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Despite pressing attention on construction waste management (CWM) issues, low rates of construction waste (CW) reuse and recycling (R&R) remain a limitation in construction projects. In recent years, Building Information Modeling (BIM) has gained momentum for CWM purposes; its data-richness, visualization, and simulation capabilities provide an opportunity to enhance CW R&R planning at the project level. In this context, this study proposes temporal-based algorithms integrated with 4D-BIM for the planning of concrete and drywall waste R&R throughout construction projects. Two case studies from Central Texas were used for the demonstration of the algorithms, and estimates were validated with ground truth data and literature values from different projects in North America. The overarching objective of the proposed algorithms is to streamline estimation and visual planning of CW for on-site reuse, and off-site recycling - therefore promoting a more proactive and schedule-based CWM plan. In addition, the approach improves team communication around CWM goals of the project. Moreover, through the use of 4D-BIM, on-site waste reuse opportunities are planned in advance, thus, improving resource recovery and minimizing waste disposal in landfills., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Compatibility holds great importance because it can predict the overall performance of asphalt mixtures. Incompatible aggregate-binder duos can result in a weak and friable mix as well as increase mixtures' stripping potential. Being unaware, local agencies and contractors often struggle with premature pavement failure, which consequently places unexpected strain on the budget. Thus, this study assessed the compatibility among 18 asphalt binders with a performance grade (PG) of PG 64-22, PG 70-22, and PG 76-22, each collected from six different refineries; and eight different types of aggregates (sandstone, novaculite, limestone, and dolomite, each collected from two different quarries). Viscosity, penetration, pH, and work of cohesion values of binders were used to develop a binder ranking system. Similarly, the aggregates were ranked based on physical (specific gravity and absorption), durability (abrasion resistance and soundness), and chemical (pH and surface free energy) properties. Overall relative rankings of aggregates and binders were also provided by assigning weight factors to different tested parameters. A total of 144 aggregate-binder mixture systems were ranked based on their dry and wet work of adhesion values as well as Texas boiling test results. The compatibility ratio (CR) was also computed, and each of the systems was designated A, B, C, or D based on their relative CR values. Upon analysis, three binders (S2B2, S3B1, and S4B1) and three aggregates (DM2, LS2, and DM1) were designated as the most preferable construction materials. CR values predicted LS2, DM1, and DM2 mixtures as the most compatible mixtures. SS2, LS1, and DM2 mixtures showed the highest stripping resistance in the Texas boiling test. These databases are expected to help the agency and asphalt producers to select compatible binders and aggregates for producing durable asphalt concrete. This study covered a wide variety of aggregates and asphalt binders prevalent in but not limited to Arkansas. A database developed under this project was based on observed individual aggregates' and binders' performances as well as their combined performances. The information provided in this study will help contractors and agencies to choose the most appropriate aggregate-binder system within their reach for producing quality asphalt mixtures. By knowing the rankings, state agencies can adjust project budgets and assign timely rehabilitation due to the usage of less compatible aggregate-binder systems. Contractors can tweak the existing mix design if they must use local but inferior materials. This ranking will also help them to select project-specific materials depending on the project's significance. The refineries as well will have the opportunity to improve their products to be more compatible with local materials. [ABSTRACT FROM AUTHOR]

An experimental investigation was performed to assess the performance of a hybrid fiber-reinforced polymer/reinforced concrete bridge system. The full-scale laboratory specimen was representative of an 813 mm(32 in.) wide strip of a completed bridge in San Patricio County, Tex. The specimen was first subjected to static loading prior to casting the reinforced concrete deck. Displacement, strain, and acoustic emission were recorded. After completion of the nondestructive static loading a reinforced concrete deck was cast in the laboratory to represent one unit of the completed bridge. Load was statically applied with several increased load cycles until failure occurred at a load level exceeding 18 times the calculated design load. The results of the static testing indicated that the original design of the hybrid bridge was very conservative. An optimized design of the hybrid bridge was then derived. The static load testing program and the resulting optimized design are described. [ABSTRACT FROM AUTHOR]