Abstract
To date, the lack of experimentally validated design guidelines for the structural design of bike lane pavements has led to the adoption of pavement structures intended for low-volume roads, resulting in excessive thickness and overdesign. This approach increases both construction costs and environmental impact. Since pavements for micromobility infrastructure are subjected to significantly lower loads, they could be designed with reduced layer thicknesses and higher substitution rates of natural aggregates with recycled or reclaimed materials, leading to a more efficient and sustainable solution.
The primary objective of this study is to develop sustainable asphalt mixtures incorporating reclaimed asphalt (RAP) and recycled aggregates derived from the ceramic and steel industries. The proposed asphalt mixture is a BBTM11B-type (Thin Layer Asphalt Concrete) mix with conventional 50/70 penetration-grade bitumen, where the fine and coarse aggregates are entirely composed of these recycled materials.
For the experimental phase, four asphalt mixtures were designed: two combinations with ceramic aggregate and RAP, and two others with steel aggregate and RAP, in varying proportions. Each mixture was evaluated at five different bitumen content levels, assessing the following properties: (i) maximum and bulk density, (ii) air void content in the mix and voids in mineral aggregate (VMA), and (iii) Marshall stability and flow.
The results enabled the determination of the optimal bitumen content for each mixture, providing a robust technical basis for the design and implementation of sustainable pavements in micromobility and low-volume traffic infrastructure. This design represents an environmentally and economically viable alternative to conventional asphalt pavements for these applications.
