An Experimental Study on the Mechanical Properties of Fine-Grained Soils Stabilized with Lime and Bamboo Geogrids Reinforcement for Subgrade Improvement
摘要
Subgrade soils in low-traffic roads, such as those on Avenida Villa Hermosa (Chiclayo, Peru), often exhibit insufficient bearing capacity, leading to premature pavement failures. While lime stabilization is commonly used, its combination with bamboo geogrids for cohesive soils has been underexplored. This study evaluates the mechanical improvement of cohesive subgrade soils through the combined use of lime and biaxial bamboo geogrids. Soil samples were stabilized with 3%, 5%, and 7% lime (by dry weight). The optimal lime-treated soil (5% lime) was then reinforced with 4-mm-thick biaxial bamboo geogrids featuring different aperture sizes (2 cm, 3 cm, and 4 cm). The bamboo fibers were chemically treated to enhance soil adhesion. Modified Proctor compaction and California bearing ratio (CBR) tests were conducted under controlled compaction to assess bearing capacity. The geogrid was placed at a depth of 3/4H from the mold’s base during CBR testing. The optimal combination—5% lime with a 4-mm-thick, 2-cm-aperture biaxial geogrid—increased the CBR value of the weakest soil by 257.58%, achieving adequate load-bearing capacity for low-volume urban roads (≤ 200 IMDA). The biaxial geogrid configuration and 2-cm spacing improved load distribution, while lime reduced swelling and increased cohesion. Lime-bamboo geogrids are a viable solution for stabilizing weak subgrades in low-to-medium traffic urban roads, particularly where traditional materials are scarce.