation

AbstractAn investigation into the potential for sequential dissolution of asphalt fractions in a staged extraction scenario was conducted for common asphalt solvents. Asphalt cement subjected to six sequential washes in trichloroethylene (TCE), tetrahydrofuran (THF), toluene, or decahydronaphthalene (decalin) were evaluated using Fourier-transform infrared spectroscopy (FTIR) and fractionated for asphaltene content. The results from the FTIR were evaluated statistically using a one-way ANOVA test and the solvents induced no difference in mean carbonyl index. However, the fractionation of the asphalt cement after staged extraction showed that decalin and THF sequentially dissolved the asphalt cement while toluene remained suspect. Trichloroethylene does not appear to sequentially dissolve the asphalt cement fractions. The findings are in agreement with solubility calculations based on Hansen solubility parameters.

Investigation of Tack Coat Failure in Orthotropic Steel Bridge Deck Overlay

The failure of tack coat on orthotropic steel bridge decks is of concern because the loss of bonding ability between layers jeopardizes the deck overlay. This study investigated tack coat failure on an orthotropic steel bridge deck overlay. A field survey on overlay distress was first conducted on a regular double-layered epoxy asphalt concrete overlay to identify the major distresses. A follow-up survey was conducted by using infrared spectroscopy to detect the changes in chemical functional groups that may respond to distress. Contact analysis in a finite element platform was used to analyze the influence of the tack coat on the mechanistic characteristics of the deck overlay. Finally, shear clamps were used to evaluate the shear resistance performance of the tack coat. Comparisons of tack coat materials were made to support maintenance strategies for deck overlays.

Recommendations on Intelligent Compaction Parameters for Asphalt Resurfacing Quality Evaluation

AbstractIntelligent compaction (IC) technology provides an innovative way for continuously and instantaneously evaluating asphalt compaction quality. However, there is a lack of well-accepted stand...

Influence of Pavement Condition Data Variability on Network-Level Maintenance Decision

This study evaluated the impacts of data variability on pavement performance evaluation and maintenance planning. Three methods were used to quantify the variability of data. For pavement roughness and rut depth, the ratio of the difference between two wheelpaths over the sum value was used to quantify the data variation. For distress data, Monte Carlo simulation was used to quantify the error in distress extent, and the transition matrices were used to quantify the error in distress severity classification. An evaluation framework was proposed to investigate the influence of data variability on maintenance planning. The analysis results indicate that roughness for state routes exhibited a larger variation than that for Interstates. Pavement surface on the left wheelpath generally was smoother than that on the right path, regardless of route type. In regard to distress severity, the accuracy of distress extent at a low severity level had little influence on the overall distress index, while the accuracy of distress extent at moderate and high severity levels significantly influenced the overall distress index. The accuracy of distress severity at a moderate level had the most significant influence on the pavement distress index. For the current pavement management system used in Tennessee, the variability of roughness and distress severity level were the dominant influencing factors for maintenance planning, whereas the variability of distress extent had a slight influence on maintenance planning. There was no significant influence of variability of rut depth on maintenance planning.