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This article studies the practical road performance of recycled materials from construction waste, relying on the paving test section of the supporting project for the Qingdao Cross-Sea Bridge. The research focuses on the construction technology and road performance of using recycled construction waste materials in urban road sub-base construction. Through indoor tests such as sieving and unconfined compressive strength tests, relevant technical indicators were obtained and analyzed. Additionally, periodic core sampling, compaction tests, and rebound deflection tests were conducted on-site according to relevant standards to thoroughly investigate the specific effects of using construction waste in practice and to analyze and evaluate the actual feasibility of the materials for road use. The results indicate that the particle gradation of the construction mix in the test section aligns well with the target gradation, and the dosage of the mixing agent meets the design requirements. The 7-day unconfined compressive strength already satisfied the technical requirements for heavy and extremely heavy traffic on highways as specified in the "Technical Specifications for Construction of Highway Pavement Subbase" (JTG/T F20-2015), with the 14-day strength generally reaching 7 MPa. Core sampling revealed good aggregate gradation, smooth and straight profiles, and the thickness and strength of all parts meet the specifications. The compaction levels met the testing requirements, the surface deflection values showed a decreasing trend, and the deformation resistance was good, consistent with the general development patterns of semi-rigid sub-bases. [ABSTRACT FROM AUTHOR]

At present, construction waste recycled aggregates only partially replace natural aggregates to prepare road-based materials. This study addressed this limitation and experimentally investigated the mechanical properties of cement-stabilized macadam base materials utilizing a construction waste recycled aggregate. The feasibility of using these raw materials to prepare cement-stabilized macadam bases was established via experimental validation. Subsequently, compaction tests were conducted to ascertain the maximum dry density and optimum moisture content in the mixture. The mechanical characteristics were further examined using unconfined compressive strength tests, analyzing and discussing the influences of varying cement dosages and curing periods on the material strength. The results indicate that the properties of the recycled aggregates satisfied specification requirements, demonstrating satisfactory mechanical properties. The unconfined compressive strength with a 7-day curing period and a 5% cement content fulfilled the technical standards for expressway-grade heavy and extremely heavy traffic, while that with a 6% cement content (with an added curing agent) met these requirements after just 1 day. Additionally, the curing agent enhanced the early strength of the recycled aggregate base material. This study has broken through the technical bottleneck of low content of recycled aggregate, achieved 100% replacement of natural aggregate, and promoted the sustainable development of the industry. [ABSTRACT FROM AUTHOR]

Membership change has been found to stimulate collective idea generation but to not always benefit group creativity—the generation of final outcomes that are novel and useful. Based on motivated information processing theory, we propose that membership change challenges group members to generate more ideas, but that this only contributes to group creativity when members have high levels of prosocial motivation and are willing to process and integrate each other's ideas. In a laboratory study of 56 student groups, we found that incremental, but not radical, idea generation mediated the positive effect of membership change on group creativity, and only when group members were prosocially motivated. The present study points to different roles of incremental versus radical ideas and underscores the importance of accounting for prosocial motivation in groups for reaping the benefits of membership change in relation to group creativity. [ABSTRACT FROM AUTHOR]

One of the most fundamental questions in team creativity research is the relationship between individual member creativity and team creativity. The two answers that team creativity research has advanced–teams are more creative when their average member creativity is higher (the additive model) and teams are more creative when their most creative member is more creative (the disjunctive model) are straightforward. Surprising, however, is that neither the additive model nor the disjunctive model is consistently supported, begging the question of what moderates the predictive power of these models. We address this question by integrating individual-to-team creativity models with team process research. We propose that team information elaboration is a key moderating variable, such that average member creativity is more positively related to team creativity with higher information elaboration, and the highest member creativity is more positively related to team creativity with lower information elaboration. A multi-source study of 60 sales teams (483 employees) in a Chinese bakery chain supported these hypotheses. In addition, the study did not support the prediction that the most creative member's outgoing advice ties (as a conduit for the dissemination of ideas) would further moderate the joint effect of the highest individual creativity and team information elaboration on team creativity. [ABSTRACT FROM AUTHOR]

The successful development of tight oil reservoirs in the U.S. shows the bright future of unconventional reservoirs. Tight oil reservoirs will be the main target of exploration and development in the future, and CO2 huff-n-puff is one of the most important methods to enhance oil recovery factor of tight oil reservoirs in North America. To improve the performance of CO2 huff-n-puff, injection and production parameters need to be optimized through numerical simulation. The phase behavior and microscopic flow mechanism of CO2 huff-n-puff in porous media need to be further investigated. This paper presents a detailed review of phase behavior and microscopic flow mechanism in tight porous media by CO2 huff-n-puff. Phase behavior in tight porous media is different from that in a PVT cylinder since the capillary pressure in tight porous media reduces the bubble point pressure and increases the miscibility pressure and critical temperature. The condensate pressure in tight porous media and nonequilibrium phase behavior need to be further investigated. The microscopic flow mechanism during CO2 huff-n-puff in tight porous media is complicated, and the impact of molecular diffusion, gas-liquid interaction, and fluid-rock interaction on multiphase flow is significant especially in tight porous media. Nuclear magnetic resonance (NMR) and molecular simulation are efficient methods to describe the microscopic flow in tight oil reservoirs, while the NMR is not cost-effective and molecular simulation needs to be improved to better characterize and model the feature of porous media. The improved molecular simulation is still a feasible method to understand the microscopic flow mechanism of CO2 huff-n-puff in tight oil reservoirs in the near future. The microscopic flow model in micropore network based on digital core is worth to be established, and phase behavior needs to be further incorporated into the microscopic flow model of CO2 huff-n-puff in tight porous media. [ABSTRACT FROM AUTHOR]