Article
Construction & Building Technology
Li Zu-yuan, Wang Hou-zhi, Shi Chen-guang, Cai Xing, Yang Jun, Yu Yun-hong
Summary: This study evaluated two fine aggregate mixtures (FAM) with different rubber particle content added to asphalt concrete as materials for the solidified trackbed. Mechanical properties of four FAM were evaluated using semicircle bending (SCB) test and CT scanning, while acoustic emission (AE) technology was used to analyze the microscopic cracking process. The results showed that the epoxy-FAM with 11% rubber content exhibited the best fracture resistance.
CONSTRUCTION AND BUILDING MATERIALS
(2022)
Article
Construction & Building Technology
Alexis Jair Enriquez-Leon, Thiago Delgado de Souza, Francisco Thiago Sacramento Aragao, Andre Maues Brabo Pereira, Liebert Parreiras Nogueira
Summary: This study proposes a criterion to select the air void content for fabricating isolated FAM testing specimens based on comprehensive examination of the AC phase using X-ray micro-computed tomography tests and digital image processing with artificial intelligence techniques. The results show that this procedure can provide key insights into the volumetric characteristics of FAM mixtures, contributing to the improvement of FAM design protocols and more accurate characterizations of their behavior.
CONSTRUCTION AND BUILDING MATERIALS
(2021)
Article
Engineering, Chemical
A. Garcia-Hernandez, L. Wan, S. Dopazo-Hilario
Summary: This paper introduces an algorithm for creating realistic virtual asphalt concretes by predicting air voids and aggregate skeleton to simulate laboratory-prepared asphalt. By considering key parameters affecting compaction and developing an equation based on the Weibull function, the algorithm's compaction requirements can be predicted.
Article
Construction & Building Technology
Zhuang Zhang, Sen Han, Hongchen Guo, Xiao Han, Chi Wu
Summary: The study found that aging time and the increase of RAP content have a negative impact on the fatigue performance of fine aggregate matrix, with aging time showing a more significant effect. Both time sweep test and strain sweep test can predict the fatigue properties of FAM, but strain sweep test is more time-saving and efficient.
CONSTRUCTION AND BUILDING MATERIALS
(2021)
Article
Construction & Building Technology
Mu-Zi Zhao, Huan Zhang, Yue Geng, Dawn E. Lehman, Yu-Yin Wang
Summary: This study aimed to investigate the compounding effect of fine recycled aggregate (FRA) replacement ratio, coarse recycled aggregate (CRA) replacement ratio, and water-to-cement ratio (w/c) on the basic creep behavior of recycled aggregate concrete (RAC). Fifteen groups of specimens were prepared and tested to measure the final basic creep value and development trend for different FRA/CRA replacement ratios and w/c. The results showed that FRA, CRA, and w/c significantly influenced the basic creep behavior of RAC. A new basic creep model considering these influences was derived and benchmarked against the test data.
CONSTRUCTION AND BUILDING MATERIALS
(2023)
Article
Construction & Building Technology
Reza Soltanabadi, Kiachehr Behfarnia
Summary: The study analyzed the behavior of deep beams containing different types of aggregates. Results showed that replacing NCA with 50% of RCA and RAP led to a reduction in shear capacity, while using 100% replacement with modified mix design achieved similar shear capacity. Deep beams containing RAP had higher absorbed energy and showed greater ductility compared to RCA, which exhibited brittleness. Additionally, the cracking patterns analysis revealed differences in flexural and diagonal cracks among the specimens.
CONSTRUCTION AND BUILDING MATERIALS
(2022)
Article
Construction & Building Technology
Dengke Wang, Gaozhan Zhang, Yang Li, Qingjun Ding
Summary: The damage of lightweight aggregate high performance concrete (LHPC) under four-point bending was experimentally investigated, and the effects of stress level and loading age on LHPC damage were elucidated. The results show that an increase in stress level aggravates the damage of LHPC but also stimulates the internal curing effect of lightweight aggregate (LWA).
CASE STUDIES IN CONSTRUCTION MATERIALS
(2023)
Article
Construction & Building Technology
Zhifei Tan, Denis Jelagin, Hassan Fadil, Zhen Leng, Rui Li, Jiwang Jiang, Peng Cao
Summary: In this study, a new virtual-specimen-based modeling approach was developed to account for aggregate contacts in asphalt concrete. The predicted complex moduli of gap-graded and dense-graded mixtures using this approach were compared with conventional image-based modeling and laboratory measurements. The virtual-specimen modeling showed that the contact region in gap-graded mixture with more large aggregates could transmit load better than in dense-graded mixture. Both modeling approaches provided good prediction accuracy, but the virtual-specimen models had more uniform and continuous stress distributions, enabling better computational convergence and nonlinear analysis of asphalt concrete.
