What are the friction coefficients of granite surfaces for outdoor trash can lids?

The friction coefficient of granite surfaces for outdoor trash can lids typically ranges from 0.4 to 0.6 under dry conditions, though this can vary significantly based on surface finish, environmental factors, and contact materials. Granite's natural roughness provides decent resistance against sliding, making it suitable for heavy lids that need to stay in place while allowing access. However, when wet, the coefficient can drop to 0.3-0.4, increasing slip risk. Factors like surface polishing, dirt accumulation, and ice formation further impact performance. For optimal safety and functionality, lid designs should account for these variations, possibly incorporating textured finishes or complementary materials to maintain adequate friction in all weather conditions. Regular maintenance to keep surfaces clean and free of debris is also crucial for consistent friction performance.