Abstract:
A clay slope that had looked stable began to show surface cracking and gradual movement, with distress becoming more noticeable. Field observations suggested that water infiltration might be softening the highly plastic clay and reducing its strength. An initial design proposed a stone column wall to stabilize the slopes. To optimize cost and cut-off time, the Recycled Plastic Pin has been selected as a Repair technique to stabilize 3 large-scale slopes at the Golf Club site in Dallas, Texas. Electrical Resistivity Imaging (ERI) was used to identify zones of elevated moisture and possible perched water within the slope, while Light Detection and Ranging (LiDAR) surveys provided detailed surface geometry and helped detect subtle deformation patterns. The combined data allowed us to find the likely failure zone and develop realistic stability models. Numerical analyses confirmed shallow movement within the softened clay layer under high-moisture conditions. Several layouts were studied to balance performance and constructability, and the selected configuration strengthened the upper soil mass without introducing large structural elements. After installation, the slope has remained stable through seasonal rainfall cycles. This case study demonstrates how recycled plastic pins can serve as a reliable shallow reinforcement system for high-plasticity clay slopes, offering a constructible alternative to traditional structural solutions when informed by targeted site characterization.