CONSTRUCTION AND BUILDING MATERIALS
(2023)
Article
Construction & Building Technology
Wen-Chang Gao, Xin-Lei Zhang, Guang-Zhe Du, Yun-Peng Ma, Jun-Bao Fan, Yue Geng, Huan Zhang
Summary: The study aims to predict the shrinkage behavior of concrete with coal gangue aggregates. Test results showed that using coal gangue aggregates significantly increased concrete shrinkage strain, with coarse aggregates having a greater effect. A new theoretical model was developed to accurately predict the shrinkage of concrete with coal gangue aggregates.
JOURNAL OF BUILDING ENGINEERING
(2023)
Article
Construction & Building Technology
Tereza Pavlu, Kristina Fortova, Diana Mariakova, Jakub Repka, Tomas Vlach, Petr Hajek
Summary: High-performance concrete (HPC) is a cement-based material with excellent properties and durability. However, the use of high-quality natural resources and additional materials in HPC leads to high costs and environmental impact. This study explores the possibility of using recycled concrete aggregate as a substitute, and finds that while there is a slight decline in mechanical properties, the replacement does reduce autogenous shrinkage and contribute to the sustainability goals set by the United Nations.
STRUCTURAL CONCRETE
(2023)
Review
Materials Science, Multidisciplinary
Yuanxun Zheng, Yahui Zhang, Peng Zhang
Summary: The influence of recycled aggregate (RA) on the mechanical properties and durability of recycled aggregate concrete (RAC) has drawn attention due to its characteristics. Methods such as carbonation to enhance adherent mortar, weak acid treatment for old adhesion removal, addition of cementitious materials with volcanic ash effect for denser RAC, and fiber reinforcement for reduced micro cracks have been found to improve the mechanical properties of RAC. The load-bearing capacity and mechanical properties of RAC can also be significantly improved through the use of materials such as fiber reinforced polymer (FRP) for spiral constraint. Optimizing the production process not only enhances the quality of RAC, but also improves production efficiency.
JOURNAL OF MATERIALS RESEARCH AND TECHNOLOGY-JMR&T
(2021)
Article
Construction & Building Technology
Renan Carrer Nardo, Andrise Buchweitz Klug, Adalberto Leandro Faxina
Summary: The use of reclaimed asphalt pavements (RAP) is increasing due to its environmental and economic appeal. However, the use of higher percentages of RAP may result in cracking issues. This study investigates the influence of diffusion time and mixing temperature on the fatigue performance of recycled asphalt mixtures. The best fatigue performance was achieved for a diffusion time of 80 min at 135°C.
JOURNAL OF MATERIALS IN CIVIL ENGINEERING
(2023)
Article
Construction & Building Technology
Hsiao-Tsun Chien, Jia-Ruey Chang, Hui-Mi Hsu
Summary: Steel furnace slag is used as a replacement for natural aggregates in road paving, but the heavy metal components in it can overflow and form rust spots on the road's surface. This study proposes a method to detect the presence of steel furnace slag in asphalt concrete by analyzing pH value, magnetic attraction, and elemental composition.
CASE STUDIES IN CONSTRUCTION MATERIALS
(2023)
Article
Construction & Building Technology
Aya Al-Asi, Ibrahim Asi
Summary: The study demonstrated that the use of CKD in asphalt mixes can improve engineering properties without affecting the mixing procedure and time, resulting in enhanced asphalt resistance to stripping and improved fatigue life and tensile strength. In addition, CKD inclusion also led to significant improvements in diametral resilient modulus for both basalt and limestone mixes.
JOURNAL OF MATERIALS IN CIVIL ENGINEERING
(2021)
Review
Construction & Building Technology
Qin Tang, Peng Xiao, Changjiang Kou, Keke Lou, Aihong Kang, Zhengguang Wu
Summary: The research examines the impact of modified RCA on the performance improvement of HMA, including surface contact. It suggests encouraging the construction of modified aggregate roads, conducting life cycle assessments, and developing more consistent standard specifications and recommendations.
CONSTRUCTION AND BUILDING MATERIALS
(2021)
Article
Engineering, Civil
Noe Hernandez-Fernandez, John T. Harvey, Benjamin Shane Underwood, Alexandra Ossa-Lopez
Summary: This article aims to demonstrate the advanced features of two second-generation mechanistic-empirical pavement analysis engines by focusing on their ability to conduct fatigue performance analysis. The capabilities of these methodologies are demonstrated by simulating the fatigue damage performance of an example study section, showing a similar ranking in fatigue cracking performance for both software simulations. The results also highlighted significant differences in cracking initiation and progression rates for all mixture simulations before and after calibration.
