Search Results (5)

The rapid growth of the wind energy sector has led to a rising number of retired wind turbine blades (RWTBs) globally, posing significant environmental and logistical challenges for sustainable waste management. Handling enormous RWTBs at their end of life (EoL) has a significant negative impact on resource conservation and the environment. Conventional disposal methods, such as landfilling and incineration, raise environmental concerns due to the non-recyclable composite material used in blade manufacturing. This study explores the upcycling potential of RWTBs as innovative construction materials, addressing both waste reduction and resource efficiency in the construction industry. By exploring recent advancements in recycling techniques, this research highlights applications such as structural components, lightweight aggregates for concrete, and reinforcement elements in asphalt pavements. The key findings demonstrate that repurposing blade-derived materials not only reduces landfill dependency but also lowers carbon emissions associated with conventional construction practices. However, challenges including material compatibility, economic feasibility, and standardization require further investigation. This study concludes that upcycling wind turbine blades into construction materials offers a promising pathway toward circular economy goals. To improve technical methods and policy support for large-scale implementation, it recommends collaboration among different fields, such as those related to cementitious and asphalt materials. Full article

Abrasion resistance is a crucial factor in pavement concrete durability, influenced by compressive strength, surface finishing and curing techniques, aggregate characteristics, and testing conditions. Research shows that improving concrete’s abrasion resistance through proper mix design, additives like fibers and silica fume, and optimal curing practices can extend its service life by reducing wear from traffic and environmental forces, but concrete remains vulnerable to abrasion over time. This is a comprehensive review investigating the abrasion resistance in concrete pavements. It explores the mechanisms of abrasion resistance and standard testing methods. It then delves into the numerous factors affecting abrasion resistance, focusing on material properties (aggregates, cement type, admixtures, and water–cement ratio), pavement design (surface texture and reinforcement), and environmental conditions. Finally, the review examines advancements in enhancing abrasion resistance, including new materials and technologies, and concludes by highlighting current limitations in understanding the phenomenon and suggesting avenues for future research. This paper aims to provide a better understanding of materials, techniques, and predictive models to enhance abrasion resistance, which is crucial for enhancing the durability and longevity of concrete pavements. Full article

Pervious concrete (PC) has gained popularity as an environmentally friendly solution for mitigating the urban heat island effect and promoting sustainable construction. However, its lower compressive strength, attributed to its higher porosity required for permeability, poses challenges for withstanding heavy vehicle loads on pavements. Our study aims to improve the flexural strength of regular PC by adding advanced reinforcing materials like steel wire mesh or glass fiber mesh. This results in reinforced pervious concrete, referred to as RPC, which offers enhanced strength and durability. The primary objective of our research is to investigate the mechanical behavior of RPC, with a specific emphasis on essential design parameters such as PC elastic modulus, modulus of rupture, and stress–strain characteristics under both single and repeated loading conditions. Our findings reveal that the influence of repeated loading on the compressive strength and elastic modulus of PC pavement is negligible, as there are no significant differences observed between the two loading protocols. Notably, our statistical analysis indicates that the PC strength (fc′) averages around 15 MPa. Moreover, empirical formulas for the elastic modulus (Ec = 3072$\sqrt{f_c\prime }$) and modulus of rupture (fr = 0.86$\sqrt{f_c\prime }$) are derived from our research. Furthermore, our study establishes that the stress–strain behavior of PC closely aligns with the general concrete model proposed by a previous scholar, providing valuable insights into the material’s structural performance. These findings contribute to a better understanding of RPC’s mechanical properties and offer potential solutions for improving its suitability for heavier vehicular loads. Full article

Driven by the huge thermal energy in cement concrete pavements, thermoelectric (TE) cement has attracted considerable attention. However, the current TE cement shows poor performance, which greatly limits its application. Herein, a series of Bi_0.5Sb_1.5Te₃/carbon nanotubes (CNTs) co-reinforced cement composites have been prepared, and their TE properties were systematically investigated. It was shown that the addition of Bi_0.5Sb_1.5Te₃ particles can effectively improve the TE properties of CNTs-reinforced cement composites by building a better conductive network, increasing energy filtering and interfaces scattering. The Bi_0.5Sb_1.5Te₃/CNTs cement composites with 0.6 vol.% of Bi_0.5Sb_1.5Te₃ exhibits the highest ZT value of 1.2 × 10⁻², increased by 842 times compared to that of the CNTs-reinforced cement composites without Bi_0.5Sb_1.5Te₃. The power output of this sample with the size of 2.5 × 3.5 × 12 mm³ reaches 0.002 μW at a temperature difference of 19.1 K. These findings shed new light on the development of high-performance TE cement, which can guide continued advances in their potential application of harvesting thermal energy from pavements. Full article

The technological innovation of continuously reinforced concrete pavement (CRCP) that contains a significantly reduced amount of reinforcement and the same fundamental behavior as CRCP is called advanced reinforced concrete pavement (ARCP). This new concept of a rigid pavement structure is developed to eliminate unnecessary continuous longitudinal steel bars of CRCP by using partial length steel bars at predetermined crack locations. In Belgium, partial surface saw-cuts are used as the most effective crack induction method to eliminate the randomness in early-age crack patterns by inducing cracks at the predetermined locations of CRCP. The reinforcement layout of ARCP is designed based on the distribution of steel stress in continuous longitudinal steel bar in CRCP and the effectiveness of partial surface saw-cuts as a crack induction method. The 3D finite element (FE) model is developed to evaluate the behavior of ARCP with partial surface saw-cuts. The early-age crack characteristics in terms of crack initiation and crack propagation obtained from the FE simulation are validated with the field observations of cracking characteristics of the CRCP sections in Belgium. The finding indicates that there is fundamentally no difference in the steel stress distribution in the partial length steel bar of ARCP and continuous steel bar of CRCP. Moreover, ARCP exhibits the same cracking characteristics as CRCP even with a significantly reduced amount of continuous reinforcement. Full article