Investigation of the Fracture Resistance of Asphalt Mixtures at Low Temperatures with a Semi Circular Bend (SCB) Test - read free eBook in online reader or directly download on the web page. Select files or add your book in reader. Download and read online ebook Investigation of the Fracture Resistance of Asphalt Mixtures at Low Temperatures with a Semi Circular Bend (SCB) Test write by Xue Li. This book was released on 2005. Investigation of the Fracture Resistance of Asphalt Mixtures at Low Temperatures with a Semi Circular Bend (SCB) Test available in PDF, EPUB and Kindle.
Fracture Resistance Characterization of Superpave Mixtures Using the Semi-Circular Bending Test
Fracture Resistance Characterization of Superpave Mixtures Using the Semi-Circular Bending Test - read free eBook in online reader or directly download on the web page. Select files or add your book in reader. Download and read online ebook Fracture Resistance Characterization of Superpave Mixtures Using the Semi-Circular Bending Test write by Z. Wu. This book was released on 2005. Fracture Resistance Characterization of Superpave Mixtures Using the Semi-Circular Bending Test available in PDF, EPUB and Kindle. The fracture resistance of asphalt mixture is an important property directly related to pavement distresses, such as cracking. This paper reports the investigation of a newly-developed semicircular bending (SCB) test as a candidate test for the fracture resistance characterization of asphalt mixtures. Thirteen Superpave mixtures, designed with four different binder types (AC-30, PAC-40, PG70-22M, and PG76-22M) and four different compaction levels (Ndesign = 75, 97, 109, and 125), were considered in this study. The SCB tests were conducted at 25°C using a three-point bending fixture in a MTS testing system. The fracture resistance was analyzed based on an elasto-plastic fracture mechanics concept of critical strain energy release rate, also called the critical value of J-integral (Jc). Preliminary results indicate that the JC values were fairly sensitive to changes in binder type and nominal maximum aggregate size (NMAS) used in Superpave mixtures. This study suggests that the SCB test could be a valuable correlative tool in the evaluation of fracture resistance of asphalt mixtures.
Characterization of Low Temperature Crack Resistance of Crumb Rubber Modified Asphalt Mixtures Using Semi-Circular Bending Tests
Characterization of Low Temperature Crack Resistance of Crumb Rubber Modified Asphalt Mixtures Using Semi-Circular Bending Tests - read free eBook in online reader or directly download on the web page. Select files or add your book in reader. Download and read online ebook Characterization of Low Temperature Crack Resistance of Crumb Rubber Modified Asphalt Mixtures Using Semi-Circular Bending Tests write by Hainian Wang. This book was released on 2016. Characterization of Low Temperature Crack Resistance of Crumb Rubber Modified Asphalt Mixtures Using Semi-Circular Bending Tests available in PDF, EPUB and Kindle. The objective of this study was to assess the low temperature anti-cracking performance of crumb rubber modified asphalt mixtures by performing the semi-circular bending tests. The flexural tensile strength, fracture energy density, and fracture resistance were used to evaluate the rubber modified asphalt mixture's performance based on fracture mechanics J-integral concept. The semi-circular bending (SCB) tests were conducted to study the effect of crumb rubber dosage, crumb rubber size, and testing temperature on the low temperature anti-cracking performance of rubber modified asphalt mixtures. Two gradations (a dense gradation mixture and a gap-gradation mixture) were selected, and five rubber application dosages (15, 18, 20, 22, and 25 %, all by the weight of base binder) were studied in the paper. The tests were performed at temperatures of 0, -10, and -20°C. The testing results indicated that the flexural tensile strength and fracture energy density increased initially, reached to a peak point and then decreased with the increase of rubber dosage. Flexural tensile strength and fracture energy density reached its maximum value at the 20 % rubber dosage among the five rubber application dosages. The flexural tensile strength, fracture energy density, and the J-integral fracture toughness of the gap-graded rubber asphalt mixture specimens were higher than those of the dense gradation. The smaller sized particle rubber modified mixture provided a better low temperature anti-cracking performance as compared to those with bigger particle sizes. Through the comprehensive consideration of laboratory test results and field results, it was recommended that the J-integral fracture toughness should be no less than 2.8 KJ/m2 for new asphalt rubber pavement in Shannxi province.
Development of Semi-circular Bending (SCB) Fracture Test for Bituminous Mixtures
Development of Semi-circular Bending (SCB) Fracture Test for Bituminous Mixtures - read free eBook in online reader or directly download on the web page. Select files or add your book in reader. Download and read online ebook Development of Semi-circular Bending (SCB) Fracture Test for Bituminous Mixtures write by Gabriel Nsengiyumva. This book was released on 2015. Development of Semi-circular Bending (SCB) Fracture Test for Bituminous Mixtures available in PDF, EPUB and Kindle. Granted that most distresses in asphalt (flexible) concrete (AC) pavements are directly related to fracture, it becomes clear that identifying and characterizing fracture properties of AC mixtures is a critical step towards a better pavement design. This thesis examines the testing variables of a reliable and practical semicircular bending (SCB) test for evaluating the fracture characteristics of asphalt concrete mixtures at intermediate service temperature conditions. The first part of this thesis investigates the repeatability of the SCB fracture test method by integrating a statistical-experimental approach to identify testing variables of the SCB test that result in repeatable test results. Toward this end, five testing variables (the number of testing specimens, specimen thickness, notch length, loading rate, and testing temperature) of the SCB test were investigated due to their significant effects on mixture fracture characteristics. After statistical analysis of 18 specimens tested a typical testing variables, approximately, five to six specimens/replicates were found to be a reasonable sample size that could properly represent asphalt concrete fracture behavior using the SCB test method. The coefficient of variation (COV) of the mixture fracture energy was used to evaluate the effect of each variable on the repeatability of test results. A range of 1 mm/min. to 5 mm/min. for the loading rate, a notch length from 5 mm to 25 mm, and a specimen thickness of 40 mm to 60 mm and a testing temperature of 15-40°C showed the lowest variation of fracture energy. The second part of this work is to investigate the sensitivity of the SCB test using the previously determined testing variables. Fourteen different asphalt concrete (AC) mixtures collected from 12 field construction projects in Nebraska were used in this task. The ANOVA test showed statistically significant differences between mixtures at a 95% confidence level. Tukey's HSD multiple-comparison analysis found similarities within mixtures of same types and significant difference between mixtures types. In addition, the fracture energy of bituminous mixtures increased with increasing amount of virgin asphalt content in mixture. Overall, the SCB test method developed herein proved to be repeatable and sensitive to changes in mixtures, and thus a promising tool for evaluating the fatigue fracture resistance of AC mixtures.
PRO 37: 5th International RILEM Conference on Cracking in Pavements – Mitigation, Risk Assessment and Prevention
PRO 37: 5th International RILEM Conference on Cracking in Pavements – Mitigation, Risk Assessment and Prevention - read free eBook in online reader or directly download on the web page. Select files or add your book in reader. Download and read online ebook PRO 37: 5th International RILEM Conference on Cracking in Pavements – Mitigation, Risk Assessment and Prevention write by C. Petit. This book was released on 2004. PRO 37: 5th International RILEM Conference on Cracking in Pavements – Mitigation, Risk Assessment and Prevention available in PDF, EPUB and Kindle.