TRANSPORTATION RESEARCH RECORD
(2022)
Review
Engineering, Civil
Jhony Habbouche, Ilker Boz, Benjamin Shane Underwood, Cassie Castorena, Saqib Gulzar, Andrew Fried, Jaime Preciado
Summary: This paper provides information on the current state of practice regarding the use of recycled materials and recycling agents in asphalt concrete mixtures. Not all state departments of transportation have experience with using these materials, and factors preventing their use include specification limitations, lack of expertise, and negative prior experiences. Good and frequent communication with the recycling agent supplier is crucial for successful implementation.
TRANSPORTATION RESEARCH RECORD
(2022)
Article
Engineering, Civil
Andrew Fried, Lei Gabriel Xue, Saqib Gulzar, Jaime Preciado, B. Shane Underwood, Cassie Castorena
Summary: This study evaluated the universality of the slopes proposed in NCHRP Project 09-58 for both extenders and recycling agents, and also assessed the rutting resistance of asphalt mixtures prepared using additive dosages selected to restore the high-temperature grade. The results showed different additive types yield different slopes of the blended system high-temperature grade versus additive content, and that uncertainty should be considered when establishing a dosage selection procedure. The mixtures prepared with additive dosages to restore the high-temperature grade all passed recommended Hamburg wheel-track criteria.
TRANSPORTATION RESEARCH RECORD
(2022)
Article
Engineering, Civil
Narges Matini, Saqib Gulzar, Shane Underwood, Cassie Castorena
Summary: This paper discusses the issue of pavement resilience, specifically distinguishing between functional and structural resiliency. The study uses case study simulations to demonstrate the effects of extreme weather events on structural damage and pavement performance. The findings suggest a decrease in structural performance and pavement rutting under flooding events and an increase in rutting under heatwaves.
TRANSPORTATION RESEARCH RECORD
(2022)
Article
Engineering, Civil
Boris Goenaga, B. Shane Underwood, Cassie Castorena, Paul Rogers
Summary: Recent studies have found that friction and macrotexture decrease significantly when pavements are newly overlaid, but it is unclear whether these effects are temporary and how long they last. This study quantifies these effects using sites that received surface overlays between 2019 and 2021. The results show that friction initially increases after an overlay but then decreases after reaching a maximum point. Macrotexture generally increases after overlay construction, but in some cases, the magnitude and number of peaks decay over time.
TRANSPORTATION RESEARCH RECORD
(2023)
Article
Construction & Building Technology
Saqib Gulzar, Cassie Castorena, Shane Underwood
Summary: Asphalt binders have been extensively studied for their linear viscoelastic properties and performance metrics derived for specification purposes. However, in asphalt concrete pavements, where time-dependent loads in the nonlinear regime occur, there is a need for specifications that explicitly account for the binder nonlinearity. This study characterizes the nonlinear rheological properties of asphalt binder using large amplitude oscillatory shear and evaluates the applicability of time-temperature superposition in the nonlinear regime.
INTERNATIONAL JOURNAL OF PAVEMENT ENGINEERING
(2023)
Review
Green & Sustainable Science & Technology
Saqib Gulzar, Andrew Fried, Jaime Preciado, Cassie Castorena, Shane Underwood, Jhony Habbouche, Ilker Boz
Summary: The use of reclaimed asphalt pavements (RAP) in asphalt mixtures has a long history. Recently, high RAP contents have become common, especially in the US, which significantly affects the behavior and performance of the mixtures. Recycling agents (RA) have been proposed to overcome this challenge by extending the break-even point and providing cost-effectiveness and environmental benefits. However, the scientific knowledge on the selection and use of RAs in asphalt pavements is limited, and there is a need for robust methodologies to establish threshold criteria and performance metrics.
JOURNAL OF CLEANER PRODUCTION
(2023)
Article
Engineering, Civil
Andre Kazuo Kuchiishi, Cassie Castorena, Youngsoo Richard Kim, Benjamin Shane Underwood
Summary: The small specimen dynamic modulus test is crucial for the asphalt community as it allows characterization and comparison of asphalt mixtures and serves as input for pavement performance predictions. However, acceptable limits for controlling critical experimental factors still need to be established.
TRANSPORTATION RESEARCH RECORD
(2023)
Article
Engineering, Civil
Gnana Deepika Karanam, Boris Goenaga, Benjamin Shane Underwood
Summary: This paper compares two methods, Bayesian and non-parametric, for establishing performance family curves. The Bayesian method is found to be more reliable, but the non-parametric method results in lower uncertainty when dealing with large data sets.
