Potential Application of Natural Fibres for the Reinforcement of Unpaved Forest Roads—Response after RL-CBR Tests
Source abstract
Abstract
Unpaved roads are essential as transportation infrastructure. These roads are traditionally built utilizing local soils and aggregates. The application of different materials to improve the strength and the overall performance of these road solutions has been investigated. This study focuses on the assessment of the suitability of reinforcing a fine soil using natural fibres from the forest value chain—specifically, pine needles—for unpaved forest roads. The resilient response of both unreinforced and reinforced soils was assessed with RL-CBR tests (California Bearing tests with repeated load) for different percentages of natural fibres incorporated into the soil. The force–penetration response, CBR value, recoverable and permanent displacements, and equivalent modulus were estimated. The effect of different load stages on the elastic response of both unreinforced and reinforced soils was also evaluated. The CBR values improved with the addition of pine needles; the best response was observed for specimens reinforced with 1% (mass) of these natural fibres (the CBR value increased by 45%). The equivalent modulus also was improved, showing that the stiffness of the soil increased with the inclusion of reinforcement. The findings imply that RL-CBR studies offer a promising method for obtaining important design parameters, especially for unpaved forest roads where investments in soil characterization are frequently limited.
Source: crossref · Quality: baseline
Research context
OpenAlex topics: Geotechnical Engineering and Soil Stabilization · Natural Fiber Reinforced Composites · Structural Behavior of Reinforced Concrete
SciVX discovery tags are terminology-based. OpenAlex topics are source-provided classifications.
Affiliations
RISCO—Research Center for Risks and Sustainability in Construction, Department of Civil Engineering, University of Aveiro, 3810-193 Aveiro, Portugal
Funding
project TRANSFORM · Portuguese Resilience Plan (PRR) · European Union—NextGenerationEU · FCT (“Fundação para a Ciência e a Tecnologia”-Portugal)
References (24)
Show source-provided references
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