TRANSPORTATION RESEARCH RECORD
(2023)
Article
Engineering, Civil
Nooralhuda F. Saleh, Katie (Haslett) DeCarlo, B. Shane Underwood, William J. Pine, Gerry Huber, Nam Tran, Randy C. West, Y. Richard Kim
Summary: The validity of using quality characteristics as indicators of performance in asphalt pavement construction has been questioned, leading to increased interest in directly evaluating the performance of as-constructed materials. This paper explores the use of the Asphalt Mixture Performance Tester (AMPT) and its associated test methods to measure material properties and calculate performance indices for pay adjustments in asphalt pavement construction projects. Three different quality assurance specification frameworks were compared and evaluated for a paving project in Indiana.
TRANSPORTATION RESEARCH RECORD
(2023)
Article
Engineering, Civil
Thiago Delgado de Souza, Alexis Jair Enriquez-Leon, Marcos Lamha Rocha, Patricia Hennig Osmari, Francisco Thiago Sacramento Aragao, Andre Maues Brabo Pereira, Benjamin Shane Underwood
Summary: This paper aims to develop experimental evidence to determine the most appropriate maximum aggregate size (MAS) for fabricating fine-aggregate matrices (FAMs). Three asphalt concretes (ACs) with different MASs were tested for their stiffness and fatigue properties. X-ray micro-computed tomography (micro-CT) scanning and image analysis techniques were used to assess the AC microstructures. By combining the microstructure analysis and mechanical characteristics, the most representative MASs for fabricating isolated FAM samples were determined. The key conclusion is that ACs with nominal maximum aggregate sizes of 19.0, 12.5, and 9.5 mm are better characterized by FAMs with a MAS of 2.36 mm.
TRANSPORTATION RESEARCH RECORD
(2023)
Article
Engineering, Civil
Marcos Lamha Rocha, Francisco Thiago Sacramento Aragao, Luis Alberto Herrmann do Nascimento, Benjamin Shane Underwood
Summary: The methods for designing asphalt mixtures vary from relying on the volumetric properties to focusing on pavement performance. Advanced analysis procedures enable a comprehensive evaluation that includes predicting pavement distress based on traffic, climate, and mixture properties. A frequently used approach is the balanced mix design (BMD), which aims to achieve an optimum balance between stability and durability. This study aims to bridge the gap between volumetric properties and performance of asphalt mixtures, specifically in relation to fatigue cracking and rutting, by evaluating variations in voids and conducting performance tests to identify the optimal mixture design. Additionally, a BMD framework was developed to evaluate mixture performance in different volumetric conditions and select the optimized mixture based on predicted pavement performance and indexes for all possible combinations of component materials.
TRANSPORTATION RESEARCH RECORD
(2023)
Article
Engineering, Civil
Douglas Martins Mocelin, Mayzan Maher Isied, Maria Carolina Aparicio Alvis, Abhilash Kusam, B. Shane Underwood, Y. Richard Kim, Cassie Castorena
Summary: This study evaluates and compares two alternative approaches to consider partial availability in mixture design: availability adjusted mix design (AAMD) and corrected optimum asphalt content (COAC). The results show that both AAMD and COAC methods lead to improved cracking performance compared to the control mixtures. However, the COAC method results in increased rutting while the AAMD method remains at the same level as the control mixture in terms of rutting performance.
TRANSPORTATION RESEARCH RECORD
(2023)
Article
Engineering, Civil
Jing Ding, Jaehoon Jeong, Kangjin Caleb Lee, B. Shane Underwood, Youngsoo Richard Kim, Cassie Castorena
Summary: The standards for AMPT cyclic fatigue testing provide a way to predict asphalt mixture performance under different loading and climate conditions. To ensure the widespread implementation of this testing method, precision statements are needed. This study established an index to quantify the variation in the damage characteristic curve and conducted repeatability and reproducibility analysis. The results show that the outcomes of the analysis vary depending on the chosen point of reference for the damage characteristic curve.
TRANSPORTATION RESEARCH RECORD
(2023)
Article
Engineering, Civil
Jaime Preciado, Saqib Gulzar, Andrew Fried, Cassie Castorena, Benjamin Shane Underwood, Jhony Habbouche, Ilker Boz
Summary: Recycling agents (RAs) are added to asphalt binder blends containing recycled materials to mitigate the negative effects of adding oxidized material to asphalt mixtures. This study compared two dosage selection procedures for RAs aiming to restore high-temperature and low-temperature performance grades. Statistical analyses were applied to evaluate the rheological properties of the blends compared to benchmarked virgin binders, and it was found that both dosage selection procedures achieved rheological similarity at target-specific temperatures and binder properties.
TRANSPORTATION RESEARCH RECORD
(2023)